@article{chen_travanty_garshong_crossley_wasserberg_apperson_roe_ponnusamy_2023, title={Detection of Orientia spp. Bacteria in Field-Collected Free-Living Eutrombicula Chigger Mites, United States}, volume={29}, ISSN={["1080-6059"]}, DOI={10.3201/eid2908.230528}, abstractNote={Scrub typhus, a rickettsial disease caused by Orientia spp., is transmitted by infected larval trombiculid mites (chiggers). We report the molecular detection of Orientia species in free-living Eutrombicula chiggers collected in an area in North Carolina, USA, to which spotted fever group rickettsiae infections are endemic.}, number={8}, journal={EMERGING INFECTIOUS DISEASES}, author={Chen, Kaiying and Travanty, Nicholas V. and Garshong, Reuben and Crossley, Dac and Wasserberg, Gideon and Apperson, Charles S. and Roe, R. Michael and Ponnusamy, Loganathan}, year={2023}, month={Aug}, pages={1676–1679} } @article{luan_mccord_west_cave_travanty_apperson_roe_2023, title={Mosquito Blood Feeding Prevention Using an Extra-Low DC Voltage Charged Cloth}, volume={14}, ISSN={["2075-4450"]}, url={https://doi.org/10.3390/insects14050405}, DOI={10.3390/insects14050405}, abstractNote={Mosquito vector-borne diseases such as malaria and dengue pose a major threat to human health. Personal protection from mosquito blood feeding is mostly by treating clothing with insecticides and the use of repellents on clothing and skin. Here, we developed a low-voltage, mosquito-resistant cloth (MRC) that blocked all blood feeding across the textile and was flexible and breathable. The design was based on mosquito head and proboscis morphometrics, the development of a novel 3-D textile with the outer conductive layers insulated from each other with an inner, non-conductive woven mesh, and the use of a DC (direct current; extra-low-voltage) resistor-capacitor. Blockage of blood feeding was measured using host-seeking Aedes aegypti adult female mosquitoes and whether they could blood feed across the MRC and an artificial membrane. Mosquito blood feeding decreased as voltage increased from 0 to 15 volts. Blood feeding inhibition was 97.8% at 10 volts and 100% inhibition at 15 volts, demonstrating proof of concept. Current flow is minimal since conductance only occurs when the mosquito proboscis simultaneously touches the outside layers of the MRC and is then quickly repelled. Our results demonstrated for the first time the use of a biomimetic, mosquito-repelling technology to prevent blood feeding using extra-low energy consumption.}, number={5}, journal={INSECTS}, author={Luan, Kun and McCord, Marian G. and West, Andre J. and Cave, Grayson and Travanty, Nicholas V. and Apperson, Charles S. and Roe, R. Michael}, year={2023}, month={Apr} } @article{johnson_ponnusamy_richards_apperson_2022, title={Analyses of Bloodmeal Hosts and Prevalence of Rickettsia parkeri in the Gulf Coast Tick Amblyomma maculatum (Acari: Ixodidae) From a Reconstructed Piedmont Prairie Ecosystem, North Carolina}, volume={4}, ISSN={["1938-2928"]}, url={https://doi.org/10.1093/jme/tjac033}, DOI={10.1093/jme/tjac033}, abstractNote={Abstract}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Johnson, Connie R. and Ponnusamy, Loganathan and Richards, Allen L. and Apperson, Charles S.}, editor={Macaluso, KevinEditor}, year={2022}, month={Apr} } @article{travanty_vargo_schal_apperson_ponnusamy_2022, title={Bacterial Isolates Derived from Nest Soil Affect the Attraction and Digging Behavior of Workers of the Red Imported Fire Ant, Solenopsis invicta Buren}, volume={13}, ISSN={["2075-4450"]}, url={https://doi.org/10.3390/insects13050444}, DOI={10.3390/insects13050444}, abstractNote={Populations of monogyne and polygyne red imported fire ants (RIFA), Solenopsis invicta Buren, are distributed throughout the southern United States. This ant species is hazardous to farm animals and workers, damages infrastructure, and depletes native arthropod populations. Colony expansion is affected by several biotic factors, but the effects of soil microbes on ant behavior related to soil excavation within nest sites have not been investigated. Consequently, we cultured bacteria from RIFA nest soils. The effects of individual bacterial isolates and bacterial cell densities on the choice of digging site as well as digging activity of monogyne and polygyne RIFA worker ants were evaluated in two-choice bioassays. Based on phylogenetic analysis, 17 isolates were selected and tested initially at 5 × 108 cells/mL and 20 workers per assay. Firmicutes (Bacillus, Paenibacillus, Brevibacillus) repelled the ants, but Arthrobacter woluwensis strongly attracted ants. Subsequently, the six isolates having the greatest positive or negative effects on ant behavior were evaluated at a lower bacterial cell and worker ant densities. Ant responses to these bacteria generally decreased as cell densities declined to 5 × 106 cells/mL. Observations of ant behavior during a three-hour, two-choice bioassay revealed that ants generally visited both control and bacteria-treated sand prior to making a digging site choice. Our research results indicate that soil bacteria may mediate ant nest expansion or relocation and foraging tunnel construction. Identification of bacterial metabolites that affect RIFA digging behavior merits additional research because these compounds may provide a basis for novel management strategies that repel RIFA away from sensitive infrastructure or attract fire ants to insecticidal baits.}, number={5}, journal={INSECTS}, publisher={MDPI AG}, author={Travanty, Nicholas V and Vargo, Edward L. and Schal, Coby and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2022}, month={May} } @article{ponnusamy_garshong_mclean_wasserberg_durden_crossley_apperson_roe_2022, title={Rickettsia felis and Other Rickettsia Species in Chigger Mites Collected from Wild Rodents in North Carolina, USA}, volume={10}, ISSN={["2076-2607"]}, url={https://www.mdpi.com/2076-2607/10/7/1342}, DOI={10.3390/microorganisms10071342}, abstractNote={Chiggers are vectors of rickettsial pathogenic bacteria, Orientia spp., that cause the human disease, scrub typhus, in the Asian–Pacific area and northern Australia (known as the Tsutsugamushi Triangle). More recently, reports of scrub typhus in Africa, southern Chile, and the Middle East have reshaped our understanding of the epidemiology of this disease, indicating it has a broad geographical distribution. Despite the growing number of studies and discoveries of chigger-borne human disease outside of the Tsutsugamushi Triangle, rickettsial pathogens in chigger mites in the US are still undetermined. The aim of our study was to investigate possible Rickettsia DNA in chiggers collected from rodents in North Carolina, USA. Of 46 chiggers tested, 47.8% tested positive for amplicons of the 23S-5S gene, 36.9% tested positive for 17 kDa, and 15.2% tested positive for gltA. Nucleotide sequence analyses of the Rickettsia-specific 23S-5S intergenic spacer (IGS), 17 kDa, and gltA gene fragments indicated that the amplicons from these chiggers were closely related to those in R. felis, R. conorii, R. typhi, and unidentified Rickettsia species. In this study, we provide the first evidence of Rickettsia infection in chiggers collected from rodents within the continental USA. In North Carolina, a US state with the highest annual cases of spotted fever rickettsioses, these results suggest chigger bites could pose a risk to public health, warranting further study.}, number={7}, journal={MICROORGANISMS}, author={Ponnusamy, Loganathan and Garshong, Reuben and McLean, Bryan S. and Wasserberg, Gideon and Durden, Lance A. and Crossley, Dac and Apperson, Charles S. and Roe, R. Michael}, year={2022}, month={Jul} } @article{travanty_vargo_apperson_ponnusamy_2021, title={Colonization by the Red Imported Fire Ant, Solenopsis invicta, Modifies Soil Bacterial Communities}, volume={8}, ISSN={["1432-184X"]}, url={https://doi.org/10.1007/s00248-021-01826-4}, DOI={10.1007/s00248-021-01826-4}, abstractNote={The long-standing association between insects and microorganisms has been especially crucial to the evolutionary and ecological success of social insect groups. Notably, research on the interaction of the two social forms (monogyne and polygyne) of the red imported fire ant (RIFA), Solenopsis invicta Buren, with microbes in its soil habitat is presently limited. In this study, we characterized bacterial microbiomes associated with RIFA nest soils and native (RIFA-negative) soils to better understand the effects of colonization of RIFA on soil microbial communities. Bacterial community fingerprints of 16S rRNA amplicons using denaturing gradient gel electrophoresis revealed significant differences in the structure of the bacterial communities between RIFA-positive and RIFA-negative soils at 0 and 10 cm depths. Illumina sequencing of 16S rRNA amplicons provided fine-scale analysis to test for effects of RIFA colonization, RIFA social form, and soil depth on the composition of the bacterial microbiomes of the soil and RIFA workers. Our results showed the bacterial community structure of RIFA-colonized soils to be significantly different from native soil communities and to evidence elevated abundances of several taxa, including Actinobacteria. Colony social form was not found to be a significant factor in nest or RIFA worker microbiome compositions. RIFA workers and nest soils were determined to have markedly different bacterial communities, with RIFA worker microbiomes being characterized by high abundances of a Bartonella-like endosymbiont and Entomoplasmataceae. Cloning and sequencing of the 16S rRNA gene revealed the Bartonella sp. to be a novel bacterium.}, journal={MICROBIAL ECOLOGY}, publisher={Springer Science and Business Media LLC}, author={Travanty, Nicholas V. and Vargo, Edward L. and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2021}, month={Aug} } @article{luan_west_mccord_denhartog_shi_bettermann_li_travanty_mitchell_cave_et al._2021, title={Mosquito-Textile Physics: A Mathematical Roadmap to Insecticide-Free, Bite-Proof Clothing for Everyday Life}, volume={12}, ISSN={2075-4450}, url={http://dx.doi.org/10.3390/insects12070636}, DOI={10.3390/insects12070636}, abstractNote={Garments treated with chemical insecticides are commonly used to prevent mosquito bites. Resistance to insecticides, however, is threatening the efficacy of this technology, and people are increasingly concerned about the potential health impacts of wearing insecticide-treated clothing. Here, we report a mathematical model for fabric barriers that resist bites from Aedes aegypti mosquitoes based on textile physical structure and no insecticides. The model was derived from mosquito morphometrics and analysis of mosquito biting behavior. Woven filter fabrics, precision polypropylene plates, and knitted fabrics were used for model validation. Then, based on the model predictions, prototype knitted textiles and garments were developed that prevented mosquito biting, and comfort testing showed the garments to possess superior thermophysiological properties. Our fabrics provided a three-times greater bite resistance than the insecticide-treated cloth. Our predictive model can be used to develop additional textiles in the future for garments that are highly bite resistant to mosquitoes.}, number={7}, journal={Insects}, publisher={MDPI AG}, author={Luan, Kun and West, Andre J. and McCord, Marian G. and DenHartog, Emiel A. and Shi, Quan and Bettermann, Isa and Li, Jiayin and Travanty, Nicholas V. and Mitchell, Robert D., III and Cave, Grayson L. and et al.}, year={2021}, month={Jul}, pages={636} } @article{deguenon_riegel_cloherty-duvernay_chen_stewart_wang_gittins_tihomirov_apperson_mccord_et al._2021, title={New Mosquitocide Derived From Volcanic Rock}, volume={58}, ISSN={["1938-2928"]}, DOI={10.1093/jme/tjaa141}, abstractNote={Abstract}, number={1}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Deguenon, Jean M. and Riegel, Claudia and Cloherty-Duvernay, Erin R. and Chen, Kaiying and Stewart, David A. and Wang, Bo and Gittins, David and Tihomirov, Larissa and Apperson, Charles S. and McCord, Marian G. and et al.}, year={2021}, month={Jan}, pages={458–464} } @article{kakumanu_marayati_schal_apperson_wasserberg_ponnusamy_2021, title={Oviposition-Site Selection of Phlebotomus papatasi (Diptera: Psychodidae) Sand Flies: Attraction to Bacterial Isolates From an Attractive Rearing Medium}, volume={58}, ISSN={["1938-2928"]}, url={https://doi.org/10.1093/jme/tjaa198}, DOI={10.1093/jme/tjaa198}, abstractNote={Abstract}, number={2}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, publisher={Oxford University Press (OUP)}, author={Kakumanu, Madhavi L. and Marayati, Bahjat F. and Schal, Coby and Apperson, Charles S. and Wasserberg, Gideon and Ponnusamy, Loganathan}, editor={Johnson, RichardEditor}, year={2021}, month={Mar}, pages={518–527} } @article{kakumanu_marayati_wada-katsumata_wasserberg_schal_apperson_ponnusamy_2021, title={Sphingobacterium phlebotomi sp. nov., a new member of family Sphingobacteriaceae isolated from sand fly rearing substrate}, volume={71}, ISSN={["1466-5034"]}, url={https://doi.org/10.1099/ijsem.0.004809}, DOI={10.1099/ijsem.0.004809}, abstractNote={A Gram-stain-negative, rod-shaped, non-motile, non-spore-forming, aerobic bacterium, designated type strain SSI9T, was isolated from sand fly (Phlebotomus papatasi Scopoli; Diptera: Psychodidae) rearing substrate and subjected to polyphasic taxonomic analysis. Strain SSI9T contained phosphatidylethanolamine as a major polar lipid, MK-7 as the predominant quinone, and C16 : 1ω6c/C16 : 1ω7c, iso-C15 : 0, iso-C17 : 0 3-OH and C16 : 0 as the major cellular fatty acids. Phylogenetic analysis based on 16S rRNA gene sequences revealed that SSI9T represents a member of the genus Sphingobacterium , of the family Sphingobacteriaceae sharing 96.5–88.0 % sequence similarity with other species of the genus Sphingobacterium . The results of multilocus sequence analysis using the concatenated sequences of the housekeeping genes recA, rplC and groL indicated that SSI9T formed a separate branch in the genus Sphingobacterium . The genome of SSI9T is 5 197 142 bp with a DNA G+C content of 41.8 mol% and encodes 4395 predicted coding sequences, 49 tRNAs, and three complete rRNAs and two partial rRNAs. SSI9T could be distinguished from other species of the genus Sphingobacterium with validly published names by several phenotypic, chemotaxonomic and genomic characteristics. On the basis of the results of this polyphasic taxonomic analysis, the bacterial isolate represents a novel species within the genus Sphingobacterium , for which the name Sphingobacterium phlebotomi sp. nov. is proposed. The type strain is SSI9T (=ATCC TSD-210T=LMG 31664T=NRRL B-65603T).}, number={5}, journal={INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY}, author={Kakumanu, Madhavi L. and Marayati, Bahjat Fadi and Wada-Katsumata, Ayako and Wasserberg, Gideon and Schal, Coby and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2021} } @article{ponnusamy_sutton_mitchell_sonenshine_apperson_roe_2021, title={Tick Ecdysteroid Hormone, Global Microbiota/Rickettsia Signaling in the Ovary versus Carcass during Vitellogenesis in Part-Fed (Virgin) American Dog Ticks, Dermacentor variabilis}, volume={9}, ISSN={["2076-2607"]}, url={https://www.mdpi.com/2076-2607/9/6/1242}, DOI={10.3390/microorganisms9061242}, abstractNote={The transovarial transmission of tick-borne bacterial pathogens is an important mechanism for their maintenance in natural populations and transmission, causing disease in humans and animals. The mechanism for this transmission and the possible role of tick hormones facilitating this process have never been studied. Injections of physiological levels of the tick hormone, 20-hydroxyecdysone (20E), into part-fed (virgin) adult females of the American dog tick, Dermacentor variabilis, attached to the host caused a reduction in density of Rickettsia montanensis in the carcass and an increase in the ovaries compared to buffer-injected controls. This injection initiates yolk protein synthesis and uptake by the eggs but has no effect on blood feeding. Francisella sp. and R. montanensis were the predominant bacteria based on the proportionality in the carcass and ovary. The total bacteria load increased in the carcass and ovaries, and bacteria in the genus Pseudomonas increased in the carcass after the 20E injection. The mechanism of how the Rickettsia species respond to changes in tick hormonal regulation needs further investigation. Multiple possible mechanisms for the proliferation of R. montanensis in the ovaries are proposed.}, number={6}, journal={MICROORGANISMS}, author={Ponnusamy, Loganathan and Sutton, Haley and Mitchell, Robert D. and Sonenshine, Daniel E. and Apperson, Charles S. and Roe, Richard Michael}, year={2021}, month={Jun} } @article{mitchell_lin_vaughn_apperson_meshnick_commins_2020, title={Association between lone star tick bites and increased alpha-gal sensitization: evidence from a prospective cohort of outdoor workers}, volume={13}, ISSN={["1756-3305"]}, DOI={10.1186/s13071-020-04343-4}, abstractNote={Abstract}, number={1}, journal={PARASITES & VECTORS}, author={Mitchell, Cedar L. and Lin, Feng-Chang and Vaughn, Meagan and Apperson, Charles S. and Meshnick, Steven R. and Commins, Scott P.}, year={2020}, month={Sep} } @article{travanty_apperson_ponnusamy_2019, title={A Diverse Microbial Community Supports Larval Development and Survivorship of the Asian Tiger Mosquito (Diptera: Culicidae)}, volume={56}, ISSN={["1938-2928"]}, url={https://doi.org/10.1093/jme/tjz003}, DOI={10.1093/jme/tjz003}, abstractNote={Abstract Laboratory microcosm experiments were conducted to evaluate effects of bacteria isolated from senescent white oak leaves on the growth and survivorship of larval Aedes albopictus (Skuse). Larvae hatched from surface-sterilized eggs were reared in microcosms containing individual bacterial isolates, combined isolates (Porphyrobacter sp., Enterobacter asburiae, Acidiphilium rubrum, Pseudomonas syringae, and Azorhizobium caulinodans), a positive control containing a microbial community from an infusion of white oak leaves, and a negative control consisting of sterile culture media. Experiments were conducted for 21 d after which microcosms were deconstructed, larval survivorship was calculated, and bacteria contained in pupae, and adults that developed were quantified to determine rates of transstadial transmission. Positive control microcosms containing diverse microbial communities had an average (±SE) pupation rate of 89.3 (±5.8)% and average larval survivorship of 96.0 (± 2.3)%. Pupation in microcosms with bacterial isolates only occurred twice among all experimental replications; average larval survivorship ranged from 19 to 56%, depending on treatment. Larval growth was not found to be dependent on bacterial isolate density or isolate species, and larval survivorship was dependent on bacterial isolate density, not on isolate species. Potential mechanisms for failed development of larvae in microcosms with bacterial isolates are discussed. Bacterial isolates alone did not support larval development. High larval survivorship in positive control microcosms suggests that a diverse microbial community is required to complete larval development. Additional studies are needed to evaluate larval growth and survivorship on nonbacterial microbes, such as fungi and protozoa.}, number={3}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, publisher={Oxford University Press (OUP)}, author={Travanty, Nicholas V. and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2019}, month={May}, pages={632–640} } @article{shymanovich_faw_hajhashemi_teague_schal_ponnusamy_apperson_hatano_wasserberg_2019, title={Diel periodicity and visual cues guide oviposition behavior in Phlebotomus papatasi, vector of old-world cutaneous leishmaniasis}, volume={13}, ISSN={1935-2735}, url={http://dx.doi.org/10.1371/journal.pntd.0007165}, DOI={10.1371/journal.pntd.0007165}, abstractNote={Background Phlebotomine sand flies are vectors of human leishmaniases, important neglected tropical diseases. In this study, we investigated diel patterns of oviposition behavior, effects of visual cues on oviposition-site selection, and whether these affect the attraction of gravid Phlebotomus papatasi (Scopoli), the vector of old-world cutaneous leishmaniasis, to olfactory cues from oviposition sites. Methodology/principal findings To evaluate these questions, we conducted a series of experiments using attraction and oviposition assays within free-flight test chambers containing gravid females entrained under a 14:10 hrs light:dark photoperiod. By replacing sticky-screens or moist filter papers every three hours, we showed that oviposition site search occurs mainly in the latest part of the night whereas peak oviposition occurs during the early part of the night. Behavioral responses to olfactory oviposition cues are regulated by time-of-day and can be disrupted by transient exposure to a constant darkness photoperiod. Gravid females, but not any other stage, age, or sex, were attracted to dark, round oviposition jars, possibly resembling rodent burrow openings. This visual attraction disappeared in the absence of an illumination source. Egg deposition rate was not affected by jar color. Olfactory cues had the strongest effect when the visual cues were minimal. Conclusion and significance Our study showed, for the first time, that visual cues in the form of oviposition-site color, lighting level, and photoperiod are important in guiding the oviposition behavior of phlebotomine sand flies. Furthermore, such visual cues could modify the flies’ sensitivity to olfactory oviposition cues. Our results suggest that chemosensory and visual cues are complementary, with visual cues used to orient gravid females towards oviposition sites, possibly at long- to medium-ranges during crepuscular periods, while olfactory cues are used to approach the burrow in darkness and assess its suitability at close-range. Implications to sand fly control are discussed.}, number={3}, journal={PLOS Neglected Tropical Diseases}, publisher={Public Library of Science (PLoS)}, author={Shymanovich, Tatsiana and Faw, Lindsey and Hajhashemi, Nima and Teague, Jimmie and Schal, Coby and Ponnusamy, Loganathan and Apperson, Charles S. and Hatano, Eduardo and Wasserberg, Gideon}, editor={Oliveira, FabianoEditor}, year={2019}, month={Mar}, pages={e0007165} } @article{travanty_ponnusamy_kakumanu_nicholson_apperson_2019, title={Diversity and structure of the bacterial microbiome of the American dog tick, Dermacentor variabilis, is dominated by the endosymbiont Francisella}, volume={79}, ISSN={["1878-7665"]}, url={https://doi.org/10.1007/s13199-019-00642-2}, DOI={10.1007/s13199-019-00642-2}, number={3}, journal={SYMBIOSIS}, publisher={Springer Science and Business Media LLC}, author={Travanty, Nicholas V. and Ponnusamy, Loganathan and Kakumanu, Madhavi L. and Nicholson, William L. and Apperson, Charles S.}, year={2019}, month={Nov}, pages={239–250} } @article{halbkat_luan_cave_mccord_roe_denhartog_travanty_apperson_west_2019, title={Fabric infused with a botanical repellent for protection against mosquitoes}, volume={110}, ISSN={0040-5000 1754-2340}, url={http://dx.doi.org/10.1080/00405000.2019.1603576}, DOI={10.1080/00405000.2019.1603576}, abstractNote={Abstract Mosquito resistant apparel has become increasingly sought-after due to the rise in vector-borne illnesses such as the Zika Virus, Malaria, and Dengue Fever. Botanical insect repellents have been introduced to the market for consumers that desire a natural solution involving no pesticides or added chemicals. Fabric swatches consisting of 80% nylon and 20% elastane were separately treated with an organic repellent using a patented nonwoven vessel. The fabrics were then tested for effectiveness in repelling the mosquito Aedes aegypti using an arm-in-cage assay, the most commonly used method for mosquito repellents. The repellents were also evaluated and rated by study participants according to their preference for the appeal of the scent. The treatment method is user-friendly, enabling consumers to treat their clothing with an organic insect repellent as opposed to applying a synthetic chemical to their clothing and skin. The infused fabrics showed to be effective at repelling mosquitoes for up to 8 h after repellent infusion.}, number={10}, journal={The Journal of The Textile Institute}, publisher={Informa UK Limited}, author={Halbkat, Lilah and Luan, Kun and Cave, Grayson and McCord, Marian and Roe, Michael and DenHartog, Emiel and Travanty, Nicholas J. and Apperson, Charles S. and West, Andre J.}, year={2019}, month={Apr}, pages={1468–1474} } @article{ponnusamy_willcox_roe_davidson_linsuwanon_schuster_richards_meshnick_apperson_2018, title={Bacterial microbiome of the chigger mite Leptotrombidium imphalum varies by life stage and infection with the scrub typhus pathogen Orientia tsutsugamushi}, volume={13}, ISSN={["1932-6203"]}, url={https://doi.org/10.1371/journal.pone.0208327}, DOI={10.1371/journal.pone.0208327}, abstractNote={Scrub typhus is a mites-borne rickettsiosis caused by the obligate intracellular Gram-negative bacterium Orientia tsutsugamushi. The disease is potentially life threatening and is prevalent in tropical Asia, islands of the western Pacific Ocean and northern Australia where an estimated one million cases occur annually. Orientia tsutsugamushi is transmitted by the bite of larval mites in the genus Leptotrombidium. In the present study, the composition of the microbiome in larvae, deutonymphs and adult males and females from laboratory colonies of L. imphalum that were infected as well as uninfected with O. tsutsugamushi were investigated by high-throughput sequencing of the bacterial 16S rRNA gene. Notably, the bacterial microbiomes of infected adult females were dominated by sequences of O. tsutsugamushi and an unidentified species of Amoebophilaceae, which together comprised 98.2% of bacterial sequences. To improve the taxonomic resolution of the Amoebophilaceae OTU a nearly full length sequence of the 16S rRNA gene was amplified, cloned, and Sanger sequenced. Infected female mites had 89 to 92% nucleotide identity with the Amoebophilaceae family, indicating that the bacterium was likely to be a species of a novel genus. The species composition of bacterial communities varied between mite life stages regardless of their infection status. Uninfected adults exhibited greater species diversity than adults infected with O. tsutsugamushi. In the infected colony, the rate of filial infection with Orientia was less than 100%. Larval and male mites that were PCR-negative for Orientia contained low numbers of sequences of Amoebophilaceae (0.01 and 0.06%, respectively) in their taxonomic profiles, suggesting that a mutualistic relationship exists between the novel species of Amoebophilaceae and O. tsutsugamushi. Our study findings provide the basis for further research to determine the influence of the novel Amoebophilaceae species on the bacterial microbiome and on vector susceptibility to and transovarial transmission of O. tsutsugamushi.}, number={12}, journal={PLOS ONE}, publisher={Public Library of Science (PLoS)}, author={Ponnusamy, Loganathan and Willcox, Alexandra C. and Roe, R. Michael and Davidson, Silas A. and Linsuwanon, Piyada and Schuster, Anthony L. and Richards, Allen L. and Meshnick, Steven R. and Apperson, Charles S.}, editor={Perotti, M. AlejandraEditor}, year={2018}, month={Dec} } @article{zhu_dhammi_kretschmar_vargo_apperson_roe_2018, title={Novel use of aliphatic n-methyl ketones as a fumigant and alternative to methyl bromide for insect control}, volume={74}, ISSN={["1526-4998"]}, DOI={10.1002/ps.4749}, abstractNote={Abstract}, number={3}, journal={PEST MANAGEMENT SCIENCE}, author={Zhu, Jiwei and Dhammi, Anirudh and Kretschmar, Jaap B. and Vargo, Edward L. and Apperson, Charles S. and Roe, R. Michael}, year={2018}, month={Mar}, pages={648–657} } @article{kakumanu_ponnusamy_sutton_meshnick_nicholson_apperson_2018, title={Prevalence of Rickettsia Species (Rickettsiales: Rickettsiaceae) in Dermacentor variabilis Ticks (Acari: Ixodidae) in North Carolina}, volume={55}, ISSN={["1938-2928"]}, url={http://dx.doi.org/10.1093/jme/tjy074}, DOI={10.1093/jme/tjy074}, abstractNote={Abstract The American dog tick, Dermacentor variabilis (Say), is a vector of spotted fever group (SFG) rickettsiae, including Rickettsia rickettsii the causative organism of Rocky Mountain spotted fever (RMSF). In North Carolina, SFG rickettsioses (including RMSF) are a leading cause of tick-borne illness. Knowledge of the infection rate and geographic distribution of D. variabilis ticks infected with Rickettsia spp. provides information on the spatial distribution of public health risk. Accordingly, we extracted genomic DNA from adult D. variabilis collected from field habitats in 32 North Carolina counties from 2009 to 2013. A nested PCR assay of the 23S-5S intergenic spacer (IGS) region of Rickettsia coupled with reverse line blot hybridization (RLBH) with species-specific probes was used to detect and identify rickettsiae to species. Approximately half of the 532 tick DNA samples exhibited a band of the expected size on agarose gels, indicating infection with Rickettsia spp. RLBH analyses showed R. amblyommatis (formerly ‘Candidatus R. amblyommii’), R. parkeri, and R. montanensis were predominant, while other Rickettsia species detected included R. conorii-like, R. massiliae, R. rhipicephali, R. canadensis, R. bellii, and some unknown Rickettsia spp. Some ticks were infected with more than one Rickettsia species. Notably, several Rickettsia-positive ticks harbored R. rickettsii. DNA sequencing was performed on a portion of the 23S-5S IGS amplicons and the results were concordant with RLB assay results. We conclude that Rickettsia spp. are common in D. variabilis in North Carolina. Geographic patterns in the occurrence of Rickettsia-infected D. variabilis ticks across the counties sampled are discussed.}, number={5}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Kakumanu, Madhavi L. and Ponnusamy, Loganathan and Sutton, Haley and Meshnick, Steven R. and Nicholson, William L. and Apperson, Charles S.}, year={2018}, month={Sep}, pages={1284–1291} } @article{bowman_akialis_cave_barrera_apperson_meshnick_2018, title={Pyrethroid insecticides maintain repellent effect on knock-down resistant populations of Aedes aegypti mosquitoes}, volume={13}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0196410}, abstractNote={Pyrethroid-treated clothing is commonly worn for protection against mosquitoes; pyrethroids are both insecticides and repellents. Pyrethroid resistance has become increasingly common in Aedes aegypti, the vector of dengue, Zika, and other arboviruses, but it is not clear whether resistance is associated with reductions in repellency. In order to determine whether long-lasting permethrin impregnated (LLPI) clothing is protective, we used Aedes aegypti from New Orleans, LA (pyrethroid-sensitive) and San Juan, PR (resistant) to measure both lethality and repellency. PCR and Sanger sequencing were used to confirm resistance status by detecting mutations in the kdr gene at positions 1016 and 1534. Arm-in-cage trials of 100 Aedes aegypti females from both populations were performed for 10 minutes to bare arm or an arm clothed in untreated military camouflage or military camouflage impregnated with deltamethrin, permethrin, or etofenprox. Trials were repeated 4–5 times on different days. Number of landings, number of blood meals, and immediate and 24-hour mortality were recorded. Mortality was extremely low in all trials. Compared to untreated cloth, mosquitoes demonstrated a trend towards a 2%-63% reduction in landings and a statistically significant 78–100% reduction in blood feeding on pyrethroid-treated cloth for most insecticides. Effects were observed in both pyrethroid-sensitive and pyrethroid-resistant mosquito populations. Our data show that kdr mutations are associated with pyrethroid resistance but are likely not the only contributors. Pyrethroids appear to maintain repellent effect against resistant mosquitoes. This finding suggests that even in places where pyrethroid resistance is widespread, permethrin still has a role for use as a repellent on clothing to protect against mosquito bites.}, number={5}, journal={PLOS ONE}, author={Bowman, Natalie M. and Akialis, Kristin and Cave, Grayson and Barrera, Roberto and Apperson, Charles S. and Meshnick, Steven R.}, year={2018}, month={May} } @misc{richards_langley_apperson_watson_2017, title={Do Tick Attachment Times Vary between Different Tick-Pathogen Systems?}, volume={4}, ISSN={["2076-3298"]}, DOI={10.3390/environments4020037}, abstractNote={Improvements to risk assessments are needed to enhance our understanding of tick-borne disease epidemiology. We review tick vectors and duration of tick attachment required for pathogen transmission for the following pathogens/toxins and diseases: (1) Anaplasma phagocytophilum (anaplasmosis); (2) Babesia microti (babesiosis); (3) Borrelia burgdorferi (Lyme disease); (4) Southern tick-associated rash illness; (5) Borrelia hermsii (tick-borne relapsing fever); (6) Borrelia parkeri (tick-borne relapsing fever); (7) Borrelia turicatae (tick-borne relapsing fever); (8) Borrelia mayonii; (9) Borrelia miyamotoi; (10) Coxiella burnetii (Query fever); (11) Ehrlichia chaffeensis (ehrlichiosis); (12) Ehrlichia ewingii (ehrlichiosis); (13) Ehrlichia muris; (14) Francisella tularensis (tularemia); (15) Rickettsia 364D; (16) Rickettsia montanensis; (17) Rickettsia parkeri (American boutonneuse fever, American tick bite fever); (18) Rickettsia ricketsii (Rocky Mountain spotted fever); (19) Colorado tick fever virus (Colorado tick fever); (20) Heartland virus; (21) Powassan virus (Powassan disease); (22) tick paralysis neurotoxin; and (23) Galactose-α-1,3-galactose (Mammalian Meat Allergy-alpha-gal syndrome). Published studies for 12 of the 23 pathogens/diseases showed tick attachment times. Reported tick attachment times varied (<1 h to seven days) between pathogen/toxin type and tick vector. Not all studies were designed to detect the duration of attachment required for transmission. Knowledge of this important aspect of vector competence is lacking and impairs risk assessment for some tick-borne pathogens.}, number={2}, journal={ENVIRONMENTS}, author={Richards, Stephanie L. and Langley, Ricky and Apperson, Charles S. and Watson, Elizabeth}, year={2017}, month={Jun} } @article{levine_apperson_levin_kelly_kakumanu_ponnusamy_sutton_salger_caldwell_szempruch_2017, title={Stable Transmission of Borrelia burgdorferi Sensu Stricto on the Outer Banks of North Carolina}, volume={64}, ISSN={1863-1959}, url={http://dx.doi.org/10.1111/zph.12302}, DOI={10.1111/zph.12302}, abstractNote={Summary}, number={5}, journal={Zoonoses and Public Health}, publisher={Wiley}, author={Levine, J. F. and Apperson, C. S. and Levin, M. and Kelly, T. R. and Kakumanu, M. L. and Ponnusamy, L. and Sutton, H. and Salger, S. A. and Caldwell, J. M. and Szempruch, A. J.}, year={2017}, month={Aug}, pages={337–354} } @article{paz-soldan_yukich_soonthorndhada_giron_apperson_ponnusamy_schal_morrison_keating_wesson_2016, title={Design and Testing of Novel Lethal Ovitrap to Reduce Populations of Aedes Mosquitoes: Community-Based Participatory Research between Industry, Academia and Communities in Peru and Thailand}, volume={11}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0160386}, DOI={10.1371/journal.pone.0160386}, abstractNote={Background Dengue virus (and Chikungunya and Zika viruses) is transmitted by Aedes aegypti and Aedes albopictus mosquitoes and causes considerable human morbidity and mortality. As there is currently no vaccine or chemoprophylaxis to protect people from dengue virus infection, vector control is the only viable option for disease prevention. The purpose of this paper is to illustrate the design and placement process for an attractive lethal ovitrap to reduce vector populations and to describe lessons learned in the development of the trap. Methods This study was conducted in 2010 in Iquitos, Peru and Lopburi Province, Thailand and used an iterative community-based participatory approach to adjust design specifications of the trap, based on community members’ perceptions and feedback, entomological findings in the lab, and design and research team observations. Multiple focus group discussions (FGD) were held over a 6 month period, stratified by age, sex and motherhood status, to inform the design process. Trap testing transitioned from the lab to within households. Results Through an iterative process of working with specifications from the research team, findings from the laboratory testing, and feedback from FGD, the design team narrowed trap design options from 22 to 6. Comments from the FGD centered on safety for children and pets interacting with traps, durability, maintenance issues, and aesthetics. Testing in the laboratory involved releasing groups of 50 gravid Ae. aegypti in walk-in rooms and assessing what percentage were caught in traps of different colors, with different trap cover sizes, and placed under lighter or darker locations. Two final trap models were mocked up and tested in homes for a week; one model was the top choice in both Iquitos and Lopburi. Discussion The community-based participatory process was essential for the development of novel traps that provided effective vector control, but also met the needs and concerns of community members.}, number={8}, journal={PLOS ONE}, publisher={Public Library of Science (PLoS)}, author={Paz-Soldan, Valerie A. and Yukich, Josh and Soonthorndhada, Amara and Giron, Maziel and Apperson, Charles S. and Ponnusamy, Loganathan and Schal, Coby and Morrison, Amy C. and Keating, Joseph and Wesson, Dawn M.}, editor={Paul, RichardEditor}, year={2016}, month={Aug}, pages={e0160386} } @article{kakumanu_ponnusamy_sutton_meshnick_nicholson_apperson_2016, title={Development and Validation of an Improved PCR Method Using the 23S-5S Intergenic Spacer for Detection of Rickettsiae in Dermacentor variabilis Ticks and Tissue Samples from Humans and Laboratory Animals}, volume={54}, ISSN={["1098-660X"]}, url={http://dx.doi.org/10.1128/jcm.02605-15}, DOI={10.1128/jcm.02605-15}, abstractNote={ABSTRACT}, number={4}, journal={JOURNAL OF CLINICAL MICROBIOLOGY}, author={Kakumanu, Madhavi L. and Ponnusamy, Loganathan and Sutton, Haley T. and Meshnick, Steven R. and Nicholson, William L. and Apperson, Charles S.}, year={2016}, month={Apr}, pages={972–979} } @article{choi_grieco_apperson_schal_ponnusamy_wesson_achee_2016, title={Effect of Spatial Repellent Exposure on Dengue Vector Attraction to Oviposition Sites}, volume={10}, ISSN={1935-2735}, url={http://dx.doi.org/10.1371/journal.pntd.0004850}, DOI={10.1371/journal.pntd.0004850}, abstractNote={Background Aedes aegypti is a primary vector of dengue virus (DENV), the causative agent of dengue fever, an arthropod-borne disease of global importance. Although a vaccine has been recommended for prevention, current dengue prevention strategies rely on vector control. Recently, volatile pyrethroids—spatial repellents—have received interest as a novel delivery system for adult Ae. aegypti control. Understanding the full range of behavioral effects spatial repellents elicit in mosquito species will be critical to understanding the overall impact these products have on vector populations and will guide expectations of efficacy against DENV transmission. Methodology/Principal Findings The current study quantified changes in attraction of gravid Ae. aegypti to experimental oviposition sites following exposure to the spatial repellent transfluthrin. Responses were measured with two-choice olfaction bioassays using ‘sticky-screens’ covering cups to prevent contact with the oviposition substrate. Two cups contained a bacterial attractant composed of four species of bacteria in calcium alginate beads in water and two cups contained only deionized water. Results from 40 replicates (n = 780 females total per treatment) indicated an estimated difference in attraction of 9.35% ± 0.18 (p ≤ 0.003), implying that the transfluthrin-exposed mosquitoes were more attracted to the experimental oviposition sites than the non-exposed mosquitoes. Conclusions/Significance Findings from this study will further characterize the role of spatial repellents to modify Ae. aegypti behavior related to dengue prevention specifically, and encourage innovation in vector control product development more broadly.}, number={7}, journal={PLOS Neglected Tropical Diseases}, publisher={Public Library of Science (PLoS)}, author={Choi, Diane B. and Grieco, John P. and Apperson, Charles S. and Schal, Coby and Ponnusamy, Loganathan and Wesson, Dawn M. and Achee, Nicole L.}, editor={Kittayapong, PattamapornEditor}, year={2016}, month={Jul}, pages={e0004850} } @article{wallace_nicholson_perniciaro_vaughn_funkhouser_juliano_lee_kakumanu_ponnusamy_apperson_et al._2016, title={Incident Tick-Borne Infections in a Cohort of North Carolina Outdoor Workers}, volume={16}, ISSN={["1557-7759"]}, url={http://dx.doi.org/10.1089/vbz.2015.1887}, DOI={10.1089/vbz.2015.1887}, abstractNote={Tick-borne diseases cause substantial morbidity throughout the United States, and North Carolina has a high incidence of spotted fever rickettsioses and ehrlichiosis, with sporadic cases of Lyme disease. The occupational risk of tick-borne infections among outdoor workers is high, particularly those working on publicly managed lands. This study identified incident tick-borne infections and examined seroconversion risk factors among a cohort of North Carolina outdoor workers. Workers from the North Carolina State Divisions of Forestry, Parks and Recreation, and Wildlife (n = 159) were followed for 2 years in a randomized controlled trial evaluating the effectiveness of long-lasting permethrin-impregnated clothing. Antibody titers against Rickettsia parkeri, Rickettsia rickettsii, "Rickettsia amblyommii," and Ehrlichia chaffeensis were measured at baseline (n = 130), after 1 year (n = 82), and after 2 years (n = 73). Titers against Borrelia burgdorferi were measured at baseline and after 2 years (n = 90). Baseline seroprevalence, defined as indirect immunofluorescence antibody titers of 1/128 or greater, was R. parkeri (24%), R. rickettsii (19%), "R. amblyommii" (12%), and E. chaffeensis (4%). Incident infection was defined as a fourfold increase in titer over a 1-year period. There were 40 total seroconversions to at least one pathogen, including R. parkeri (n = 19), "R. amblyommii" (n = 14), R. rickettsii (n = 9), and E. chaffeensis (n = 8). There were no subjects whose sera were reactive to B. burgdorferi C6 antigen. Thirty-eight of the 40 incident infections were subclinical. The overall risk of infection by any pathogen during the study period was 0.26, and the risk among the NC Division of Forest Resources workers was 1.73 times that of workers in other divisions (95% confidence interval [CI]: 1.02, 2.92). The risk of infection was lower in subjects wearing permethrin-impregnated clothing, but not significantly (risk ratio = 0.81; 95% CI: 0.47, 1.39). In summary, outdoor workers in North Carolina are at high risk of incident tick-borne infections, most of which appear to be asymptomatic.}, number={5}, journal={VECTOR-BORNE AND ZOONOTIC DISEASES}, author={Wallace, John W. and Nicholson, William L. and Perniciaro, Jamie L. and Vaughn, Meagan F. and Funkhouser, Sheana and Juliano, Jonathan J. and Lee, Sangmi and Kakumanu, Madhavi L. and Ponnusamy, Loganathan and Apperson, Charles S. and et al.}, year={2016}, month={May}, pages={302–308} } @article{marayati_schal_ponnusamy_apperson_rowland_wasserberg_2015, title={Attraction and oviposition preferences of Phlebotomus papatasi (Diptera: Psychodidae), vector of Old-World cutaneous leishmaniasis, to larval rearing media}, volume={8}, ISSN={1756-3305}, url={http://dx.doi.org/10.1186/s13071-015-1261-z}, DOI={10.1186/s13071-015-1261-z}, abstractNote={As part of a project aimed at developing oviposition attractants for the control and surveillance of Phlebotomus papatasi (a vector of Old-World cutaneous leishmaniasis), we tested the hypothesis that gravid sand flies are attracted to chemical cues emanating from the growth medium of conspecific larvae - predominantly larvae-conditioned host feces that represents a suitable oviposition site. We report the results of a systematic assessment of media from various developmental stages of the sand fly using oviposition and olfactometer behavioral assays.We conducted multiple-choice oviposition assays in 500 mL Nalgene jars. Six treatments were placed on separate filter paper discs at the bottom of the jar: 2(nd)/3(rd) larval instar medium, 4(th) larval instar/pupae medium, frass from expired colonies, larval food (aged rabbit chow and rabbit feces mix), rabbit feces, and a solvent (water) control. Fifty gravid females were introduced into each jar. Cumulative number of eggs laid on each filter paper per jar was counted at different time intervals from digital images. Attraction of gravid sand flies to these six treatments was assayed with a 3-chamber linear olfactometer. Twenty gravid females were transferred to the middle chamber of the olfactometer and their distribution in treatment and control chambers was recorded after 3 h.Almost no eggs were oviposited during the first 72 h following a blood-meal. Cumulative egg deposition increased drastically in the next 24 h (hours 73-96), with a slight non-significant increasing trend thereafter. Comparing mean cumulative egg deposition among the six treatments, we found that significantly more eggs were oviposited on 2(nd)/3(rd) larval rearing medium followed by 4(th) instar/pupae rearing medium. Oviposition preference did not vary over time. The olfactometer results were consistent with the oviposition assays, with 2(nd)/3(rd) larval rearing medium being the most attractive, followed by 4(th) instar/pupae rearing medium.The key finding of this study is that gravid, laboratory reared, Ph. papatasi sand flies are significantly more attracted to rearing medium of the most biologically active larval stages (2(nd)/3(rd) instar and 4(th) instar/pupae). This finding indicates that sand fly-digested host food and feces is attractive to gravid females and suggests that the larvae and larval gut microbiome may be involved in conditioning the oviposition substrate and possibly the production of oviposition attractants and stimulants.}, number={1}, journal={Parasites & Vectors}, publisher={Springer Science and Business Media LLC}, author={Marayati, Bahjat Fadi and Schal, Coby and Ponnusamy, Loganathan and Apperson, Charles S. and Rowland, Tobin E. and Wasserberg, Gideon}, year={2015}, month={Dec} } @article{ponnusamy_schal_wesson_arellano_apperson_2015, title={Oviposition responses of Aedes mosquitoes to bacterial isolates from attractive bamboo infusions}, volume={8}, journal={Parasites & Vectors}, author={Ponnusamy, L. and Schal, C. and Wesson, D. M. and Arellano, C. and Apperson, C. S.}, year={2015} } @article{van treuren_ponnusamy_brinkerhoff_gonzalez_parobek_juliano_andreadis_falco_ziegler_hathaway_et al._2015, title={Variation in the Microbiota of Ixodes Ticks with Regard to Geography, Species, and Sex}, volume={81}, ISSN={["1098-5336"]}, url={http://dx.doi.org/10.1128/aem.01562-15}, DOI={10.1128/aem.01562-15}, abstractNote={ABSTRACT}, number={18}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Van Treuren, Will and Ponnusamy, Loganathan and Brinkerhoff, R. Jory and Gonzalez, Antonio and Parobek, Christian M. and Juliano, Jonathan J. and Andreadis, Theodore G. and Falco, Richard C. and Ziegler, Lorenza Beati and Hathaway, Nicholas and et al.}, year={2015}, month={Sep}, pages={6200–6209} } @article{ponnusamy_gonzalez_van treuren_weiss_parobek_juliano_knight_roe_apperson_meshnickh_2014, title={Diversity of Rickettsiales in the Microbiome of the Lone Star Tick, Amblyomma americanum}, volume={80}, ISSN={["1098-5336"]}, url={http://dx.doi.org/10.1128/aem.02987-13}, DOI={10.1128/aem.02987-13}, abstractNote={ABSTRACT}, number={1}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Ponnusamy, Loganathan and Gonzalez, Antonio and Van Treuren, Will and Weiss, Sophie and Parobek, Christian M. and Juliano, Jonathan J. and Knight, Rob and Roe, R. Michael and Apperson, Charles S. and Meshnickh, Steven R.}, year={2014}, month={Jan}, pages={354–359} } @article{vaughn_funkhouser_lin_fine_juliano_apperson_meshnick_2014, title={Long-lasting Permethrin Impregnated Uniforms A Randomized-Controlled Trial for Tick Bite Prevention}, volume={46}, ISSN={["1873-2607"]}, DOI={10.1016/j.amepre.2014.01.008}, abstractNote={BackgroundBecause of frequent exposure to tick habitats, outdoor workers are at high risk for tick-borne diseases. Adherence to National Institute for Occupational Safety and Health−recommended tick bite prevention methods is poor. A factory-based method for permethrin impregnation of clothing that provides long-lasting insecticidal and repellent activity is commercially available, and studies are needed to assess the long-term effectiveness of this clothing under field conditions.PurposeTo evaluate the protective effectiveness of long-lasting permethrin impregnated uniforms among a cohort of North Carolina outdoor workers.Design, setting, and participantsA double-blind RCT was conducted between March 2011 and September 2012. Subjects included outdoor workers from North Carolina State Divisions of Forestry, Parks and Recreation, and Wildlife who worked in eastern or central North Carolina. A total of 159 volunteer subjects were randomized, and 127 and 101 subjects completed the first and second years of follow-up, respectively.InterventionUniforms of participants in the treatment group were factory-impregnated with long-lasting permethrin whereas control group uniforms received a sham treatment. Participants continued to engage in their usual tick bite prevention activities.Main outcome measuresIncidence of work-related tick bites reported on weekly tick bite logs.ResultsStudy subjects reported 1,045 work-related tick bites over 5,251 person-weeks of follow-up. The mean number of reported tick bites in the year prior to enrollment was similar for both the treatment and control groups, but markedly different during the study period. In our analysis conducted in 2013, the effectiveness of long-lasting permethrin impregnated uniforms for the prevention of work-related tick bites was 0.82 (95% CI=0.66, 0.91) and 0.34 (95% CI=−0.67, 0.74) for the first and second years of follow-up.ConclusionsThese results indicate that long-lasting permethrin impregnated uniforms are highly effective for at least 1 year in deterring tick bites in the context of typical tick bite prevention measures employed by outdoor workers. Because of frequent exposure to tick habitats, outdoor workers are at high risk for tick-borne diseases. Adherence to National Institute for Occupational Safety and Health−recommended tick bite prevention methods is poor. A factory-based method for permethrin impregnation of clothing that provides long-lasting insecticidal and repellent activity is commercially available, and studies are needed to assess the long-term effectiveness of this clothing under field conditions. To evaluate the protective effectiveness of long-lasting permethrin impregnated uniforms among a cohort of North Carolina outdoor workers. A double-blind RCT was conducted between March 2011 and September 2012. Subjects included outdoor workers from North Carolina State Divisions of Forestry, Parks and Recreation, and Wildlife who worked in eastern or central North Carolina. A total of 159 volunteer subjects were randomized, and 127 and 101 subjects completed the first and second years of follow-up, respectively. Uniforms of participants in the treatment group were factory-impregnated with long-lasting permethrin whereas control group uniforms received a sham treatment. Participants continued to engage in their usual tick bite prevention activities. Incidence of work-related tick bites reported on weekly tick bite logs. Study subjects reported 1,045 work-related tick bites over 5,251 person-weeks of follow-up. The mean number of reported tick bites in the year prior to enrollment was similar for both the treatment and control groups, but markedly different during the study period. In our analysis conducted in 2013, the effectiveness of long-lasting permethrin impregnated uniforms for the prevention of work-related tick bites was 0.82 (95% CI=0.66, 0.91) and 0.34 (95% CI=−0.67, 0.74) for the first and second years of follow-up. These results indicate that long-lasting permethrin impregnated uniforms are highly effective for at least 1 year in deterring tick bites in the context of typical tick bite prevention measures employed by outdoor workers.}, number={5}, journal={AMERICAN JOURNAL OF PREVENTIVE MEDICINE}, author={Vaughn, Meagan F. and Funkhouser, Sheana Whelan and Lin, Feng-Chang and Fine, Jason and Juliano, Jonathan J. and Apperson, Charles S. and Meshnick, Steven R.}, year={2014}, month={May}, pages={473–480} } @article{lee_kakumanu_ponnusamy_vaughn_funkhouser_thornton_meshnick_apperson_2014, title={Prevalence of Rickettsiales in ticks removed from the skin of outdoor workers in North Carolina}, volume={7}, ISSN={["1756-3305"]}, url={http://dx.doi.org/10.1186/s13071-014-0607-2}, DOI={10.1186/s13071-014-0607-2}, abstractNote={Tick-transmitted rickettsial diseases, such as ehrlichiosis and spotted fever rickettsiosis, are significant sources of morbidity and mortality in the southern United States. Because of their exposure in tick-infested woodlands, outdoor workers experience an increased risk of infection with tick-borne pathogens. As part of a double blind randomized-controlled field trial of the effectiveness of permethrin-treated clothing in preventing tick bites, we identified tick species removed from the skin of outdoor workers in North Carolina and tested the ticks for Rickettsiales pathogens.Ticks submitted by study participants from April-September 2011 and 2012 were identified to species and life stage, and preliminarily screened for the genus Rickettsia by nested PCR targeting the 17-kDa protein gene. Rickettsia were further identified to species by PCR amplification of 23S-5S intergenic spacer (IGS) fragments combined with reverse line blot hybridization with species-specific probes and through cloning and nucleotide sequence analysis of 23S-5S amplicons. Ticks were examined for Ehrlichia and Anaplasma by nested PCR directed at the gltA, antigen-expressing gene containing a variable number of tandem repeats, 16S rRNA, and groESL genes.The lone star tick (Amblyomma americanum) accounted for 95.0 and 92.9% of ticks submitted in 2011 (n = 423) and 2012 (n = 451), respectively. Specimens of American dog tick (Dermacentor variabilis), Gulf Coast tick (Amblyomma maculatum) and black-legged tick (Ixodes scapularis) were also identified. In both years of our study, 60.9% of ticks tested positive for 17-kDa. "Candidatus Rickettsia amblyommii", identified in all four tick species, accounted for 90.2% (416/461) of the 23S-5S-positive samples and 52.9% (416/787) of all samples tested. Nucleotide sequence analysis of Rickettsia-specific 23S-5S IGS, ompA and gltA gene fragments indicated that ticks, principally A. americanum, contained novel species of Rickettsia. Other Rickettsiales, including Ehrlichia ewingii, E. chaffeensis, Ehrlichia sp. (Panola Mountain), and Anaplasma phagocytophilum, were infrequently identified, principally in A. americanum.We conclude that in North Carolina, the most common rickettsial exposure is to R. amblyommii carried by A. americanum. Other Rickettsiales bacteria, including novel species of Rickettsia, were less frequently detected in A. americanum but are relevant to public health nevertheless.}, journal={PARASITES & VECTORS}, author={Lee, Sangmi and Kakumanu, Madhavi L. and Ponnusamy, Loganathan and Vaughn, Meagan and Funkhouser, Sheana and Thornton, Haley and Meshnick, Steven R. and Apperson, Charles S.}, year={2014}, month={Dec} } @article{stell_roe_arellano_apperson_2013, title={Innovative Sugar-Insecticide Feeding Bioassay for Adult Female Anopheles gambiae (Diptera: Culicidae)}, volume={50}, ISSN={["1938-2928"]}, DOI={10.1603/me12213}, abstractNote={ABSTRACT The primary malaria vector in sub-Saharan Africa, Anopheles gambiae Giles (Diptera: Culicidae), is an anthropophagic and endophilic mosquito targeted for control with insecticides applied to interior resting surfaces and impregnated onto bed net materials. Effective malaria vector management involves monitoring the insecticide susceptibility of mosquito populations. Contemporary bioassays are based on mosquito contact with insecticide residues. We developed an innovative insecticide bioassay system that involves mosquito ingestion of a sugar-insecticide solution. The sucrose—permethrin solution in our bioassay system contained Trypan blue dye, creating a visual marker of insecticide ingestion in the mosquito's abdomen. Blue fecal spots deposited in the bioassay container provided further evidence of mosquito feeding. We used our bioassay to characterize the permethrin susceptibility of adult females of two strains of A. gambiae, one of which was susceptible and the other exhibited reduced susceptibility to permethrin. We compared the dose-response of both strains to permethrin in a forced-contact filter paper bioassay. Both assay approaches produced similar dose-dependent mortality, indicating that the feeding bioassay had appropriately characterized permethrin susceptibility for both mosquito strains.}, number={4}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Stell, F. M. and Roe, R. M. and Arellano, C. and Apperson, C. S.}, year={2013}, month={Jul}, pages={804–815} } @article{stell_roe_arellano_kennedy_thornton_saavedra-rodriguez_wesson_black_apperson_2013, title={Proof of concept for a novel insecticide bioassay based on sugar feeding by adult Aedes aegypti (Stegomyia aegypti)}, volume={27}, ISSN={["1365-2915"]}, DOI={10.1111/j.1365-2915.2012.01048.x}, abstractNote={Aedes aegypti L. (Stegomyia aegypti) (Diptera: Culicidae) is the principal vector of dengue and yellow fever viruses in tropical and subtropical regions of the world. Disease management is largely based on mosquito control achieved by insecticides applied to interior resting surfaces and through space sprays. Population monitoring to detect insecticide resistance is a significant component of integrated disease management programmes. We developed a bioassay method for assessing insecticide susceptibility based on the feeding activity of mosquitoes on plant sugars. Our prototype sugar‐insecticide feeding bioassay system was composed of inexpensive, disposable components, contained minimal volumes of insecticide, and was compact and highly transportable. Individual mosquitoes were assayed in a plastic cup that contained a sucrose‐permethrin solution. Trypan blue dye was added to create a visual marker in the mosquito's abdomen for ingested sucrose‐permethrin solution. Blue faecal spots provided further evidence of solution ingestion. With the sugar‐insecticide feeding bioassay, the permethrin susceptibility of Ae. aegypti females from two field‐collected strains was characterized by probit analysis of dosage‐response data. The field strains were also tested by forced contact of females with permethrin residues on filter paper. Dosage‐response patterns were similar, indicating that the sugar‐insecticide feeding bioassay had appropriately characterized the permethrin susceptibility of the two strains.}, number={3}, journal={MEDICAL AND VETERINARY ENTOMOLOGY}, author={Stell, F. M. and Roe, R. M. and Arellano, C. and Kennedy, L. and Thornton, H. and Saavedra-Rodriguez, K. and Wesson, D. M. and Black, W. C. and Apperson, C. S.}, year={2013}, month={Sep}, pages={284–297} } @article{carr_roe_arellano_sonenshine_schal_apperson_2013, title={Responses of Amblyomma americanum and Dermacentor variabilisto odorants that attract haematophagous insects}, volume={27}, ISSN={0269-283X}, url={http://dx.doi.org/10.1111/j.1365-2915.2012.01024.x}, DOI={10.1111/j.1365-2915.2012.01024.x}, abstractNote={Carbon dioxide (CO2), 1‐octen‐3‐ol, acetone, ammonium hydroxide, L‐lactic‐acid, dimethyl trisulphide and isobutyric acid were tested as attractants for two tick species, Amblyomma americanum and Dermacentor variabilis (Acari: Ixodidae), in dose–response bioassays using Y‐tube olfactometers. Only CO2, acetone, 1‐octen‐3‐ol and ammonium hydroxide elicited significant preferences from adult A. americanum, and only CO2 was attractive to adult D. variabilis. Acetone, 1‐octen‐3‐ol and ammonium hydroxide were separately evaluated at three doses against CO2 (from dry ice) at a field site supporting a natural population of A. americanum nymphs and adults. Carbon dioxide consistently attracted the highest number of host‐seeking ticks. However, for the first time, acetone, 1‐octen‐3‐ol and ammonium hydroxide were shown to attract high numbers of A. americanum. Further research is needed to determine the utility of these semiochemicals as attractants in tick surveillance and area‐wide management programmes.}, number={1}, journal={Medical and Veterinary Entomology}, publisher={Wiley}, author={Carr, A. L. and Roe, R. M. and Arellano, C. and Sonenshine, D. E. and Schal, C. and Apperson, C. S.}, year={2013}, month={Mar}, pages={86–95} } @article{walsh_bradley_apperson_gould_2012, title={An Experimental Field Study of Delayed Density Dependence in Natural Populations of Aedes albopictus}, volume={7}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0035959}, abstractNote={Aedes albopictus, a species known to transmit dengue and chikungunya viruses, is primarily a container-inhabiting mosquito. The potential for pathogen transmission by Ae. albopictus has increased our need to understand its ecology and population dynamics. Two parameters that we know little about are the impact of direct density-dependence and delayed density-dependence in the larval stage. The present study uses a manipulative experimental design, under field conditions, to understand the impact of delayed density dependence in a natural population of Ae. albopictus in Raleigh, North Carolina. Twenty liter buckets, divided in half prior to experimentation, placed in the field accumulated rainwater and detritus, providing oviposition and larval production sites for natural populations of Ae. albopictus. Two treatments, a larvae present and larvae absent treatment, were produced in each bucket. After five weeks all larvae were removed from both treatments and the buckets were covered with fine mesh cloth. Equal numbers of first instars were added to both treatments in every bucket. Pupae were collected daily and adults were frozen as they emerged. We found a significant impact of delayed density-dependence on larval survival, development time and adult body size in containers with high larval densities. Our results indicate that delayed density-dependence will have negative impacts on the mosquito population when larval densities are high enough to deplete accessible nutrients faster than the rate of natural food accumulation.}, number={4}, journal={PLOS ONE}, author={Walsh, Rachael K. and Bradley, Caitlin and Apperson, Charles S. and Gould, Fred}, year={2012}, month={Apr} } @article{ponnusamy_böröczky_wesson_schal_apperson_2011, title={Bacteria Stimulate Hatching of Yellow Fever Mosquito Eggs}, volume={6}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0024409}, DOI={10.1371/journal.pone.0024409}, abstractNote={Background Aedes aegypti Linnaeus is a peridomestic mosquito that lays desiccation-resistant eggs in water-filled human-made containers. Previous investigations connected egg hatching with declining dissolved oxygen (DO) that is associated with bacterial growth. However, past studies failed to uncouple DO from other potential stimulatory factors and they contained little quantitative information about the microbial community; consequently, a direct role for bacteria or compounds associated with bacteria in stimulating egg hatching cannot be dismissed. Methodology/Principal Findings Environmental factors stimulating hatch of Ae. aegypti eggs were investigated using non-sterile and sterile white oak leaf (WOL) infusions and a bacterial culture composed of a mix of 14 species originally isolated from bamboo leaf infusion. In WOL infusion with active microbes, 92.4% of eggs hatched in 2-h at an average DO concentration of 2.4 ppm. A 24-h old bacterial culture with a DO concentration of 0.73 ppm also stimulated 95.2% of eggs hatch within 1-h. In contrast, only 4.0% of eggs hatched in sterile infusion, whose DO averaged 7.4 ppm. Effects of bacteria were uncoupled from DO by exposing eggs to bacterial cells suspended in NaCl solution. Over a 4-h exposure period, 93.8% of eggs hatched while DO concentration changed minimally from 7.62 to 7.50 ppm. Removal of bacteria by ultra-filtration and cell-free filtrate resulted in only 52.0% of eggs hatching after 4-h at an average DO concentration of 5.5 ppm. Conclusions/Significance Collectively, the results provide compelling evidence that bacteria or water-soluble compounds secreted by bacteria, not just low DO concentration, stimulate hatching of Ae. aegypti eggs. However, the specific cues involved remain to be identified. These research findings contribute new insight into an important aspect of the oviposition biology of Ae. aegypti, a virus vector of global importance, providing the basis for a new paradigm of environmental factors involved in egg hatching.}, number={9}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Ponnusamy, Loganathan and Böröczky, Katalin and Wesson, Dawn M. and Schal, Coby and Apperson, Charles S.}, editor={Leulier, FrançoisEditor}, year={2011}, month={Sep}, pages={e24409} } @article{kimps_bissinger_apperson_sonenshine_roe_2011, title={First report of the repellency of 2-tridecanone against ticks}, volume={25}, ISSN={["1365-2915"]}, DOI={10.1111/j.1365-2915.2010.00918.x}, abstractNote={2‐Tridecanone and 2‐undecanone are both found naturally in the trichomes of wild tomato plants and are important in plant resistance to herbivory. 2‐Undecanone is the U.S. Environmental Protection Agency (EPA)‐registered active ingredient in the commercially available arthropod repellent, BioUD®. The goal of this study was to examine the tick repellency of 2‐tridecanone. Two‐choice bioassays were conducted using 8% 2‐tridecanone vs. the repellent carrier (absolute ethanol) and compared with two‐choice studies using 8% 2‐undecanone vs. absolute ethanol. Unfed, host‐seeking adult (mixed sex) Amblyomma americanum (L.) (Acari: Ixodidae) and Dermacentor variabilis Say (Acari: Ixodidae) were used to evaluate repellency and time to repellent failure at room temperature. The present study shows in filter paper assays (0.63 mg test compound/cm2) that 2‐tridecanone was 87% repellent to A. americanum at 12 h after application, but had no statistically significant repellency at 15 h and 24 h, and was 72% repellent to D. variabilis at 15 h, but had no statistically significant repellency at 24 h. By contrast, 2‐undecanone was 74% and 75% repellent to A. americanum and D. variabilis, respectively, at 2 h after application, but no statistically significant repellency was noted at 2.5 h and 3 h. In two‐choice assays on cheesecloth, 2‐tridecanone at 0.25 mg/cm2 was 85% repellent to A. americanum 6 h after application, demonstrating its potential use as an arthropod repellent that can be used on clothing without the need for formulation. No statistically significant repellency was found at 9 h or 12 h. The potential use of 2‐tridecanone as a tick repellent is discussed.}, number={2}, journal={MEDICAL AND VETERINARY ENTOMOLOGY}, author={Kimps, N. W. and Bissinger, B. W. and Apperson, C. S. and Sonenshine, D. E. and Roe, R. M.}, year={2011}, month={Jun}, pages={202–208} } @article{nojima_kiemle_webster_apperson_schal_2011, title={Nanogram-Scale Preparation and NMR Analysis for Mass-Limited Small Volatile Compounds}, volume={6}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0018178}, DOI={10.1371/journal.pone.0018178}, abstractNote={Semiochemicals are often produced in infinitesimally small quantities, so their isolation requires large amounts of starting material, not only requiring significant effort in sample preparation, but also resulting in a complex mixture of compounds from which the bioactive compound needs to be purified and identified. Often, compounds cannot be unambiguously identified by their mass spectra alone, and NMR analysis is required for absolute chemical identification, further exacerbating the situation because NMR is relatively insensitive and requires large amounts of pure analyte, generally more than several micrograms. We developed an integrated approach for purification and NMR analysis of <1 µg of material. Collections from high performance preparative gas-chromatography are directly eluted with minimal NMR solvent into capillary NMR tubes. With this technique, 1H-NMR spectra were obtained on 50 ng of geranyl acetate, which served as a model compound, and reasonable H-H COSY NMR spectra were obtained from 250 ng of geranyl acetate. This simple off-line integration of preparative GC and NMR will facilitate the purification and chemical identification of novel volatile compounds, such as insect pheromones and other semiochemicals, which occur in minute (sub-nanogram), and often limited, quantities.}, number={3}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Nojima, Satoshi and Kiemle, David J. and Webster, Francis X. and Apperson, Charles S. and Schal, Coby}, editor={Leal, WalterEditor}, year={2011}, month={Mar}, pages={e18178} } @article{bissinger_apperson_watson_arellano_sonenshine_roe_2011, title={Novel field assays and the comparative repellency of BioUD (R), DEET and permethrin against Amblyomma americanum}, volume={25}, ISSN={["1365-2915"]}, DOI={10.1111/j.1365-2915.2010.00923.x}, abstractNote={Two new field bioassay methods were developed to compare the repellent activity of BioUD® (containing 7.75% 2‐undecanone), 98.1% DEET and 0.5% permethrin against natural populations of nymphal Amblyomma americanum (L.) (Acari: Ixodidae). In a cloth sheet assay, pieces of material measuring 41 × 58 cm, separately treated with one of the test materials or the appropriate solvent carrier, were placed at random on the ground and baited with dry ice for 1 h. Mean numbers of ticks on repellent‐treated sheets were significantly lower than on control sheets. There was no significant difference in the number of ticks collected between sheets treated with BioUD® and those treated with DEET. However, significantly fewer ticks were found on sheets treated with BioUD® or DEET than on permethrin‐treated sheets. In a sock test, over‐the‐calf tube socks were treated with one of the test materials or the appropriate solvent carrier. Human volunteers wore a repellent‐treated and a corresponding carrier‐treated sock on either leg and walked randomly over an area of approximately 4000 m2 for 15 min. Significantly fewer ticks were collected from socks treated with BioUD® or DEET than from socks treated with the carrier and there was no significant difference in repellency between these two agents. No difference in the mean number of ticks collected was found between permethrin‐treated and corresponding carrier‐treated socks. To examine the mechanism of repellency of BioUD®, a four‐choice olfactometer was used to assess spatial repellency against adult A. americanum. As expected in the absence of a repellent, when all choices were represented by water‐treated filter paper, ticks were equally distributed among the choices. When one choice consisted of BioUD®‐treated filter paper and the remaining choices of water‐treated paper, the distribution of ticks on the repellent‐treated paper was significantly lower than might be expected to occur by chance, suggesting that repellency is at least partly achieved by an olfactory mechanism.}, number={2}, journal={MEDICAL AND VETERINARY ENTOMOLOGY}, author={Bissinger, B. W. and Apperson, C. S. and Watson, D. W. and Arellano, C. and Sonenshine, D. E. and Roe, R. M.}, year={2011}, month={Jun}, pages={217–226} } @article{ponnusamy_xu_böröczky_wesson_abu ayyash_schal_apperson_2010, title={Oviposition Responses of the Mosquitoes Aedes aegypti and Aedes albopictus to Experimental Plant Infusions in Laboratory Bioassays}, volume={36}, ISSN={0098-0331 1573-1561}, url={http://dx.doi.org/10.1007/s10886-010-9806-2}, DOI={10.1007/s10886-010-9806-2}, abstractNote={Attraction of the mosquitoes Aedes aegypti and Ae. albopictus to plant infusions was evaluated by using a modified sticky-screen bioassay that improved the resolution of mosquito responses to odorants. Under bioassay conditions, solid-phase microextraction-gas chromatographic analyses of the volatile marker chemical indole showed that odorants diffused from bioassay cups, forming a concentration gradient. Infusions were prepared by separately fermenting senescent leaves of eight plant species in well water. Plant infusions were evaluated over an 8-fold range of leaf biomass and/or a 28 d fermentation period. The responses of gravid females of both mosquito species varied with the plant species and biomass of plant materials used to make infusions, and with the length of the fermentation period. Infusions made from senescent bamboo (Arundinaria gigantea) and white oak (Quercus alba) leaves were significantly attractive to both mosquitoes. In general, infusions prepared by using low biomass of plant material over a 7–14 d fermentation period were most attractive to Ae. aegypti. In contrast, Ae. albopictus was attracted to infusions made using a wider range of plant biomass and over a longer fermentation period. Both mosquito species were more attracted to a non-sterile white oak leaf infusion than to white oak leaf infusion that was prepared using sterilized plant material and water, thus suggesting a role for microbial activity in the production of odorants that mediate the oviposition response of gravid mosquitoes.}, number={7}, journal={Journal of Chemical Ecology}, publisher={Springer Science and Business Media LLC}, author={Ponnusamy, Loganathan and Xu, Ning and Böröczky, Katalin and Wesson, Dawn M. and Abu Ayyash, Luma and Schal, Coby and Apperson, Charles S.}, year={2010}, month={Jun}, pages={709–719} } @article{ponnusamy_wesson_arellano_schal_apperson_2010, title={Species Composition of Bacterial Communities Influences Attraction of Mosquitoes to Experimental Plant Infusions}, volume={59}, ISSN={0095-3628 1432-184X}, url={http://dx.doi.org/10.1007/s00248-009-9565-1}, DOI={10.1007/s00248-009-9565-1}, abstractNote={In the container habitats of immature mosquitoes, catabolism of plant matter and other organic detritus by microbial organisms produces metabolites that mediate the oviposition behavior of Aedes aegypti and Aedes albopictus. Public health agencies commonly use oviposition traps containing plant infusions for monitoring populations of these mosquito species, which are global vectors of dengue viruses. In laboratory experiments, gravid females exhibited significantly diminished responses to experimental infusions made with sterilized white oak leaves, showing that attractive odorants were produced through microbial metabolic activity. We evaluated effects of infusion concentration and fermentation time on attraction of gravid females to infusions made from senescent bamboo or white oak leaves. We used plate counts of heterotrophic bacteria, total counts of 4′,6-diamidino-2-phenylindole-stained bacterial cells, and 16S ribosomal DNA (rDNA) polymerase chain reaction–denaturing gradient gel electrophoresis (DGGE) to show that changes in the relative abundance of bacteria and the species composition of bacterial communities influenced attraction of gravid A. aegypti and A. albopictus mosquitoes to infusions. DGGE profiles showed that bacterial species composition in infusions changed over time. Principal components analysis indicated that oviposition responses to plant infusions were in general most affected by bacterial diversity and abundance. Analysis of bacterial 16S rDNA sequences derived from DGGE bands revealed that Proteobacteria (Alpha-, Beta-, Delta-, and Gamma-) were the predominant bacteria detected in both types of plant infusions. Gravid A. aegypti were significantly attracted to a mix of 14 bacterial species cultured from bamboo leaf infusion. The oviposition response of gravid mosquitoes to plant infusions is strongly influenced by abundance and diversity of bacterial species, which in turn is affected by plant species, leaf biomass, and fermentation time.}, number={1}, journal={Microbial Ecology}, publisher={Springer Science and Business Media LLC}, author={Ponnusamy, Loganathan and Wesson, Dawn M. and Arellano, Consuelo and Schal, Coby and Apperson, Charles S.}, year={2010}, month={Jan}, pages={158–173} } @article{bissinger_zhu_apperson_sonenshine_watson_roe_2009, title={Comparative Efficacy of BioUD to Other Commercially Available Arthropod Repellents against the Ticks Amblyomma americanum and Dermacentor variabilis on Cotton Cloth}, volume={81}, ISSN={["1476-1645"]}, DOI={10.4269/ajtmh.2009.09-0114}, abstractNote={BioUD is an arthropod repellent that contains the active ingredient 2-undecanone originally derived from wild tomato plants. Repellency of BioUD was compared with five commercially available arthropod repellents against the ticks Amblyomma americanum (L.) and Dermacentor variabilis Say in two-choice bioassays on treated versus untreated cotton cheesecloth. Overall mean percentage repellency against both species was greatest for and did not differ significantly between BioUD (7.75% 2-undecanone) and products containing 98.1% DEET, 19.6% IR3535, and 30% oil of lemon eucalyptus. Products containing 5% and 15% Picaridin and 0.5% permethrin were also repellent compared with untreated controls but to a lesser degree than BioUD. The four most active repellents at the same concentrations used before were directly compared in head-to-head bioassays on cotton cheesecloth. BioUD provided significantly greater overall mean percentage repellency than IR3535 for A. americanum and D. variabilis. BioUD was significantly more repellent than oil of lemon eucalyptus for A. americanum but did not differ significantly in repellency against D. variabilis. No statistically significant difference in overall mean percentage repellency was found between BioUD and DEET for A. americanum or D. variabilis. In a 7-week time course bioassay, BioUD applied to cotton cheesecloth and held at room temperature provided 5 weeks of > 90% repellency against A. americanum.}, number={4}, journal={AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE}, author={Bissinger, Brooke W. and Zhu, Jiwei and Apperson, Charles S. and Sonenshine, Daniel E. and Watson, D. Wesley and Roe, R. Michael}, year={2009}, month={Oct}, pages={685–690} } @article{bissinger_apperson_sonenshine_watson_roe_2009, title={Efficacy of the new repellent BioUD(A (R)) against three species of ixodid ticks}, volume={48}, ISSN={["1572-9702"]}, DOI={10.1007/s10493-008-9235-x}, abstractNote={BioUD ® with the active ingredient 2-undecanone originally derived from wild tomato plants is a new repellent recently registered by the US EPA. Repellent efficacy of BioUD ® (7.75% 2-undecanone) and DEET (98.11%) was examined in the laboratory using a choice test between repellent-treated and control filter paper surfaces for Amblyomma americanum, Dermacentor variabilis, and Ixodes scapularis. BioUD ® provided greater repellency against A. americanum and I. scapularis than DEET. No difference was found between BioUD ® and DEET against D. variabilis. In head-to-head assays between BioUD ® and DEET, undiluted and 50% dilutions of BioUD® were more repellent than undiluted DEET against all three species tested. Similarly, a 25% dilution of BioUD® was more repellent than DEET against A. americanum while no difference in mean percentage repellency was found between a 25% dilution of BioUD® and DEET against I. scapularis. Based on regression analysis, the concentration of BioUD® required for equivalent repellency to 98.11% DEET was 39.5% for D. variabilis and 29.7% for I. scapularis. A log-probit model could not be constructed for A. americanum from the dosages tested. Based on filter paper head-to-head assays, BioUD® is at least 2–4 times more active as a repellent than DEET against three species of ixodid ticks under the conditions of our laboratory bioassays.}, number={3}, journal={EXPERIMENTAL AND APPLIED ACAROLOGY}, author={Bissinger, B. W. and Apperson, C. S. and Sonenshine, D. E. and Watson, D. W. and Roe, R. M.}, year={2009}, month={Jul}, pages={239–250} } @article{ocampo_gonzalez_morales_perez_wesson_apperson_2009, title={Evaluation of community-based strategies for Aedes aegypti control inside houses}, volume={29}, ISSN={["0120-4157"]}, DOI={10.7705/biomedica.v29i2.30}, abstractNote={Dengue viruses transmitted principally by the urban mosquito Aedes aegypti, cause one of the major public health problems confronting tropical cities. Insecticide spraying has been the mainstay of mosquito control; however, its continuous use has selected for resistance. Other important methods of control involve community participation.This study evaluated two control methods for Ae. aegypti that can be used by the community: Lethal ovitraps (LOs) and Bacillus thuringiensis var israeliensis (Bti) briquettes.The project study was carried out in four similar neighborhoods within a representative district in the city of Cali, Colombia. Three interventions (LO, Bti, LO+Bti plus education and one control (education only) area were evaluated for efficacy in post-intervention entomological surveys. Additionally, entomological indices were also compared to results from a pre-intervention survey carried out on a sample of city blocks in the same neighborhoods. Relative vector abundance in relation to weather conditions using the same entomological sampling methods was compared.The interventions did not achieve significant differences in vector abundance among the treatments. However, the interventions achieved a significant reduction in entomological indices compared with those observed during the pre-intervention survey: House index 15.1% vs. 8.5%, mean pupae per house 1.15 vs. 0.073, and Adult index 56.3% vs. 34.8% (p < 0.05).The lack of significant differences among the interventions, and between treated and control blocks suggested that educational activities together with periodic visits to the houses produced similar reductions of immature and adult Aedes aegypti.}, number={2}, journal={BIOMEDICA}, author={Ocampo, Clara B. and Gonzalez, Camila and Morales, Carlos A. and Perez, Mauricio and Wesson, Dawn and Apperson, Charles S.}, year={2009}, month={Jun}, pages={282–297} } @article{nojima_apperson_schal_2008, title={A simple, convenient, and efficient preparative GC system that uses a short megabore capillary column as a trap}, volume={34}, ISSN={["0098-0331"]}, DOI={10.1007/s10886-008-9437-z}, abstractNote={A simple, convenient, and highly efficient preparative GC system has been developed that uses short sections of megabore capillary columns as sample collection (sorbent) traps. The performance of this system with various types of capillary column traps and under various collection conditions was systematically investigated with model compounds, including C4 to C20 normal alkanes, esters, and alcohols. The thickness and polarity of the sorptive stationary phase and the temperature of the collection trap affected trap performance. Each group of compounds was efficiently trapped above a critical Kovat's index, and the type of trap (deactivated, methyl polysiloxane, polyethylene glycol), film thickness, and whether or not the trap was cooled significantly shifted this threshold index. Above this critical index, recovery efficiencies of traps with methyl polysiloxane films were 80-100% for a wide range of injected sample mass. For example, a DB-1 collection trap with a film thickness of 1.5 microm methyl polysiloxane operated at ambient temperature trapped >84% of the mass of injected compounds of all three chemical classes with Kovat's index >1,100 (determined on a nonpolar column) with injected sample mass ranging from 10 to 1,000 ng of each compound. This preparative GC system is technically and economically feasible for most researchers. Furthermore, it is suitable for the preparation of NMR samples of volatile and semivolatile compounds, especially with sample sizes ranging from several nanograms to several micrograms.}, number={3}, journal={JOURNAL OF CHEMICAL ECOLOGY}, author={Nojima, Satoshi and Apperson, Charles S. and Schal, Coby}, year={2008}, month={Mar}, pages={418–428} } @article{ponnusamy_xu_stav_wesson_schal_apperson_2008, title={Diversity of Bacterial Communities in Container Habitats of Mosquitoes}, volume={56}, ISSN={["1432-184X"]}, url={http://dx.doi.org/10.1007/s00248-008-9379-6}, DOI={10.1007/s00248-008-9379-6}, abstractNote={We investigated the bacterial diversity of microbial communities in water-filled, human-made and natural container habitats of the mosquitoes Aedes aegypti and Aedes albopictus in suburban landscapes of New Orleans, Louisiana in 2003. We collected water samples from three classes of containers, including tires (n = 12), cemetery urns (n = 23), and miscellaneous containers that included two tree holes (n = 19). Total genomic DNA was extracted from water samples, and 16S ribosomal DNA fragments (operational taxonomic units, OTUs) were amplified by PCR and separated by denaturing gradient gel electrophoresis (DGGE). The bacterial communities in containers represented diverse DGGE-DNA banding patterns that were not related to the class of container or to the local spatial distribution of containers. Mean richness and evenness of OTUs were highest in water samples from tires. Bacterial phylotypes were identified by comparative sequence analysis of 90 16S rDNA DGGE band amplicons. The majority of sequences were placed in five major taxa: Alpha-, Beta- and Gammaproteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, and an unclassified group; Proteobacteria and Bacteroidetes were the predominant heterotrophic bacteria in containers. The bacterial communities in human-made containers consisted mainly of undescribed species, and a phylogenetic analysis based on 16S rRNA sequences suggested that species composition was independent of both container type and the spatial distribution of containers. Comparative PCR-based, cultivation-independent rRNA surveys of microbial communities associated with mosquito habitats can provide significant insight into community organization and dynamics of bacterial species.}, number={4}, journal={MICROBIAL ECOLOGY}, author={Ponnusamy, Loganathan and Xu, Ning and Stav, Gil and Wesson, Dawn M. and Schal, Coby and Apperson, Charles S.}, year={2008}, month={Nov}, pages={593–603} } @article{ponnusamy_xu_nojima_wesson_schal_apperson_2008, title={Identification of bacteria and bacteria-associated chemical cues that mediate oviposition site preferences by Aedes aegypti}, volume={105}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.0802505105}, DOI={10.1073/pnas.0802505105}, abstractNote={The yellow fever mosquito,Aedes aegypti, the global vector of dengue and yellow fever, is inexorably linked to water-filled human-made containers for egg laying and production of progeny. Oviposition is stimulated by cues from water containers, but the nature and origin of these cues have not been elucidated. We showed that mosquito females directed most of their eggs to bamboo and white-oak leaf infusions, and only a small fraction of the eggs were laid in plain water containers. In binary choice assays, we demonstrated that microorganisms in leaf infusions produced oviposition-stimulating kairomones, and using a combination of bacterial culturing approaches, bioassay-guided fractionation of bacterial extracts, and chemical analyses, we now demonstrate that specific bacteria-associated carboxylic acids and methyl esters serve as potent oviposition stimulants for gravidAe. aegypti. Elucidation of these compounds will improve understanding of the chemical basis of egg laying behavior ofAe. aegypti, and the kairomones will likely enhance the efficacy of surveillance and control programs for this disease vector of substantial global public health importance.}, number={27}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Ponnusamy, L. and Xu, N. and Nojima, S. and Wesson, D. M. and Schal, C. and Apperson, C. S.}, year={2008}, month={Jul}, pages={9262–9267} } @article{richards_ghosh_zeichner_apperson_2008, title={Impact of source reduction on the spatial distribution of larvae and pupae of Aedes albopictus (Diptera : Culicidae) in suburban neighborhoods of a Piedmont community in North Carolina}, volume={45}, ISSN={["1938-2928"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-49249101341&partnerID=MN8TOARS}, DOI={10.1603/0022-2585(2008)45[617:IOSROT]2.0.CO;2}, abstractNote={Abstract Aedes albopictus (Skuse) is a principal nuisance mosquito species and a potential arbovirus vector throughout its geographic range in the United States. This species lays eggs, and progeny complete development in water-filled containers that are discarded in suburban landscapes. Source reduction of containers, achieved through environmental sanitation, was used to experimentally manipulate mosquito production to gain insight into the spatial structure of the population of immature Ae. albopictus. Our studies were conducted in suburban landscapes in Raleigh, NC, during the 2002 and 2003 mosquito seasons. Spatial analyses, using estimates of the mean and total standing crop of pupae and counts of the numbers of mosquito-positive containers, showed that the distribution of mosquito production was not spatially dependent on a neighborhood-wide basis. However, in all neighborhoods, mosquito production was clustered in at least one and often more than one adjacent residence. Point pattern analyses that considered only the presence or absence of pupae showed that pupae-positive residences were dispersed throughout neighborhoods receiving monthly source reduction treatments and clustered throughout control neighborhoods, indicating that source reduction affected the spatial distribution of pupae. Conversely, spatial analyses based on the presence or absence of larvae and pupae showed that mosquito production was randomly distributed among residences in both control and source reduction neighborhoods, showing that Ae. albopictus recolonized containers within several weeks after source reduction was implemented. Knowledge of the spatial distribution of production sites would allow management efforts for Ae. albopictus to be targeted to residences supporting high levels of mosquito production.}, number={4}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Richards, Stephanie L. and Ghosh, Sujit K. and Zeichner, Brian C. and Apperson, Charles S.}, year={2008}, month={Jul}, pages={617–628} } @article{witting-bissinger_stumpf_donohue_apperson_roe_2008, title={Novel arthropod repellent, BioUD, is an efficacious alternative to deet}, volume={45}, ISSN={["1938-2928"]}, DOI={10.1603/0022-2585(2008)45[891:NARBIA]2.0.CO;2}, abstractNote={Abstract For >50 yr, N,N-diethyl-3-methylbenzamide (deet) has been the standard for arthropod repellents and has been an important tool to protect people from disease agents carried by ticks, mosquitoes, and other arthropods. However, some people avoid using deet because of concerns about adverse health effects. In 2007, a new repellent, BioUD, with the active ingredient 7.75% 2-undecanone, originally derived from wild tomato (Lycopersicon hirsutum Dunal f. glabratum C. H. Müll) plants, was registered by the U.S. Environmental Protection Agency. In the current study, repellent efficacy of BioUD was compared using arm-in-cage studies with 7 and 15% deet against the mosquitoes Aedes aegypti (L.) and Aedes albopictus Skuse. No differences were found in mean repellency over 6 h after application between BioUD versus 7 and 15% deet for Ae albopictus. For Ae. aegypti, no differences were found over the same time period for 7% deet. Compared with 15% deet, BioUD mean repellency was lower over the 6-h test period. Human subject field trials were conducted in North Carolina, United States, and Ontario, Canada, comparing the repellency of BioUD to products containing 25 and 30% deet. BioUD provided the same repellency or was more efficacious than 25 and 30% deet, respectively, in these studies. Laboratory trials were conducted to determine the repellent activity of BioUD against the American dog tick, Dermacentor variabilis (Say), on human skin and cloth. BioUD repelled ticks at least 2.5 h after application to human skin. On cloth, no differences in mean repellency were found through 8 d after application between BioUD and 7% deet. In a two-choice test for BioUD versus 15% deet on filter paper, ticks spent significantly more time on the deet-treated surface than the BioUD-treated surface. Based on these studies in toto, BioUD is an efficacious alternative to deet in its repellent activity.}, number={5}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Witting-Bissinger, B. E. and Stumpf, C. F. and Donohue, K. V. and Apperson, C. S. and Roe, R. M.}, year={2008}, month={Sep}, pages={891–898} } @article{apperson_engber_nicholson_mead_engel_yabsley_dail_johnson_watson_2008, title={Tick-Borne Diseases in North Carolina: Is "Rickettsia amblyommii" a Possible Cause of Rickettsiosis Reported as Rocky Mountain Spotted Fever?}, volume={8}, ISSN={["1557-7759"]}, DOI={10.1089/vbz.2007.0271}, abstractNote={Cases of Rocky Mountain spotted fever (RMSF) in North Carolina have escalated markedly since 2000. In 2005, we identified a county in the Piedmont region with high case numbers of RMSF. We collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (SFGR) might be emerging. Amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. In contrast, Dermacentor variabilis, the American dog tick, a principal vector of Rickettsia rickettsii, comprised < 1% of the ticks collected. Eleven of 25 lone star tick pools tested were infected with "Rickettsia amblyommii," an informally named SFGR. Sera from patients from the same county who were presumptively diagnosed by local physicians with a tick-borne illness were tested by an indirect immunofluorescence antibody (IFA) assay to confirm clinical diagnoses. Three of six patients classified as probable RMSF cases demonstrated a fourfold or greater rise in IgG class antibody titers between paired acute and convalescent sera to "R. amblyommii" antigens, but not to R. rickettsii antigens. White-tailed deer, Odocoileus virginianus, are preferred hosts of lone star ticks. Blood samples collected from hunter-killed deer from the same county were tested by IFA test for antibodies to Ehrlichia chaffeensis and "R. amblyommii." Twenty-eight (87%) of 32 deer were positive for antibodies to E. chaffeensis, but only 1 (3%) of the deer exhibited antibodies to "R. amblyommii," suggesting that deer are not the source of "R. amblyommii" infection for lone star ticks. We propose that some cases of rickettsiosis reported as RMSF may have been caused by "R. amblyommii" transmitted through the bite of A. americanum.}, number={5}, journal={VECTOR-BORNE AND ZOONOTIC DISEASES}, author={Apperson, Charles S. and Engber, Barry and Nicholson, William L. and Mead, Daniel G. and Engel, Jeffrey and Yabsley, Michael J. and Dail, Kathy and Johnson, Joey and Watson, D. Wesley}, year={2008}, month={Oct}, pages={597–606} } @article{savage_aggarwal_apperson_katholi_gordon_hassan_anderson_charnetzky_mcmillen_unnasch_et al._2007, title={Host choice and West Nile virus infection rates in blood-fed mosquitoes, including members of the Culex pipiens complex, from Memphis and Shelby County, Tennessee, 2002-2003}, volume={7}, ISSN={["1557-7759"]}, DOI={10.1089/vbz.2006.0602}, abstractNote={The source of bloodmeals in 2,082 blood-fed mosquitoes collected from February 2002 through December 2003 in Memphis and surrounding areas of Shelby County, Tennessee were determined. Members of the genus Culex and Anopheles quadrimaculatus predominated in the collections. Members of the Cx. pipiens complex and Cx. restuans were found to feed predominately upon avian hosts, though mammalian hosts made up a substantial proportion of the bloodmeals in these species. No significant difference was seen in the host class of bloodmeals in mosquitoes identified as Cx. pipiens pipiens, Cx. p. quinquefasciatus, or hybrids between these two taxa. Anopheles quadrimaculatus and Cx. erraticus fed primarily upon mammalian hosts. Three avian species (the American Robin, the Common Grackle, and the Northern Cardinal) made up the majority of avian-derived bloodmeals, with the American Robin representing the most frequently fed upon avian host. An analysis of these host feeding data using a modification of a transmission model for Eastern Equine encephalitis virus suggested that the American Robin and Common Grackle represented the most important reservoir hosts for West Nile virus. A temporal analysis of the feeding patterns of the dominant Culex species did not support a shift in feeding behavior away from robins to mammals late in the summer. However, a significant degree of temporal variation was noted in the proportion of robin-derived bloodmeals when the data were analyzed by semi-monthly periods throughout the summers of 2002 and 2003. This pattern was consistent with the hypothesis that the mosquitoes were preferentially feeding upon nesting birds.}, number={3}, journal={VECTOR-BORNE AND ZOONOTIC DISEASES}, author={Savage, Harry M. and Aggarwal, Deepak and Apperson, Charles S. and Katholi, Charles R. and Gordon, Emily and Hassan, K. Hassan and Anderson, Michael and Charnetzky, Dawn and McMillen, Larry and Unnasch, Emily A. and et al.}, year={2007}, pages={365–386} } @article{hunt_apperson_kennedy_harrison_lord_2006, title={Occurrence and relative abundance of mosquitoes in stormwater retention facilities in North Carolina, USA}, volume={54}, ISSN={["1996-9732"]}, DOI={10.2166/wst.2006.625}, abstractNote={Throughout the 2004 mosquito season, 52 stormwater retention facilities were sampled to characterize the seasonal occurrence and relative abundance of mosquito species in relation to the structural complexity and biological diversity of the facilities. The three different types of facilities included standard wet ponds (n=20), innovative ponds (n=14), and wetland ponds (n=18). All retention structures were sampled at the beginning, middle and end of the mosquito season so that seasonal changes in mosquito production could be characterized. Overall samplings, mosquitoes were collected from 34% of the retention structures. Fourteen species representing 7 genera were collected, but only 5 species (Culex erraticus, Cx. territans, Anophelesquadrimaculatus, An. punctipennis and Uranotaenia sapphirina) were commonly collected in all three types of stormwater management facilities. In general, the seasonal prevalence and relative abundance of mosquito species did not vary among three types of retention structures. A significant association (P<0.01) between the presence of mosquito larvae or pupae and the absence of mosquitofish was found for innovative and wetland stormwater retention facilities but not for standard retention facilities (P>0.05).}, number={6-7}, journal={WATER SCIENCE AND TECHNOLOGY}, author={Hunt, W. F., III and Apperson, C. S. and Kennedy, S. G. and Harrison, B. A. and Lord, W. G.}, year={2006}, pages={315–321} } @article{richards_apperson_ghosh_cheshire_zeichner_2006, title={Spatial analysis of Aedes albopictus (Diptera : Culicidae) oviposition in suburban neighborhoods of a piedmont community in North Carolina}, volume={43}, ISSN={["0022-2585"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-33750941447&partnerID=MN8TOARS}, DOI={10.1603/0022-2585(2006)43[976:SAOAAD]2.0.CO;2}, abstractNote={Abstract Temporal and spatial distribution of egg-laying by Aedes albopictus (Skuse) (Diptera: Culicidae) was investigated in suburban neighborhoods in Raleigh, NC, by using oviposition traps (ovitraps) at fixed sampling stations during the 2002 and 2003 mosquito seasons. Variations in the phenology of oviposition between the two mosquito seasons resulted from differences in the patterns and amounts of rainfall early in the season. Aerial images of each study neighborhood were digitized, and the proportions of specific types of land cover within buffer zones encompassing ovitraps were estimated. Retrospective analyses showed that in some neighborhoods, oviposition intensity was significantly associated with specific types of land cover. However, in general, it seemed that gravid Ae. albopictus searched throughout the landscape for water-filled containers in which to lay eggs. Peridomestic surveys were carried out concurrently with ovitrap collections to estimate production of Ae. albopictus pupae in discarded water-filled containers and the abundance of females in vegetation that made up the resting habitat. Results of linear regression analyses indicated that the mean standing crop of pupae (total and per container) per residence was not a significant predictor of mean egg densities in ovitraps. However, the mean standing crop of adult females was a significant but weak predictor variable, because the magnitude and sign of regression coefficients varied between neighborhoods. Linear spatial regression analyses revealed that oviposition intensity was not spatially dependent on pupal standing crop or the numbers of pupae-positive containers distributed peridomestically. However, a weak spatial dependence on the standing crop of adult females was found in some neighborhoods. Based on spherical variogram models, kriging was carried out to predict the spatial patterns of oviposition in suburban neighborhoods. Focal areas of high and low oviposition intensity were evident in most neighborhoods; however, the spatial patterns of oviposition changed between mosquito seasons. Kriging predictions were evaluated, using cross-validation, by systematically removing each data point from our data set and predicting the removed point by using the remaining points. The root mean square (standardized) error values of best fitting variogram models approximated 1, and plots of standardized PRESS residuals showed no distinct pattern for most neighborhoods, indicating that predictions of the spatial distribution of oviposition intensity were valid. Spherical variogram models are a satisfactory method for describing the spatial distribution of Ae. albopictus oviposition, and kriging can be a useful technique for predicting oviposition intensity at locations that have not been sampled.}, number={5}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Richards, Stephanie L. and Apperson, Charles S. and Ghosh, Sujit K. and Cheshire, Heather M. and Zeichner, Brian C.}, year={2006}, month={Sep}, pages={976–989} } @article{thompson_khalil_jeffers_ananthapadmanaban_sonenshine_mitchell_osgood_apperson_roe_2005, title={In vivo role of 20-hydroxyecdysone in the regulation of the vitellogenin mRNA and egg development in the American dog tick, Dermacentor variabilis (Say)}, volume={51}, ISSN={["1879-1611"]}, DOI={10.1016/j.jinsphys.2005.05.011}, abstractNote={Injection of the hormone 20-hydroxyecdysone (20-E) into partially fed (virgin) female adults of the American dog tick, Dermacentor variabilis, while they are attached and feeding on the rabbit host, initiated the expression of the vitellogenin (Vg) gene, and Vg protein secretion and uptake by the ovary. The induction of egg production by 20-E in this bioassay was dose dependent in the range of 1–50 times the concentration normally found in a replete, vitellogenic female. Ticks examined 4 d after the 50× treatment were still attached to the host, had numerous enlarged vitellin-filled (brown) oocytes in their ovaries, but had not engorged to repletion. The ovaries reached weights similar to those found in untreated, replete (mated) females (pre-oviposition) while solvent-injected controls demonstrated no increase in oocyte size or increase in ovary weight. An increase in the levels of a putative Vg protein was observed in hemolymph samples collected 1, 2 and 3 d post-20-E injection but was not observed in the corresponding solvent controls as determined by native PAGE. Analysis of the ecdysteroid-induced protein by tryptic digestion-mass fingerprinting and BLASTP found that the putative Vg had the strongest match to GP80 (U49934), the partial sequence for the vitellogenin protein from Boophilus microplus. A partial Vg cDNA was cloned and sequenced from replete females of D. variabilis with a high similarity to GP80. Using this message as a probe, Northern blots conducted with RNA collected from partially fed, virgin females 1, 2 and 3 d post-20-E injection showed upregulation of the Vg mRNA on all 3 days. Controls injected with solvent only showed no Vg mRNA. Injections with juvenile hormone III did not stimulate Vg expression, oocyte growth or full engorgement. These studies indicate that ecdysteroids and not JH can initiate expression of the Vg gene, Vg protein synthesis and release into hemolymph, and Vg uptake into developing oocytes under bioassay conditions mimicking normal feeding on the host.}, number={10}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Thompson, DM and Khalil, SMS and Jeffers, LA and Ananthapadmanaban, U and Sonenshine, DE and Mitchell, RD and Osgood, CJ and Apperson, CS and Roe, RM}, year={2005}, month={Oct}, pages={1105–1116} } @article{utz_apperson_dietz_2005, title={Social impacts of La Crosse encephalitis, in North Carolina}, volume={64}, ISSN={["1938-3525"]}, DOI={10.17730/humo.64.2.xa6yqcmf13qnu2k9}, abstractNote={La Crosse (LAC) encephalitis, caused by a mosquito-transmitted virus, is endemic in the mountains of North Carolina and increasingly recognized in other areas of southern Appalachia. To obtain information on the social and familial impacts of LAC encephalitis in North Carolina, adult case patients (n = 2) and the parents/guardians of juvenile case patients (n = 23) were interviewed. Non-monetary quantitative and qualitative methods were used to estimate the burden of disease over the cumulative life years that elapsed from the onset of illness to the date of interviews. The largest portion of the psychological and social impact of LAC encephalitis was borne by case patients with lifelong neurological sequelae (the aftereffect of a disease or injury) (n = 5). Case patients (n = 16) manifesting transitory sequelae were impacted to a lesser extent, but signi?cantly greater (P < 0.05) than patients (n = 4) who recovered completely from the illness. Prior to a family member contracting the illness, 80% of study participants were unaware of LAC encephalitis; consequently, they were not concerned about the health impacts of the disease. Lack of public awareness appears to result in part because LAC encephalitis is presently is under-reported and under-recognized by the medical community. The disease burden imposed by LAC encephalitis could be reduced if the public health community would develop disease prevention education and engage in active case surveillance coupled with case reporting and follow-up assistance to families. The La Crosse encephalitis prevention program should be community-based, but include organization of a mosquito abatement agency staffed with professional mosquito biologists. The social impacts of LAC encephalitis are representative of effects expected from other neuroinvasive arboviral diseases, such as West Nile encephalitis, for which there are relatively fewer case patients in long-term recovery.}, number={2}, journal={HUMAN ORGANIZATION}, author={Utz, JT and Apperson, CS and Dietz, EJ}, year={2005}, pages={135–146} } @article{apperson_hassan_harrison_savage_aspen_farajollahi_crans_daniels_falco_benedict_et al._2004, title={Host feeding patterns of established and potential mosquito vectors of West Nile virus in the eastern United States}, volume={4}, ISSN={["1557-7759"]}, DOI={10.1089/153036604773083013}, abstractNote={An important variable in determining the vectorial capacity of mosquito species for arthropod-borne infections is the degree of contact of the vector and the vertebrate reservoir. This parameter can be estimated by examining the host-feeding habits of vectors. Serological and polymerase chain reaction based methods have been used to study the host-feedings patterns of 21 mosquito species from New York, New Jersey, and Tennessee, 19 of which previously have been found infected with West Nile virus. Mammalophilic mosquito species in New Jersey and New York fed primarily upon white-tailed deer, while those from Memphis, Tennessee, fed mainly upon domestic dogs. A total of 24 different avian host species were detected among the avian-derived blood meals. American Robin, Northern Cardinal, Northern Mockingbird, Tufted Titmouse, and Brown-headed Cowbird were common avian hosts, while blood meals derived from the American Crow were relatively rare. Although the majority of common host species were potentially among the most abundant birds at each location, the proportion of blood meals from the most commonly fed upon avian species was greater than was predicted based upon the likely abundance of these species alone. These findings suggest that vector species for West Nile virus may preferentially feed upon certain avian hosts.}, number={1}, journal={VECTOR-BORNE AND ZOONOTIC DISEASES}, author={Apperson, CS and Hassan, HK and Harrison, BA and Savage, HM and Aspen, SE and Farajollahi, A and Crans, W and Daniels, TJ and Falco, RC and Benedict, M and et al.}, year={2004}, pages={71–82} } @article{utz_apperson_maccormack_salyers_dietz_mcpherson_2003, title={Economic and social impacts of la crosse encephalitis in western North Carolina}, volume={69}, ISSN={["1476-1645"]}, DOI={10.4269/ajtmh.2003.69.509}, abstractNote={La Crosse encephalitis (LACE), a human illness caused by a mosquito-transmitted virus, is endemic in western North Carolina. To assess the economic and social impacts of the illness, 25 serologically confirmed LACE case patients and/or families were interviewed to obtain information on the economic costs and social burden of the disease. The total direct and indirect medical costs associated with LACE over 89.6 life years accumulated from the onset of illness to the date of interview for 24 patients with frank encephalitis totaled dollar 791,374 (range = dollar 7,521-175,586), with a mean +/- SD per patient cost of dollar 32,974 +/- dollar 34,793. The projected cost of a case with lifelong neurologic sequelae ranged from dollar 48,775 to dollar 3,090,798 (n = 5). For the 25 LACE patients, 55.15 (54.83%) of the 100.59 cumulative life years (CLYs) were impaired to some degree. Disability adjusted life years (DALYs) were calculated to measure the productive life years lost to LACE. Approximately 13.00 DALYs were accumulated over 100.59 CLYs of study. Projected DALYs for case patients (n = 5) with lifelong neurologic sequelae ranged from 12.90 to 72.37 DALYs. An Impact of La Crosse Encephalitis Survey (ILCES) was used to measure the social impact of LACE over time for case patients and their families. The ILCES scores demonstrated that the majority of the social burden of the illness is borne by the five patients with lifelong neurologic sequelae. The socioeconomic burden resulting from LACE is substantial, which highlights the importance of the illness in western North Carolina, as well as the need for active surveillance, reporting, and prevention programs for the infection.}, number={5}, journal={AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE}, author={Utz, JT and Apperson, CS and MacCormack, JN and Salyers, M and Dietz, EJ and McPherson, JT}, year={2003}, month={Nov}, pages={509–518} } @article{trexler_apperson_gemeno_perich_carlson_schal_2003, title={Field and laboratory evaluations of potential oviposition attractants for Aedes albopictus (Diptera: Culicidae)}, volume={19}, number={3}, journal={Journal of the American Mosquito Control Association}, author={Trexler, J. D. and Apperson, C. S. and Gemeno, C. and Perich, M. J. and Carlson, D. and Schal, C.}, year={2003}, month={Sep}, pages={228–234} } @article{chism_apperson_2003, title={Horizontal transfer of the insect growth regulator pyriproxyfen to larval microcosms by gravid Aedes albopictus and Ochlerotatus triseriatus mosquitoes in the laboratory}, volume={17}, ISSN={["1365-2915"]}, DOI={10.1046/j.1365-2915.2003.00433.x}, abstractNote={Abstract.  The insect growth regulator (IGR) pyriproxyfen is highly active against mosquitoes (Diptera: Culicidae). Through continuous emersion of large larvae (instars 3–4) the concentration causing 50% inhibition of adult emergence (EI50) was determined as 0.200 p.p.b. for Aedes albopictus (Skuse) and 3.5 to 7 times less for Ochlerotatus triseriatus (Say): IE50 0.0288 p.p.b.}, number={2}, journal={MEDICAL AND VETERINARY ENTOMOLOGY}, author={Chism, BD and Apperson, CS}, year={2003}, month={Jun}, pages={211–220} } @article{trexler_apperson_zurek_gemeno_schal_kaufman_walker_watson_wallace_2003, title={Role of bacteria in mediating the oviposition responses of Aedes albopictus (Diptera : Culicidae)}, volume={40}, ISSN={["0022-2585"]}, DOI={10.1603/0022-2585-40.6.841}, abstractNote={Abstract The responses of Aedes albopictus to sources of oviposition attractants and stimulants were evaluated with a behavioral bioassay in which females attracted to odorants emanating from water were trapped on screens coated with an adhesive. Gravid mosquitoes were attracted to volatiles from larval-rearing water and soil-contaminated cotton towels. Bacteria were isolated from these substrates and from an organic infusion made with oak leaves. Through fatty acid-methyl ester analyses, six bacterial isolates from larval-rearing water, two isolates from soil-contaminated cotton towels, and three isolates from oak leaf infusion were identified to species. The response of gravid mosquitoes to these isolates was also evaluated in behavioral bioassays. Water containing Psychrobacter immobilis (from larval-rearing water), Sphingobacterium multivorum (from soil-contaminated cotton towels), and an undetermined Bacillus species (from oak leaf infusion) elicited significantly higher oviposition than control water without bacteria. Only volatiles collected from larval rearing water elicited significant electroantennogram responses in females.}, number={6}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Trexler, JD and Apperson, CS and Zurek, L and Gemeno, C and Schal, C and Kaufman, M and Walker, E and Watson, DW and Wallace, L}, year={2003}, month={Nov}, pages={841–848} } @misc{gudderra_sonenshine_apperson_roe_2002, title={Hemolymph proteins in ticks}, volume={48}, ISSN={["1879-1611"]}, DOI={10.1016/S0022-1910(02)00050-1}, abstractNote={In comparison to insects and Crustacea, our knowledge of the predominant hemolymph proteins in ticks is minimal. The hemolymph protein most studied in ticks has been vitellogenin (Vg). Vg is synthesized by the tick fat body after female adults obtain a blood meal, is released into the hemolymph and is absorbed by developing oocytes as vitellin (Vn). Much of what we know about Vg is from studies of Vn. In general, the carbohydrate, lipid and amino acid composition is similar to insects except that in the tick, Vg contains heme, most likely from the digestion of host hemoglobin. In the American dog tick, Dermacentor variabilis, Vg is comprised of two native proteins and seven subunits on SDS-PAGE. Vg has been characterized in five tick species but the amino acid sequence is not yet available. Another predominant hemolymph protein, apparently a carrier protein (CP), has recently been studied in two tick species. This protein is found in the hemolymph of both male and females adults, in adult tissues outside of the hemolymph in some tick species, in coxal fluid of soft ticks and in whole body homogenates from eggs, larvae and nymphs. CP from the hard tick, D. variabilis, contains cholesterol, phospholipids, monoacylglycerides, triacylglycerides, free fatty acids, carbohydrate and heme. Under identical assay conditions, the analogous protein in the soft tick, Ornithodoros parkeri, did not contain heme. CP in the American dog tick consists of two subunits, one of which has 61% identity to the biliprotein, artemocyanin, from the fairy shrimp. CP is identical to a heme-lipoprotein (HeLp) from Boophilus microplus. The exact roles of CP and HeLp have not yet been fully determined, but they apparently are important in heme sequestration and as a storage depot for protein and lipid. Macroglobulin, lectin, antimicrobial, JH binding, JH esterase, and other tick hemolymph proteins are also discussed.}, number={3}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Gudderra, NP and Sonenshine, DE and Apperson, CS and Roe, RM}, year={2002}, month={Mar}, pages={269–278} } @article{apperson_harrison_unnasch_hassan_irby_savage_aspen_watson_rueda_engber_et al._2002, title={Host-feeding habits of Culex and other mosquitoes (Diptera : Culicidae) in the Borough of Queens in New York City, with characters and techniques for identification of Culex mosquitoes}, volume={39}, ISSN={["1938-2928"]}, DOI={10.1603/0022-2585-39.5.777}, abstractNote={Abstract The host-feeding patterns of mosquitoes (n = 247) collected in the Borough of Queens in New York City in July and August 2000 were investigated using an indirect ELISA and a polymerase chain reaction (PCR)-heteroduplex assay. Culex pipiens L. and Cx. restuans Theobald fed primarily on birds, and their feeding habits support their implication as enzootic vectors of West Nile virus. Culex salinarius Coquillett and Coquillettidia perturbans (Walker) fed mainly on mammals, with fewer blood meals taken from birds, and these two species are potential bridge vectors of West Nile virus. Culex mosquitoes took blood meals (n = 54) from 11 different avian species. Only the northern cardinal (Cardinalis cardinalis), American robin (Turdus migratorius), and Brown-headed cow bird (MolIothrus ater) were fed upon by all three Culex species. Multiple blood feedings on avian hosts were detected in Cx. pipiens and Cx. restuans. Species identifications of Culex mosquitoes made using morphological characteristics were confirmed with a PCR assay that employed species-specific primers. All Cx. pipiens (n = 20) and Cx. salinarius (n = 10) specimens were correctly identified, but three (20%) of 15 Cx. restuans were misidentified as Cx. pipiens.}, number={5}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Apperson, CS and Harrison, BA and Unnasch, TR and Hassan, HK and Irby, WS and Savage, HM and Aspen, SE and Watson, DW and Rueda, LM and Engber, BR and et al.}, year={2002}, month={Sep}, pages={777–785} } @article{apperson_2002, title={Kenneth Lee Knight.}, volume={48}, number={3}, journal={American Entomologist (Lanham, Md.)}, author={Apperson, C. S.}, year={2002}, pages={189–190} } @article{gudderra_sonenshine_apperson_roe_2002, title={Tissue distribution and characterization of predominant hemolymph carrier proteins from Dermacentor variabilis and Ornithodoros parkeri}, volume={48}, ISSN={["0022-1910"]}, DOI={10.1016/s0022-1910(01)00160-3}, abstractNote={The tissue distribution of the predominant hemolymph protein found throughout tick development was examined in the hard tick, Dermacentor variabilis, and in the soft tick, Ornithodoros parkeri. In D. variabilis, the predominant (purified) hemolymph protein was a lipoglycoheme-carrier protein (DvCP) with a molecular weight of 200 K. A protein with a similar mobility on native-PAGE was found in fat body, salivary gland, muscle and ovary from partially fed females which was most abundant in the plasma and salivary gland. DvCP from plasma, salivary gland and fat body of partially fed females consisted of two subunits on SDS-PAGE (98 and 92 K). In replete females, only salivary gland exhibited protein subunits equivalent to hemolymph CP. CP in salivary gland and fat body stained positive for lipids. The concentration of CP in tissues varied between partially fed and replete females, indicating a difference in the expression and/or sequestration of CP during adult development. The predominant hemolymph carrier protein from O. parkeri (OpCP) was purified to homogeneity for the first time and is presumed to have similar functions to CP from D. variabilis. Purified OpCP exhibited a molecular weight of 668 K by native-PAGE. Unlike CP from D. variabilis, OpCP was not detected in fat body or salivary gland tissues but occurred abundantly in coxal fluid. By SDS-PAGE, purified hemolymph OpCP consisted of two major subunits (114 and 93 K) and a less abundant protein with an apparent molecular weight of 48 K. Purified native OpCP was a lipoprotein like DvCP. A spectral analysis of purified OpCP failed to demonstrate the presence of heme like that found for CP from D. variabilis, purified by the same methods. However, plasma from O. parkeri contained heme with a λmax of 410 nm.}, number={2}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Gudderra, NP and Sonenshine, DE and Apperson, CS and Roe, RM}, year={2002}, month={Feb}, pages={161–170} } @article{nagayama_komar_levine_biggerstaff_apperson_2001, title={Bunyavirus infections in North Carolina white-tailed deer (Odocoileus virginianus)}, volume={1}, number={2}, journal={Vector Borne and Zoonotic Diseases (Larchmont, N.Y.)}, author={Nagayama, J. N. and Komar, N. and Levine, J. F. and Biggerstaff, B. and Apperson, C. S.}, year={2001}, pages={169–172} } @article{gudderra_neese_sonenshine_apperson_roe_2001, title={Developmental profile, isolation, and biochemical characterization of a novel lipoglycoheme-carrier protein from the American dog tick, Dermacentor variabilis (Acari : Ixodidae) and observations on a similar protein in the soft tick, Ornithodoros parkeri (Acari : Argasidae)}, volume={31}, ISSN={["0965-1748"]}, DOI={10.1016/s0965-1748(00)00122-3}, abstractNote={A novel lipoglycoheme-carrier protein (CP) in the American dog tick, Dermacentor variabilis (Say) has been purified and characterized. CP was purified by native–PAGE from partially fed virgin females. CP has a density of 1.25 g/ml with a molecular weight of 200 K by native–PAGE and 340 K by gel filtration chromatography. CP is comprised of two majour subunits, 98 K and 92 K in molecular weight by SDS–PAGE. Separate amino acid composition of the two subunits indicated high contents of As(x), Gl(x) and leucine. However, the N-terminal amino acid sequence of the two subunits was only 13% identical. The lower molecular weight subunit showed 61% identity to artemocyanin (biliprotein) in fairy shrimps, 46% identity to minor vitellogenin in chickens and 13% identity to vitellin of the black-legged tick. No similarity match was found for the other subunit. CP is a lipoglycoheme-protein as indicated by selective staining of native–PAGE gel for lipids, carbohydrates and heme. Lipid analysis by thin layer chromatography revealed the presence of cholesterol, phospholipids, monoacylglycerides, triacylglycerides and free fatty acids. Heme associated with purified CP demonstrated a λmax of 397.5 nm while the λmax of crude hemolymph plasma was 402.5 nm. The presence of CP in whole body homogenates of eggs, unfed and fed larvae and fed nymphs as well as in the plasma of unfed and fed adults including vitellogenic females was demonstrated by native–PAGE. Although a protein of analogous size was not found in the soft tick, Ornithodoros parkeri Cooley, a high molecular weight protein (500 K) is the predominant plasma protein in both unfed and fed male and female adults of that species as determined by native–PAGE. Also, CP appears to function as a biliprotein which sequesters heme.}, number={4-5}, journal={INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY}, author={Gudderra, NP and Neese, PA and Sonenshine, DE and Apperson, CS and Roe, RM}, year={2001}, month={Mar}, pages={299–311} } @article{gerhardt_gottfried_apperson_davis_erwin_smith_panella_powell_nasci_2001, title={First isolation of La Crosse virus from naturally infected Aedes albopictus}, volume={7}, DOI={10.3201/eid0705.010006}, abstractNote={La Crosse virus (LAC), a California serogroup bunyavirus, is the leading cause of pediatric arboviral encephalitis in the United States and an emerging disease in Tennessee, West Virginia, and North Carolina.Human cases of LAC encephalitis in Tennessee and North Carolina have increased above endemic levels during 1997 to 1999 and may represent an expansion of a new southeastern endemic focus.This report describes the isolation of LAC virus from the exotic mosquito Aedes albopictus.The discovery of LAC virus in wild populations of Ae. albopictus , coupled with its expanding distribution in the southeastern United States, suggests that this mosquito may become an important accessory vector, potentially increasing the number of human cases in endemic foci or expanding the range of the disease.}, number={5}, journal={Emerging Infectious Diseases}, author={Gerhardt, R. R. and Gottfried, K. L. and Apperson, C. S. and Davis, B. S. and Erwin, P. C. and Smith, A. B. and Panella, N. A. and Powell, E. E. and Nasci, R. S.}, year={2001}, pages={807–811} } @article{neese_sonenshine_kallapur_apperson_roe_2000, title={Absence of insect juvenile hormones in the American dog tick, Dermacentor variabilis (Say) (Acari : Ixodidae), and in Ornithodoros parkeri Cooley (Acari : Argasidae)}, volume={46}, ISSN={["0022-1910"]}, DOI={10.1016/S0022-1910(99)00134-1}, abstractNote={Synganglia, salivary gland, midgut, ovary, fat body and muscle alone and in combination from the ixodid tick, Dermacentor variabilis (Say), or the argasid tick, Ornithodoros parkeri Cooley, were incubated in vitro in separate experiments with L-[methyl-(3)H]methionine and farnesoic acid or with [1-(14)C]acetate. Life stages examined in D. variabilis were 3 and 72 h old (after ecdysis) unfed nymphs, partially fed nymphs (18 and 72 h after attachment to the host), fully engorged nymphs (2 d after detachment from host), 3 and 72 h old (after eclosion) unfed females, partially fed unmated females (12-168 h after attachment to host) and mated replete females (2 d after detachment from the host). Those from O. parkeri were third and fourth stadium nymphs and female O. parkeri, 1-2 d after detachment. Corpora allata from Diploptera punctata, Periplaneta americana and Gromphadorina portentosa were used as positive controls in these experiments. No farnesol, methyl farnesoate, JH I, JH II, JH III, or JHIII bisepoxide was detected by radio HPLC from any tick analysis while JH III, methyl farnesoate, and farnesol were detected in the positive controls. To examine further for the presence of a tick, insect-juvenilizing agent, Galleria pupal-cuticle bioassays were conducted on lipid extracts from 10 and 15 d old eggs, unfed larvae (1-5 d after ecdysis), unfed nymphs (1-7 d after ecdysis), and partially fed, unmated female adults (completed slow feeding phase) of D. variabilis. Whole body extracts of fourth stadium D. punctata and JH III standard were used as positive controls. No juvenilizing activity in any of the tick extracts could be detected. Electron impact, gas chromatography-mass spectrometry of hemolymph extracts from fed, virgin (forcibly detached 7 d after attachment) and mated, replete (allowed to drop naturally) D. variabilis and fully engorged (1-2 d after detachment) O. parkeri females also failed to identify the common insect juvenile hormones. The same procedures were successful in the identification of JH III in hemolymph of fourth stadium D. punctata. Last stadium nymphal (female) O. parkeri implanted with synganglia from second nymphal instars underwent normal eclosion to the adult. The above studies in toto suggest that D. variabilis and O. parkeri do not have the ability to make the common insect juvenile hormones, and these juvenile hormones do not regulate tick metamorphosis or reproduction as hypothesized in the literature.}, number={4}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Neese, PA and Sonenshine, DE and Kallapur, VL and Apperson, CS and Roe, RM}, year={2000}, month={Apr}, pages={477–490} } @article{ryan_apperson_orndorff_levine_2000, title={Characterization of Lyme disease spirochetes isolated from ticks and vertebrates in North Carolina}, volume={36}, ISSN={["1943-3700"]}, DOI={10.7589/0090-3558-36.1.48}, abstractNote={Borrelia burgdorferi isolates obtained from numerous locations and from different hosts in North Carolina, were compared to previously characterized strains of the Lyme disease spirochete and other Borrelia spp. The spirochete isolates were confirmed to be B. burgdorferi sensu stricto based on immunofluorescence (IFA) using a monoclonal antibody to outer surface protein A (Osp A [H5332]) and polymerase chain reaction (PCR) using a species-specific nested primer for a conserved region of the gene that encodes for flagellin. In addition, the isolates tested positive in Western blots with species-specific monoclonal antibodies for outer surface protein A and OspB (84c), and the genus-specific, monoclonal antibody to flagellin (H9724). Infectivity studies with several of these isolates were conducted using Mus musculus and Oryzomys palustris and the isolates exhibited markedly different levels of infectivity. This study demonstrates that B. burgdorferi sensu stricto is present and naturally transmitted on the Outer Banks and in the Coastal Plain and Piedmont regions of North Carolina.}, number={1}, journal={JOURNAL OF WILDLIFE DISEASES}, author={Ryan, JR and Apperson, CS and Orndorff, PE and Levine, JF}, year={2000}, month={Jan}, pages={48–55} } @article{teng_apperson_2000, title={Development and survival of immature Aedes albopictus and Aedes triseriatus (Diptera : Culicidae) in the laboratory: Effects of density, food, and competition on response to temperature}, volume={37}, ISSN={["0022-2585"]}, DOI={10.1603/0022-2585-37.1.40}, abstractNote={Abstract Effects of food, density, and heterospecific interactions on temperature-dependent development of Aedes albopictus (Skuse) and Aedes triseriatus (Say) larvae and pupae were described using a degree-day model. Under all conditions, the predicted number of degree-days (DDT0) to complete larval development was less, and the threshold temperature (T0) for initiation of larval development was higher for Ae. albopictus than for Ae. triseriatus. The DDT0 for both species was food and density dependent. However, the per capita food ration appeared to exert a greater influence on the developmental times of Ae. triseriatus immatures, whereas for Ae. albopictus effects of density were not completely eliminated by an increase in the per capita food ration. The presence of heterospecific larvae did not prolong the DDT0 of either species. At the low food ration, DDT0 for both species were significantly greater under conspecific conditions. The DDT0 for Ae. triseriatus increased directly as the proportion of conspecific larvae increased. However, when a higher per capita food ration was provided, conspecific effects on DDT0 were mitigated. For Ae. albopictus, estimated DDT0 values for larvae reared in pure culture were significantly higher than when heterospecific larvae were present, regardless of the per capita amount of food provided. Survivorship of immatures was density and food-dependent for both species. Ae. albopictus exhibited higher immature survivorship under all conditions relative to Ae. triseriatus. For both species, survival probabilities were lowest under conditions of high density and low food. Addition of food improved survival for both species. The presence of heterospecific larvae exerted a differential effect on the survivorship response of Ae. albopictus immatures to temperature. Lowest probability of survival for Ae. albopictus was occurred at low temperature when the proportion of heterospecific larvae in containers was the highest. In contrast, at high temperatures, survivorship of immatures improved, but was lowest for pure species cultures. For Ae. triseriatus, survivorship of immatures was consistently lower for pure species cultures regardless of the temperature. Standing crop production of adults of both species was primarily food rather that density-dependent. Under field conditions, Ae. triseriatus were predicted to initiate development sooner and exhibit faster population growth early in the season than Ae. albopictus. However, because of the shorter DDT0, Ae. albopictus population growth was predicted to surpass that of Ae. triseriatus populations later in the season. Based on optimal DDT0 values from laboratory experiments, spring emergence dates of Ae. triseriatus females in western North Carolina for 1989 and 1990 were predicted from accumulated degree-days calculated from local air temperature records. Predicted emergence dates were congruent with results of a previous survey for the same locality, indicating that accumulated degree-days can be used to accurately predict the seasonal occurrence of Ae. triseriatus. The utility of the degree-day approach in predicting the phenology of Ae. albopictus remains to be established.}, number={1}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Teng, HJ and Apperson, CS}, year={2000}, month={Jan}, pages={40–52} } @article{ryan_levine_apperson_lubke_wirtz_spears_orndorff_1998, title={An experimental chain of infection reveals that distinct Borrelia burgdorferi populations are selected in arthropod and mammalian hosts}, volume={30}, ISSN={["1365-2958"]}, DOI={10.1046/j.1365-2958.1998.01071.x}, abstractNote={The prokaryotic, spirochaetal microorganism Borrelia burgdorferi is the causative agent of Lyme disease, an arthropod‐borne disease of a variety of vertebrates and the most prevalent arthropod‐borne disease of humans in the United States. In order to understand better the normal life cycle of B. burgdorferi, an experimental chain of infection was devised that involved multiple sequential arthropod and mammalian passages. By examining populations of B. burgdorferi emerging from different points in this infectious chain, we demonstrate that selection of B. burgdorferi populations peculiar to arthropod or vertebrate hosts is a property of at least one of the two ecologically distinct strains we examined. Distinct B. burgdorferi populations were identified using an antigenic profile, defined by a set of monoclonal antibodies to eight B. burgdorferi antigens, and a plasmid profile, defined by the naturally occurring plasmids in the starting clonal populations. These two profiles constituted the phenotypical signature of the population. In the strain exhibiting selection in the different hosts, transition from one host to another produced a striking series of alternating phenotypical signatures down the chain of infection. At the molecular level, the alternating signatures were manifested as a reciprocal relationship between the expression of certain antigenic forms of outer surface protein (Osp) B and OspC. In the case of OspC, the antigenic changes could be correlated to the presence of one of two distinctly different alleles of the ospC gene in a full‐length and presumably transcriptionally active state. In the case of OspB, two alleles were again identified. However, their differences were minor and their relationship to OspB antigenic variation more complicated. In addition to the reciprocating changes in the antigenic profile, a reciprocating change in the size (probably the multimeric state) of a 9.0 kbp supercoiled plasmid was also noted. Selection of distinct populations in the tick may be responsible for the microorganism's ability to infect a wide range of vertebrate hosts efficiently, in that the tick might provide selective pressure for the elimination of the population selected in the previous host.}, number={2}, journal={MOLECULAR MICROBIOLOGY}, author={Ryan, JR and Levine, JF and Apperson, CS and Lubke, L and Wirtz, RA and Spears, PA and Orndorff, PE}, year={1998}, month={Oct}, pages={365–379} } @article{trexler_apperson_schal_1998, title={Laboratory and field evaluations of Oviposition responses of Aedes albopictus and Aedes triseriatus (Diptera : Culicidae) to oak leaf infusions}, volume={35}, ISSN={["0022-2585"]}, DOI={10.1093/jmedent/35.6.967}, abstractNote={Organic infusions created by fermenting white oak (Quercus alba L.) leaves in water were evaluated as sources of attractant odorants and contact oviposition stimulants for gravid Aedes albopictus (Skuse) and Aedes triseriatus (Say). Infusions were bioassayed in the laboratory by giving single females a choice of ovipositing in 1 container with infusion and 7 containers with water. Ae. albopictus laid significantly more eggs in containers with infusion, regardless of concentration (dilutions ranging from 10 to 100%) or age (fermentation periods of 7, 28, 60 d), than in containers holding water. The largest proportion of eggs (76.8%) was deposited in response to a 60% concentration of 7-d-old infusion. In contrast, Ae. triseriatus exhibited variable oviposition responses but generally deposited the largest number of eggs in only a few concentrations of older age infusions. In binary "sticky screen" bioassays, there was no difference between the numbers of females attracted to infusion or water, indicating that oviposition responses to infusion were mediated by contact chemostimulants rather than by attraction to odorants. Oviposition responses to infusions by field populations of Ae. albopictus and Ae. triseriatus in Raleigh, NC, were evaluated with pairs of oviposition traps, one containing infusion and the other containing water. Generally, Ae. albopictus laid significantly more eggs in ovitraps containing infusion regardless of its age (7, 28, and 60 d old) or the mass of leaves fermented (126 g = 1x or 504 g = 4x) than in water. In contrast, Ae. triseriatus deposited an equivalent number of eggs in traps containing water or 1x, 80% infusion regardless of its age; however, the oviposition response to ovitraps containing 4x, 7-d-old, 50% infusion was significant. Placement of an automobile tire behind an ovitrap did not increase the number of Ae. albopictus eggs laid in ovitraps containing 4x, 7-d-old, 50% infusion or water relative to ovitraps without a tire. Our research indicates that baiting ovitraps with oak leaf infusion would increase the sensitivity of surveillance efforts for Ae. albopictus and Ae. triseriatus.}, number={6}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Trexler, JD and Apperson, CS and Schal, C}, year={1998}, month={Nov}, pages={967–976} } @article{trexler_apperson_schal_1997, title={Diel oviposition patterns of Aedes albopictus (Skuse) and Aedes triseriatus (Say) in the laboratory and the field}, volume={22}, number={1}, journal={Journal of Vector Ecology}, author={Trexler, J. D. and Apperson, C. S. and Schal, C.}, year={1997}, pages={64–70} } @article{levine_apperson_howard_washburn_braswell_1997, title={Lizards as Hosts for Immature Ixodes scapularis (Acari: Ixodidae) in North Carolina}, volume={34}, ISSN={1938-2928 0022-2585}, url={http://dx.doi.org/10.1093/jmedent/34.6.594}, DOI={10.1093/jmedent/34.6.594}, abstractNote={Previously archived museum specimens of lizards collected throughout North Carolina were examined for Ixodes scapularis (Say). Lizards (n = 1,349) collected in 80 of North Carolina's 100 counties were examined. Lizards with ticks were collected in 23 (29%) of the 80 counties from which lizards were examined. I. scapularis was detected on 8.7% (n = 117) of the lizards and was the sole species of tick obtained from lizards. Immature ticks were most frequently found on the southeastern five-lined skink, Eumeces inexpectatus, and the eastern glass lizard, Ophisaurus ventralis. Larvae were most frequently found on the six-lined racerunner, Cnemidophorus sexlineatus. One C. sexlineatus harbored 177 larvae and 2 nymphs. Nymphs were most frequently observed on E. inexpectatus. The majority of counties (chi 2, P < 0.01) where ticks were found on lizards were in the Coastal Plain.}, number={6}, journal={Journal of Medical Entomology}, publisher={Oxford University Press (OUP)}, author={Levine, Jay F. and Apperson, Charles S. and Howard, Peter and Washburn, Michelle and Braswell, Alvin L.}, year={1997}, month={Nov}, pages={594–598} } @article{ouellette_apperson_howard_evans_levine_1997, title={Tick-raccoon associations and the potential for Lyme disease spirochete transmission in the coastal plain of North Carolina}, volume={33}, ISSN={["1943-3700"]}, DOI={10.7589/0090-3558-33.1.28}, abstractNote={Raccoons (Procyon lotor) were live-trapped and examined for ticks from July 1990 to July 1993 in the coastal plain of North Carolina on Marine Corps Base, Camp Lejeune, North Carolina (USA). Five species of ixodid ticks were found on 351 (78%) of 449 raccoons. Amblyomma americanum was the most abundant tick found on raccoons. Dermacentor variabilis, Ixodes texanus, and Ixodes scapularis were frequently collected, while Ixodes cookei were rarely collected from raccoons. Tick burdens were not affected by the age, sex, or trap location of captured raccoons. Ticks parasitizing raccoons had varying seasonal patterns of abundance. Amblyomma americanum were generally collected from raccoons year around, but infestation intensities were greatest in summer from June to September. Dermacentor variabilis adults were most abundant in mid-summer while peak numbers of larvae were collected in the fall. Infestation intensities of Ixodes texanus larvae were greatest in fall and winter months while nymphs were most abundant in winter and spring. No males were collected from raccoons, but females were most frequently collected in the spring and declined in abundance in the summer with no specimens collected in the fall or winter. Numbers of I. scapularis adults appeared to reach peak numbers in the fall while larvae and nymphs were most abundant on raccoons in winter. Spirochetes, Borrelia burgdorferi, were identified in a small percentage (0.2%) of host-seeking A. americanum nymphs and adults, and I. scapularis adults by immunofluorescent antibody assays. Similarly, a small percentage (1.9%) of host-associated A. americanum, D. variabilis, I. texanus and I. cookei contained B. burgdorferi. Borrelia burgdorferi spirochetes were cultured from the blood of 23 (26%) of 87 raccoons.}, number={1}, journal={JOURNAL OF WILDLIFE DISEASES}, author={Ouellette, J and Apperson, CS and Howard, P and Evans, TL and Levine, JF}, year={1997}, month={Jan}, pages={28–39} } @article{harrison_engber_apperson_1997, title={Ticks (Acari, Ixodida) uncommonly found biting humans in North Carolina}, volume={22}, number={1}, journal={Journal of Vector Ecology}, author={Harrison, B. A. and Engber, B. R. and Apperson, C. S.}, year={1997}, pages={6–12} } @article{levin_yang_apperson_levine_howard_1996, title={Reservoir Competence of the Southeastern Five-Lined Skink (Eumeces inexpectatus) and the Green Anole (Anolis carolinensis) for Borrelia burgdorferi}, volume={54}, ISSN={0002-9637 1476-1645}, url={http://dx.doi.org/10.4269/ajtmh.1996.54.92}, DOI={10.4269/ajtmh.1996.54.92}, abstractNote={The reservoir competence of two lizard species, the southeastern five-lined skink (Eumeces inexpectatus) and the green anole (Anolis carolinesis), for Borrelia burgdorferi was evaluated. Skinks and anoles were exposed by needle inoculation or tick bite to B. burgdorferi. Xenodiagnosis with larval Ixodes scapularis and culture of tissues were used to asses infection and the ability of infected lizards to infect attached ticks. Both lizard species were susceptible to B. burgdorferi by both routes of exposure. Xenodiagnostic ticks acquired spirochetes while feeding on both species. One tick that dropped from a skink on the ninth day after exposure was infected. The remainder of xenodiagnostic ticks that acquired spirochetes fed three weeks after exposure of the lizards to the spirochete. Lizards remained infectious to attached ticks for at least five weeks. Overall, more than 20% of xenodiagnostic larvae fed on southeastern five-lined skinks acquired spirochetes. Individual skinks infected up to 34% of attached ticks. A smaller proportion of ticks feeding on green anoles became infected. Borrelia burgdorferi recovered from infected lizards retained their infectivity for mammalian hosts. The ability of the lizards to sustain a Borrelia infection and infect attached ticks suggests that they may play a role in the maintenance of spirochete transmission.}, number={1}, journal={The American Journal of Tropical Medicine and Hygiene}, publisher={American Society of Tropical Medicine and Hygiene}, author={Levin, Michael and Yang, Sam and Apperson, Charles S. and Levine, Jay F. and Howard, Peter}, year={1996}, month={Jan}, pages={92–97} } @article{norris_levine_menard_nagagaki_howard_apperson_1996, title={Reservoir competence of raccoons (Procyon lotor) for Borrelia burgdorferi}, volume={32}, journal={Journal of Wildlife Diseases}, author={Norris, D. E. and Levine, J. F. and Menard, M. and Nagagaki, K. and Howard, P. and Apperson, C. S.}, year={1996}, pages={300–314} } @article{apperson_levine_evans_braswell_heller_1993, title={Relative utilization of reptiles and rodents as hosts by immature Ixodes scapularis (Acari: Ixodidae) in the coastal plain of North Carolina, USA}, volume={17}, number={10}, journal={Experimental & Applied Acarology}, author={Apperson, C. S. and Levine, J. F. and Evans, T. L. and Braswell, A. and Heller, J.}, year={1993}, pages={719–731} } @article{apperson_federici_tarver_stewart_1992, title={BIOTIC AND ABIOTIC PARAMETERS ASSOCIATED WITH AN EPIZOOTIC OF COELOMOMYCES-PUNCTATUS IN A LARVAL POPULATION OF THE MOSQUITO ANOPHELES-QUADRIMACULATUS}, volume={60}, ISSN={["1096-0805"]}, DOI={10.1016/0022-2011(92)90002-L}, abstractNote={Biotic and abiotic parameters associated with an epizootic of the fungus Coelomomyces punctatus in larval populations of the mosquito Anopheles quadrimaculatus were investigated for three mosquito breeding seasons (1986-1988) in two adjacent farm ponds in North Carolina. In the first pond, the prevalence of infected larvae averaged 42% (range 0-85%) for collections made weekly from May 1 to November 20, 1986, but larvae did not occur in this pond in 1987. Infection rates in the adjacent pond, sampled during the mosquito breeding seasons of 1987 and 1988, declined from 10.9% (range 0-27.5%) in 1987 to 2.5% (range 0-14.2%) in 1988. Correlation analyses between the number of female copepods and fungal infection rates in sentinel mosquitoes were significant (P < 0.01) for Acanthocyclops robustus but insignificant for eight other species. Infections obtained in sentinel larvae placed in the ponds for 3 hr intervals indicated that C. punctatus infected larvae around sundown. Infection rates for field-collected larvae increased with the stage of larval development. However, experiments with sentinel larvae showed that early instars were more susceptible to infection than later instars, suggesting that the higher infection rates in late instars resulted from individual larvae being infected by two or more zygotes during larval development. Standard multiple regression analyses, used to determine the relationship between seasonal infection rates and water chemistry, weather variables, and the abundance of early and late instar larvae, showed that the abundance of late instars was the only independent variable common to linear models. The models only accounted for 20 and 9% of the variation in larval infection rates for 1987 and 1988, respectively. These results indicate that of the parameters examined, the seasonal abundance of the copepod, A. robustus, was the most important factor (or variable) correlated with the prevalence of mosquito infection.}, number={3}, journal={JOURNAL OF INVERTEBRATE PATHOLOGY}, author={APPERSON, CS and FEDERICI, BA and TARVER, FR and STEWART, W}, year={1992}, month={Nov}, pages={219–228} } @article{apperson_federici_stewart_tarver_1992, title={EVIDENCE FOR THE COPEPODS ACANTHOCYCLOPS-ROBUSTUS AND MESOCYCLOPS-EDAX AS COMPETENT INTERMEDIATE HOSTS FOR COELOMOMYCES-PUNCTATUS DURING AN EPIZOOTIC IN A LARVAL POPULATION OF THE MOSQUITO ANOPHELES-QUADRIMACULATUS}, volume={60}, ISSN={["1096-0805"]}, DOI={10.1016/0022-2011(92)90003-M}, abstractNote={Field and laboratory experiments were conducted during an epizootic of Coelomomyces punctatus (Chytridiomycetes: Blastocladiales) in a population of the mosquito Anopheles quadrimaculatus in a North Carolina farm pond to examine the interactions of several potential copepod hosts with the mosquito and fungus. The diel vertical migratory behavior of the copepod species Acanthocyclops robustus, Eucyclops serrulatus, Macrocyclops albidus, and Mesocyclops edax were monitored in relation to infection rates in sentinel mosquito larvae. Mosquito infection occurred primarily around dusk, the same period during which A. robustus and E. serrulatus were most abundant near the surface of the pond. However, exposure of A. robustus, E. serrulatus, M. albidus, M. edax, Microcyclops varicans, and Paracyclops poppei to fungal meiospores in the laboratory showed that only A. robustus and M. edax were competent intermediate hosts for C. punctatus. Laboratory studies of the diel periodicity of gametangial dehiscence in A. robustus and M. edax infected with C. punctatus revealed that gamete release and zygote formation also occurred around dusk. The combined results of the laboratory and field studies on copepod abundance, susceptibility to infection, and periodicity of gametangial dehiscence suggest that A. robustus was the principal intermediate host for C. punctatus during the epizootic, though it is probable that M. edax also contributed importantly to the overall rate of larval infection.}, number={3}, journal={JOURNAL OF INVERTEBRATE PATHOLOGY}, author={APPERSON, CS and FEDERICI, BA and STEWART, W and TARVER, FR}, year={1992}, month={Nov}, pages={229–236} } @article{apperson_lanzaro_1991, title={Comparison of host-feeding patterns between Anopheles quadrimaculatus sibling species A and B}, volume={7}, number={3}, journal={Journal of the American Mosquito Control Association}, author={Apperson, C. S. and Lanzaro, G. C.}, year={1991}, pages={507} } @article{apperson_levine_nicholson_1990, title={Geographic Occurrence of Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae) Infesting White-tailed Deer in North Carolina}, volume={26}, ISSN={0090-3558}, url={http://dx.doi.org/10.7589/0090-3558-26.4.550}, DOI={10.7589/0090-3558-26.4.550}, abstractNote={A state-wide survey to determine the occurrence and comparative numbers of ticks infecting white-tailed deer (Odocoileus virginianus) was conducted in North Carolina (USA). One thousand six hundred twenty nine deer were examined in 60 of 100 counties; with the exception of one county in the piedmont region, all tick-infested deer occurred in the coastal plain. Ixodes scapularis (46%) and Amblyomma americanum (53%) were the most prevalent species encountered and accounted for more than 98% of the 4,286 ticks collected. Some specimens of Dermacentor albipictus and Amblyomma maculatum also were collected.}, number={4}, journal={Journal of Wildlife Diseases}, publisher={Wildlife Disease Association}, author={Apperson, Charles S. and Levine, Jay F. and Nicholson, William L.}, year={1990}, month={Oct}, pages={550–553} } @article{apperson_engber_levine_1989, title={Relative suitability of Aedes albopictus and Aedes aegypti in North Carolina to support development of Dirofilaria immitis}, volume={5}, number={3}, journal={Journal of the American Mosquito Control Association}, author={Apperson, C. S. and Engber, B. and Levine, J. F.}, year={1989}, pages={377–382} } @article{burt_hill_london_levine_1987, title={Magnetic resonance studies on the noncyclic phosphodiesters and other lipid related metabolites}, volume={1}, journal={FAEEB}, author={Burt, C. T. and Hill, C. H. and London, R. E. and Levine, J. F.}, year={1987}, pages={22–31} } @article{apperson_leidy_powell_1984, title={EFFECTS OF AMDRO ON THE RED IMPORTED FIRE ANT (HYMENOPTERA, FORMICIDAE) AND SOME NONTARGET ANT SPECIES AND PERSISTENCE OF AMDRO ON A PASTURE HABITAT IN NORTH-CAROLINA}, volume={77}, ISSN={["0022-0493"]}, DOI={10.1093/jee/77.4.1012}, abstractNote={A bait, Amdro, containing the toxicant AC217,300 (tetrahydro-5,5-dimethyl-2(1- H )-pyrimidinone[3-[4-(trifluoromethyl)phenyl]-1-[2-[4-(trifluoromethyl)phenyl]ethenyl]-2-propenylidene]hydrazone), was tested for efficacy against the red imported fire ant, Solenopsis invicta Buren, in a pasture in southeastern North Carolina. Significant ( P ≤ 0.05) differences in fire ant colony activity and structure were found between treatment and control populations following broadcast (1.7 kg [AI]/ha) and single mound (5 tablespoons per mound) applications. High numbers of incipient fire ant colonies were found in the treated areas of the pasture following the Amdro applications. Deleterious effects on nontarget ant species were not detected. Residues of Amdro were undetectable within 24 h of the broadcast application. Because of the rapid reoccupation of treated areas by incipient colonies, multiple applications of Amdro will be required to achieve long-term suppression of S. invicta populations.}, number={4}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={APPERSON, CS and LEIDY, RB and POWELL, EE}, year={1984}, pages={1012–1018} } @article{apperson_powell_browne_1984, title={Efficacy of individual mound treatments of MK-936 and Amdro against the red imported fire ant (Hymenoptera: Formicidae)}, volume={19}, number={4}, journal={Journal of the Georgia Entomological Society}, author={Apperson, C. S. and Powell, E. E. and Browne, M.}, year={1984}, pages={508} } @article{apperson_powell_1984, title={FORAGING ACTIVITY OF ANTS (HYMENOPTERA, FORMICIDAE) IN A PASTURE INHABITED BY THE RED IMPORTED FIRE ANT}, volume={67}, ISSN={["0015-4040"]}, DOI={10.2307/3494717}, abstractNote={The foraging activity of ants in a pasture inhabited by Solenopsis invicta Buren was investigated using pitfall traps and attractive baits. S. invicta and Lasius neoniger (Emery) were the most abundant and frequently collected species of ants. Correlation and multiple covariance analyses indicate that S. invicta is negatively associated with L. neoniger. Ant species were found to have localized population distributions that overlap slightly. S. invicta appeared to have a slight impact (0.1 > P > 0.05) on the number of ant species that occurred in the pasture.}, number={3}, journal={FLORIDA ENTOMOLOGIST}, author={APPERSON, CS and POWELL, EE}, year={1984}, pages={383–393} } @article{apperson_adams_1983, title={MEDICAL AND AGRICULTURAL IMPORTANCE OF RED IMPORTED FIRE ANT}, volume={66}, ISSN={["1938-5102"]}, DOI={10.2307/3494558}, abstractNote={Labauchena daguerri. Proc. Tall Timbers Conf. Ecol. Anim. Control Habitat Manage. 4: 41-52. STEIGER, U., U. E. LAMPARTET, C. SANDRI, AND K. AKERT. 1969. Virusahnliche partikel im Zytoplasma von Nerven und Gliazellen der Waldameise Arch. Gesante Virusforsch. 26: 271-82. SUMMERLIN, J. W. 1978. Beetles of the genera Myrmecophodius, Rhyssemus, and Blapstinus in Texas fire ant nests. Southwest. Ent. 3: 37-9. TESON, A., AND A. M. M. DE REMES LENICOV. 1979. Estrepsipteros parasitoides de Hymenopteros (Insecta: Strepsiptera). Rev. Soc. Ent. Argentina, Tomo 38 (1-4): 115-22. WHITCOMB, W. H., A. BHATKAR, AND J. C. NICKERSON. 1973. Predators of Solenopsis invicta queens prior to colony establishment. Environ. Ent. 2: 1101-3. WILLIAMS, R. N., J. R. PANAIA, D. GALLO, AND W. H. WHITCOMB. 1973. Fire ants attacked by phorid flies. Florida Ent. 56: 259-62. , AND W. H. WHITCOMB. 1974. Parasites of fire ants in South America. Proc. Tall Timbers Conf. Ecol. Anim. Control Habitat Manage. 5: 49-59. WOJCIK, D. P. 1975. Biology of Myrmecophodius excavaticollis (Blanchard) and Euparia castanea Serville (Coleoptera: Scarabaeidae) and their relationships to Solenopsis pp. (Hymenoptera: Formicidae). Ph.D. thesis, University of Florida, Gainesville, Florida. 74 p.}, number={1}, journal={FLORIDA ENTOMOLOGIST}, author={APPERSON, CS and ADAMS, CT}, year={1983}, pages={121–126} } @article{apperson_axtell_1981, title={Arthropods associated with Eurasian watermilfoil in the Currituck Sound, North Carolina}, volume={16}, number={1}, journal={Journal of the Georgia Entomological Society}, author={Apperson, C. S. and Axtell, R. C.}, year={1981}, pages={53–59} } @article{apperson_axtell_1981, title={Arthropods associated with shoreline deposits of Eurasian watermilfoil in the Currituck Sound, North Carolina}, volume={16}, number={1}, journal={Journal of the Georgia Entomological Society}, author={Apperson, C. S. and Axtell, R. C.}, year={1981}, pages={53} } @article{apperson_yows_madison_1978, title={RESISTANCE TO METHYL PARATHION IN CHAOBORUS-ASTICTOPUS(DIPTERA-CHAOBORIDAE)FROM CLEAR LAKE, CALIFORNIA}, volume={71}, ISSN={["0022-0493"]}, DOI={10.1093/jee/71.5.772}, abstractNote={In 1975, three treatments of methyl parathion applied to Clear Lake at rates of 3.3 ppb failed to control Chaoborus astictopus Dyar and Shannon. Periodic sampling revealed that a 36X increase in the density of early instars and a 6X increase in the density of overwintering 4th instars had occurred in 1975 relative to 1974. Treatment failures were caused by the development of a 10X level of resistance to methyl parathion by 1st instars.}, number={5}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={APPERSON, CS and YOWS, D and MADISON, C}, year={1978}, pages={772–773} }