@article{ponnusamy_travanty_watson_seagle_boyce_reiskind_2024, title={Microbiome of Invasive Tick Species Haemaphysalis Longicornis in North Carolina, USA}, volume={15}, ISSN={["2075-4450"]}, url={https://doi.org/10.3390/insects15030153}, DOI={10.3390/insects15030153}, abstractNote={Ticks are one of the most important vectors of human and animal disease worldwide. In addition to pathogens, ticks carry a diverse microbiota of symbiotic and commensal microorganisms. In this study, we used next-generation sequencing (NGS) to survey the microbiomes of Haemaphysalis longicornis (Acari: Ixodidae) at different life stages collected from field populations in North Carolina (NC), USA. Sequence analyses were performed using QIIME2 with the DADA2 plugin and taxonomic assignments using the Greengenes database. Following quality filtering and rarefaction, the bacterial DNA sequences were assigned to 4795 amplicon sequence variants (ASVs) in 105 ticks. A core microbiome of H. longicornis was conserved across all ticks analyzed, and included bacterial taxa: Coxiella, Sphingomonas, Staphylococcus, Acinetobacter, Pseudomonas, Sphingomonadaceae, Actinomycetales, and Sphingobium. Less abundant bacterial taxa, including Rickettsia and Aeromonas, were also identified in some ticks. We discovered some ASVs that are associated with human and animal infections among the identified bacteria. Alpha diversity metrics revealed significant differences in bacterial diversity between life stages. Beta diversity metrics also revealed that bacterial communities across the three life stages were significantly different, suggesting dramatic changes in the microbiome as ticks mature. Based on these results, additional investigation is necessary to determine the significance of the Haemaphysalis longicornis microbiome for animal and human health.}, number={3}, journal={INSECTS}, author={Ponnusamy, Loganathan and Travanty, Nicholas V. and Watson, D. Wes and Seagle, Steven W. and Boyce, Ross M. and Reiskind, Michael H.}, year={2024}, month={Mar} }
 @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{richardson_roe_apperson_ponnusamy_2023, title={Rickettsia amblyommatis in Ticks: A Review of Distribution, Pathogenicity, and Diversity}, url={https://doi.org/10.3390/microorganisms11020493}, DOI={10.3390/microorganisms11020493}, abstractNote={Rickettsia amblyommatis is a potentially pathogenic species of Rickettsia within the spotted fever group vectored by ticks. While many studies have been published on this species, there is debate over its pathogenicity and the inhibitory role it plays in diagnosing illnesses caused by other spotted fever group Rickettsia species. Many publications have recorded the high infection prevalence of R. amblyommatis in tick populations at a global scale. While this species is rather ubiquitous, questions remain over the epidemiological importance of this possible human pathogen. With tick-borne diseases on the rise, understanding the exact role that R. amblyommatis plays as a pathogen and inhibitor of infection relative to other tick-borne pathogens will help public health efforts. The goal of this review was to compile the known literature on R. amblyommatis, review what we know about its geographic distribution, tick vectors, and pathogenicity, assess relatedness between various international strains from ticks by phylogenetic analysis and draw conclusions regarding future research needed.}, journal={Microorganisms}, author={Richardson, Elise A. and Roe, R. Michael and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2023}, month={Feb} }
 @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
               Host feeding patterns and the prevalence of infection with Rickettsia parkeri were determined for the primary vector, Amblyomma maculatum Koch as well as sympatric tick species A. americanum (Linnaeus) and Dermacentor variabilis (Say) collected from a reconstructed prairie in the Piedmont region of North Carolina during 2011 and 2012. The occurrence of R. parkeri among A. maculatum adults and nymphs was 36.9% (45/122) and 33.3% (2/6), respectively. Rickettsia parkeri was detected in a single male A. americanum 2.3% (1/43). A PCR-reverse line blot hybridization assay of a 12S rDNA fragment amplified from remnant larval and nymphal bloodmeals of host-seeking ticks was used to identify bloodmeal hosts. Of the tick samples tested, bloodmeal host identification was successful for 29.3% (12/41) of adult A. americanum and 39.2% (20/51) of adult D. variabilis. For A. maculatum, bloodmeal host identification was successful for 50% (61/122) of adults collected from vegetation and 100% (4/4) of nymphs removed from cotton rats (Sigmodon hispidus Say and Ord). The cotton rat was the most common bloodmeal host with 59.0% (36/61) identified for adult A. maculatum. No statistically significant association was observed, however, between bloodmeal host and pathogen prevalence for any tick species. While the cotton rat was an important bloodmeal host for A. maculatum nymphs, this vertebrate did not appear to be the primary source of R. parkeri infection for A. maculatum.}, 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} }
 @misc{chen_roe_ponnusamy_2022, title={Biology, Systematics, Microbiome, Pathogen Transmission and Control of Chiggers (Acari: Trombiculidae, Leeuwenhoekiidae) with Emphasis on the United States}, volume={19}, ISSN={["1660-4601"]}, url={https://doi.org/10.3390/ijerph192215147}, DOI={10.3390/ijerph192215147}, abstractNote={Chiggers are the larval stage of Trombiculidae and Leeuwenhoekiidae mites of medical and veterinary importance. Some species in the genus Leptotrombidium and Herpetacarus vector Orientia species, the bacteria that causes scrub typhus disease in humans. Scrub typhus is a life-threatening, febrile disease. Chigger bites can also cause dermatitis. There were 248 chigger species reported from the US from almost every state. However, there are large gaps in our knowledge of the life history of other stages of development. North American wide morphological keys are needed for better species identification, and molecular sequence data for identification are minimal and not clearly matched with morphological data. The role of chiggers in disease transmission in the US is especially understudied, and the role of endosymbionts in Orientia infection are suggested in the scientific literature but not confirmed. The most common chiggers in the eastern United States were identified as Eutrombicula alfreddugesi but were likely misidentified and should be replaced with Eutrombicula cinnabaris. Scrub typhus was originally believed to be limited to the Tsutsugamushi Triangle and the chigger genus, Leptotrombidium, but there is increasing evidence this is not the case. The potential of Orientia species establishing in the US is high. In addition, several other recognized pathogens to infect humans, namely Hantavirus, Bartonella, Borrelia, and Rickettsia, were also detected in chiggers. The role that chiggers play in these disease transmissions in the US needs further investigation. It is possible some of the tick-borne diseases and red meat allergies are caused by chiggers.}, number={22}, journal={INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH}, author={Chen, Kaiying and Roe, R. Michael and Ponnusamy, Loganathan}, year={2022}, month={Nov} }
 @article{dhammi_krestchmar_zhu_ponnusamy_gould_reisig_kurtz_roe_2022, title={Impact of Caterpillar Increased Feeding Rates on Reduction of Bt Susceptibility}, volume={23}, ISSN={["1422-0067"]}, url={https://www.mdpi.com/1422-0067/23/23/14856}, DOI={10.3390/ijms232314856}, abstractNote={The use of insect-resistant transgenic crops producing Bacillus thuringiensis protein Cry toxins (Bt) to control caterpillars is wide-spread. Development of a mechanism to prevent Bt from reaching its target site in the digestive system could result in Bt resistance and resistance to other insecticides active per os. Increased feeding rates by increasing temperature in tobacco budworms, Chloridea virescens, and bollworms, Helicoverpa zea, decreased Bt Cry1Ac susceptibility and mortality. The same was found in C. virescens for Bollgard II plant extract containing Bt Cry1Ac and Cry2Ab2 toxins. Furthermore, H. zea from the same inbred laboratory colony that fed faster independent of temperature manipulation were less susceptible to Bt intoxication. A laboratory derived C. virescens Bt resistant strain demonstrated a higher feeding rate on non-Bt artificial diet than the parental, Bt susceptible strain. A laboratory-reared Bt resistant fall armyworm, Spodoptera frugiperda, strain also fed faster on non-Bt diet compared to Bt susceptible caterpillars of the same species, both originally collected from corn. The studies in toto and the literature reviewed support the hypothesis that increased feeding rate is a behavioral mechanism for reducing caterpillar susceptibility to Bt. Its possible role in resistance needs further study.}, number={23}, journal={INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES}, author={Dhammi, Anirudh and Krestchmar, Jaap B. and Zhu, Jiwei and Ponnusamy, Loganathan and Gould, Fred and Reisig, Dominic and Kurtz, Ryan W. and Roe, R. Michael}, year={2022}, month={Dec} }
 @article{chen_ponnusamy_mouhamadou_fodjo_sadia_affoue_deguenon_roe_2022, title={Internal and external microbiota of home-caught Anopheles coluzzii (Diptera: Culicidae) from Cote d'Ivoire, Africa: Mosquitoes are filthy}, volume={17}, ISSN={["1932-6203"]}, url={https://doi.org/10.1371/journal.pone.0278912}, DOI={10.1371/journal.pone.0278912}, abstractNote={Over the past 10 years, studies using high-throughput 16S rRNA gene sequencing have shown that mosquitoes harbor diverse bacterial communities in their digestive system. However, no previous research has examined the total bacteria community inside versus outside of mosquitoes and whether bacteria found on the outside could represent a potential health threat through mechanical transfer. We examined the bacterial community of the external surface and internal body of female Anopheles coluzzii adults collected from homes in Côte d’Ivoire, Africa, by Illumina sequencing of the V3 to V4 region of 16S rRNA gene. Anopheles coluzzii is in the Anopheles gambiae sensu lato (s.l.) species complex and important in the transmission of malaria. The total 16S rRNA reads were assigned to 34 phyla, 73 orders, 325 families, and 700 genera. At the genus level, the most abundant genera inside and outside combined were Bacillus, Staphylococcus, Enterobacter, Corynebacterium, Kocuria, Providencia, and Sphingomonas. Mosquitoes had a greater diversity of bacterial taxa internally compared to the outside. The internal bacterial communities were similar between homes, while the external body samples were significantly different between homes. The bacteria on the external body were associated with plants, human and animal skin, and human and animal infections. Internally, Rickettsia bellii and Rickettsia typhi were found, potentially of importance, since this genus is associated with human diseases. Based on these findings, further research is warranted to assess the potential mechanical transmission of bacteria by mosquitoes moving into homes and the importance of the internal mosquito microbiota in human health.}, number={12}, journal={PLOS ONE}, author={Chen, Kaiying and Ponnusamy, Loganathan and Mouhamadou, Chouaibou S. and Fodjo, Behi Kouadio and Sadia, Gba Christabelle and Affoue, France Paraudie Kouadio and Deguenon, Jean M. and Roe, R. Michael}, editor={Terenius, OlleEditor}, year={2022}, month={Dec} }
 @article{richardson_ponnusamy_roe_2022, title={Mechanical Acaricides Active against the Blacklegged Tick, Ixodes scapularis}, volume={13}, ISSN={["2075-4450"]}, url={https://www.mdpi.com/2075-4450/13/8/672}, DOI={10.3390/insects13080672}, abstractNote={Cases of Lyme disease in humans are on the rise in the United States and Canada. The vector of the bacteria that causes this disease is the blacklegged tick, Ixodes scapularis. Current control methods for I. scapularis mainly involve chemical acaricides. Unfortunately, ticks are developing resistance to these chemicals, and more and more, the public prefers non-toxic alternatives to chemical pesticides. We discovered that volcanic glass, ImergardTM WP, and other industrial minerals such as Celite 610 were efficacious mechanical insecticides against mosquitoes, filth flies, and agricultural pests. In this report, when 6–10- and 50–70-day old unfed I. scapularis nymphs were dipped for 1–2 s into Celite, the time to 50% mortality (LT50) was 66.8 and 81.7 min, respectively, at 30 °C and 50% relative humidity (RH). The LT50 was actually shorter at a higher 70% RH, 43.8 min. Scanning electron microscopy showed that the ticks were coated over most of their body surface, including partial to almost total coverage of the opening to their respiratory system. The other mechanical insecticide, Imergard, had similar efficacy against blacklegged unfed nymphs with an LT50 at 30 °C and 50% RH of 70.4 min. Although more research is needed, this study suggests that industrial minerals could be used as an alternative to chemical pesticides to control ticks and Lyme disease.}, number={8}, journal={INSECTS}, author={Richardson, Elise A. and Ponnusamy, Loganathan and Roe, R. Michael}, year={2022}, month={Aug} }
 @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://doi.org/10.3390/microorganisms10071342}, 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{deguenon_dhammi_ponnusamy_travanty_cave_lawrie_mott_reisig_kurtz_roe_2021, title={Bacterial Microbiota of Field-Collected Helicoverpa zea (Lepidoptera: Noctuidae) from Transgenic Bt and Non-Bt Cotton}, volume={9}, ISSN={["2076-2607"]}, url={https://doi.org/10.3390/microorganisms9040878}, DOI={10.3390/microorganisms9040878}, abstractNote={The bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is an important agricultural pest in U.S. cotton and is managed using transgenic hybrids that produce insecticidal proteins from the bacterium, Bacillus thuringiensis (Bt). The reduced efficacy against H. zea caterpillars of Bt plants expressing Cry toxins is increasing in the field. In a first step towards understanding Bt cotton–bollworm–microbiota interactions, we investigated the internal bacterial microbiota of second–third stadium H. zea collected in the field from non-Bt versus Bt (WideStrike) cotton in close proximity (in North Carolina, USA). The bacterial populations were analyzed using culture-dependent and -independent molecular approaches. We found that WideStrike samples had a higher bacterial density and diversity per larva than insects collected from non-Bt cotton over two field seasons: 8.42 ± 0.23 and 5.36 ± 0.75 (log10 colony forming units per insect) for WideStrike compared to 6.82 ± 0.20 and 4.30 ± 0.56 for non-Bt cotton for seasons 1 and 2, respectively. Fifteen phyla, 103 families, and 229 genera were identified after performing Illumina sequencing of the 16S rRNA. At the family level, Enterobacteriaceae and Enterococcaceae were the most abundant taxa. The Enterococcaceae family was comprised mostly of Enterococcus species (E. casseliflavus and another Enterococcus sp.). Members of the Enterococcus genus can acidify their environment and can potentially reduce the alkaline activation of some Bt toxins. These findings argue for more research to better understand the role of cotton–bollworm–bacteria interactions and the impact on Bt toxin caterpillar susceptibility.}, number={4}, journal={MICROORGANISMS}, publisher={MDPI AG}, author={Deguenon, Jean M. and Dhammi, Anirudh and Ponnusamy, Loganathan and Travanty, Nicholas V and Cave, Grayson and Lawrie, Roger and Mott, Dan and Reisig, Dominic and Kurtz, Ryan and Roe, R. Michael}, year={2021}, month={Apr} }
 @article{lawrie_mitchell_deguenon_ponnusamy_reisig_pozo-valdivia_kurtz_roe_2022, title={Characterization of Long Non-Coding RNAs in the Bollworm, Helicoverpa zea, and Their Possible Role in Cry1Ac-Resistance}, volume={13}, ISSN={["2075-4450"]}, url={https://www.mdpi.com/2075-4450/13/1/12}, DOI={10.3390/insects13010012}, abstractNote={Multiple insect pest species have developed field resistance to Bt-transgenic crops. There has been a significant amount of research on protein-coding genes that contribute to resistance, such as the up-regulation of protease activity or altered receptors. However, our understanding of the role of non-protein-coding mechanisms in Bt-resistance is minimal, as is also the case for resistance to chemical pesticides. To address this problem relative to Bt, RNA-seq was used to examine statistically significant, differential gene expression between a Cry1Ac-resistant (~100-fold resistant) and Cry1Ac-susceptible strain of Helicoverpa zea, a prevalent caterpillar pest in the USA. Significant differential expression of putative long non-coding RNAs (lncRNAs) was found in the Cry1Ac-resistant strain (58 up- and 24 down-regulated gene transcripts with an additional 10 found only in resistant and four only in susceptible caterpillars). These lncRNAs were examined as potential pseudogenes and for their genomic proximity to coding genes, both of which can be indicative of regulatory relationships between a lncRNA and coding gene expression. A possible pseudogenic lncRNA was found with similarities to a cadherin. In addition, putative lncRNAs were found significantly proximal to a serine protease, ABC transporter, and CYP coding genes, potentially involved in the mechanism of Bt and/or chemical insecticide resistance. Characterization of non-coding genetic mechanisms in Helicoverpa zea will improve the understanding of the genomic evolution of insect resistance, improve the identification of specific regulators of coding genes in general (some of which could be important in resistance), and is the first step for potentially targeting these regulators for pest control and resistance management (using molecular approaches, such as RNAi and others).}, number={1}, journal={INSECTS}, author={Lawrie, Roger D. and Mitchell, Robert D. and Deguenon, Jean Marcel and Ponnusamy, Loganathan and Reisig, Dominic and Pozo-Valdivia, Alejandro Del and Kurtz, Ryan W. and Roe, Richard Michael}, year={2022}, month={Jan} }
 @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{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{lawrie_mitchell iii_deguenon_ponnusamy_reisig_pozo-valdivia_kurtz_roe_2020, title={Multiple Known Mechanisms and a Possible Role of an Enhanced Immune System in Bt-Resistance in a Field Population of the Bollworm, Helicoverpa zea: Differences in Gene Expression with RNAseq}, volume={21}, ISSN={1422-0067}, url={http://dx.doi.org/10.3390/ijms21186528}, DOI={10.3390/ijms21186528}, abstractNote={Several different agricultural insect pests have developed field resistance to Bt (Bacillus thuringiensis) proteins (ex. Cry1Ac, Cry1F, etc.) expressed in crops, including corn and cotton. In the bollworm, Helicoverpa zea, resistance levels are increasing; recent reports in 2019 show up to 1000-fold levels of resistance to Cry1Ac, a major insecticidal protein in Bt-crops. A common method to analyze global differences in gene expression is RNA-seq. This technique was used to measure differences in global gene expression between a Bt-susceptible and Bt-resistant strain of the bollworm, where the differences in susceptibility to Cry1Ac insecticidal proteins were 100-fold. We found expected gene expression differences based on our current understanding of the Bt mode of action, including increased expression of proteases (trypsins and serine proteases) and reduced expression of Bt-interacting receptors (aminopeptidases and cadherins) in resistant bollworms. We also found additional expression differences for transcripts that were not previously investigated, i.e., transcripts from three immune pathways-Jak/STAT, Toll, and IMD. Immune pathway receptors (ex. PGRPs) and the IMD pathway demonstrated the highest differences in expression. Our analysis suggested that multiple mechanisms are involved in the development of Bt-resistance, including potentially unrecognized pathways.}, number={18}, journal={International Journal of Molecular Sciences}, publisher={MDPI AG}, author={Lawrie, Roger D. and Mitchell III, Robert D. and Deguenon, Jean Marcel and Ponnusamy, Loganathan and Reisig, Dominic and Pozo-Valdivia, Alejandro Del and Kurtz, Ryan W. and Roe, R. Michael}, year={2020}, month={Sep}, pages={6528} }
 @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
               Phlebotomine sand flies are worldwide vectors of Leishmania parasites as well as other bacterial and viral pathogens. Due to the variable impact of traditional vector control practices, a more ecologically based approach is needed. The goal of this study was to isolate bacteria from the most attractive substrate to gravid Phlebotomus papatasi Scopoli sand flies and determine the role of bacterial volatiles in the oviposition attractancy of P. papatasi using behavioral assays. We hypothesized that gravid sand flies are attracted to bacterially derived semiochemical cues associated with breeding sites. Bacteria were isolated from a larvae-conditioned rearing medium, previously shown to be highly attractive to sand flies. The isolated bacteria were identified by amplifying and sequencing 16S rDNA gene fragments, and 12 distinct bacterial species were selected for two-choice olfactometer bioassays. The mix of 12 bacterial isolates elicited strong attraction at the lower concentration of 107 cells per ml and significant repellence at a high concentration of 109 cells per ml. Three individual isolates (SSI-2, SSI-9, and SSI-11) were particularly attractive at low doses. In general, we observed dose-related effects, with some bacterial isolates stimulating negative and some positive dose–response curves in sand fly attraction. Our study confirms the important role of saprophytic bacteria, gut bacteria, or both, in guiding the oviposition-site selection behavior of sand flies. Identifying the specific attractive semiochemical cues that they produce could lead to development of an attractive lure for surveillance and control of sand flies.}, 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{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{deguenon_travanty_zhu_carr_denning_reiskind_watson_roe_ponnusamy_2019, title={Exogenous and endogenous microbiomes of wild-caught Phormia regina (Diptera: Calliphoridae) flies from a suburban farm by 16S rRNA gene sequencing}, volume={9}, ISSN={["2045-2322"]}, url={http://dx.doi.org/10.1038/s41598-019-56733-z}, DOI={10.1038/s41598-019-56733-z}, abstractNote={AbstractThe black blow fly,Phormia regina(Meigen) (Diptera: Calliphoridae) is one of the most abundant carrion flies in North America. Calliphorids are important in agriculture and animal production, veterinary sciences, forensics and medical entomology. While the role of flies in the epidemiology of human and animal diseases is an active area of research, little is known about the microorganisms associated with these insects. We examined the diversity of wild-caught black blow fly endogenous (internal body) and exogenous (external body) microbial communities using 16S rRNA gene sequencing. Overall, 27 phyla, 171 families and 533 genera were detected, and diversity was significantly higher (P< 0.05) on external body surfaces. At the genus level,Dysgonomonas,Ignatzschineria,Acinetobacter,Vagococcus,Myroides, andWohlfahrtiimonaswere predominant. Cloning and sequencing of nearly full-length fragments of the 16S rRNA gene showed that some of the species identified are known to be pathogenic to humans, animals, and plants.Myroides odoratimimusandAcinetobacter radioresistensare well-known, multi-drug resistant bacteria. These results provide a snapshot of the microbial communities harbored by adult black blow flies and call for more comprehensive studies to better characterize the role these flies may play in the transmission of pathogenic microorganisms.}, journal={SCIENTIFIC REPORTS}, author={Deguenon, Jean M. and Travanty, Nicholas and Zhu, Jiwei and Carr, Ann and Denning, Steven and Reiskind, Michael H. and Watson, David W. and Roe, R. Michael and Ponnusamy, Loganathan}, year={2019}, month={Dec} }
 @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{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{dhammi_krestchmar_ponnusamy_bacheler_reisig_herbert_del pozo-valdivia_roe_2016, title={Biology, pest status, microbiome and control of kudzu bug (Hemiptera: Heteroptera: Plataspidae): a new invasive pest in the U.S.}, volume={17}, ISSN={["1422-0067"]}, url={http://dx.doi.org/10.3390/ijms17091570}, DOI={10.3390/ijms17091570}, abstractNote={Soybean is an important food crop, and insect integrated pest management (IPM) is critical to the sustainability of this production system. In recent years, the introduction into the United States of the kudzu bug currently identified as Megacopta cribraria (F.), poses a threat to soybean production. The kudzu bug was first discovered in the state of Georgia, U.S. in 2009 and since then has spread to most of the southeastern states. Because it was not found in the North American subcontinent before this time, much of our knowledge of this insect comes from research done in its native habitat. However, since the U.S. introduction, studies have been undertaken to improve our understanding of the kudzu bug basic biology, microbiome, migration patterns, host selection and management in its expanding new range. Researchers are not only looking at developing IPM strategies for the kudzu bug in soybean, but also at its unique relationship with symbiotic bacteria. Adult females deposit bacterial packets with their eggs, and the neonates feed on these packets to acquire the bacteria, Candidatus Ishikawaella capsulata. The kudzu bug should be an informative model to study the co-evolution of insect function and behavior with that of a single bacteria species. We review kudzu bug trapping and survey methods, the development of bioassays for insecticide susceptibility, insecticide efficacy, host preferences, impact of the pest on urban environments, population expansion, and the occurrence of natural enemies. The identity of the kudzu bug in the U.S. is not clear. We propose that the kudzu bug currently accepted as M. cribraria in the U.S. is actually Megacopta punctatissima, with more work needed to confirm this hypothesis.}, number={9}, journal={Int. J. Mol. Sci}, publisher={MDPI AG}, author={Dhammi, Anirudh and Krestchmar, Jaap B. and Ponnusamy, Loganathan and Bacheler, Jack S. and Reisig, Dominic D. and Herbert, Ames and Del Pozo-Valdivia, Alejandro I. and Roe, R. Michael}, year={2016} }
 @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
          
            A novel nested PCR assay was developed to detect
            Rickettsia
            spp. in ticks and tissue samples from humans and laboratory animals. Primers were designed for the nested run to amplify a variable region of the 23S-5S intergenic spacer (IGS) of
            Rickettsia
            spp. The newly designed primers were evaluated using genomic DNA from 11
            Rickettsia
            species belonging to the spotted fever, typhus, and ancestral groups and, in parallel, compared to other
            Rickettsia
            -specific PCR targets (
            ompA
            ,
            gltA
            , and the 17-kDa protein gene). The new 23S-5S IGS nested PCR assay amplified all 11
            Rickettsia
            spp., but the assays employing other PCR targets did not. The novel nested assay was sensitive enough to detect one copy of a cloned 23S-5S IGS fragment from “
            Candidatus
            Rickettsia amblyommii.” Subsequently, the detection efficiency of the 23S-5S IGS nested assay was compared to those of the other three assays using genomic DNA extracted from 40 adult
            Dermacentor variabilis
            ticks. The nested 23S-5S IGS assay detected
            Rickettsia
            DNA in 45% of the ticks, while the amplification rates of the other three assays ranged between 5 and 20%. The novel PCR assay was validated using clinical samples from humans and laboratory animals that were known to be infected with pathogenic species of
            Rickettsia
            . The nested 23S-5S IGS PCR assay was coupled with reverse line blot hybridization with species-specific probes for high-throughput detection and simultaneous identification of the species of
            Rickettsia
            in the ticks. “
            Candidatus
            Rickettsia amblyommii,”}, 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{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={SummaryThe spirochaete (Borrelia burgdorferi) associated with Lyme disease was detected in questing ticks and rodents during a period of 18 years, 1991–2009, at five locations on the Outer Banks of North Carolina. The black‐legged tick (Ixodes scapularis) was collected at varied intervals between 1991 and 2009 and examined for B. burgdorferi. The white‐footed mouse (Peromyscus leucopus), house mouse (Mus musculus) marsh rice rat (Oryzomys palustris), marsh rabbit (Sylvilagus palustris), eastern cottontail (Sylvilagus floridanus) and six‐lined racerunner (Cnemidophorus sexlineatus) were live‐trapped, and their tissues cultured to isolate spirochaetes. Borrelia burgdorferi isolates were obtained from questing adult I. scapularis and engorged I. scapularis removed from P. leucopus, O. palustris and S. floridanus. The prevalence of B. burgdorferi infection was variable at different times and sites ranging from 7 to 14% of examined questing I. scapularis. Mitochondrial (16S) rRNA gene phylogenetic analysis from 65 adult I. scapularis identified 12 haplotypes in two major clades. Nine haplotypes were associated with northern/Midwestern I. scapularis populations and three with southern I. scapularis populations. Sixteen isolates obtained from tick hosts in 2005 were confirmed to be B. burgdorferi by amplifying and sequencing of 16S rRNA and 5S‐23S intergenic spacer fragments. The sequences had 98–99% identity to B. burgdorferi sensu stricto strains B31, JD1 and M11p. Taken together, these studies indicate that B. burgdorferi sensu stricto is endemic in questing I. scapularis and mammalian tick hosts on the Outer Banks of North Carolina.}, 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{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{evidence foraedes aegypti(diptera: culicidae) oviposition on boats in the peruvian amazon_2015, url={http://dx.doi.org/10.1093/jme/tjv048}, DOI={10.1093/jme/tjv048}, abstractNote={ABSTRACT 
 Dengue vector Aedes aegypti L. is invading peri-urban and rural areas throughout Latin America. Our previous research in the Peruvian Amazon has shown that river boats are heavily infested with immature and adult Ae. aegypti mosquitoes, likely playing a major role in their long-distance dispersal and successful invasion. However, the presence of immature mosquitoes provides no information about the timing of oviposition, and whether it took place in the boats. Here, we used baited ovitraps deployed on river boats to test the hypothesis that Ae. aegypti oviposition occurs during boat travel. We deployed 360 ovitraps on 60 different barges during August and October of 2013, and February 2014 (with 20 barges sampled during each month). We found that Ae. aegypti mosquitoes in 22 individual ovitraps from 15 of the 60 barges (premise index 25%) across all sampling dates. Further, the distribution of Ae. aegypti egg abundance was highly aggregated: 2.6% of traps (N = 7) were responsible for 71.8% of eggs found, and 1.5% of traps (N = 4) were responsible for all (100%) of the larvae found. Similarly, 5% of boats were responsible for the 71.47% of eggs. Our results provide strong evidence that Ae. aegypti oviposition commonly occurs during boat travel. Baited ovitraps could represent a cost-effective means of monitoring and controlling mosquito populations on boats.}, journal={Journal of Medical Entomology}, year={2015}, month={Jul} }
 @article{long-lasting permethrin-impregnated clothing protects against mosquito bites in outdoor workers_2015, url={http://dx.doi.org/10.4269/ajtmh.15-0130}, DOI={10.4269/ajtmh.15-0130}, abstractNote={Outdoor exposure to mosquitoes is a risk factor for many diseases, including malaria and dengue. We have previously shown that long-lasting permethrin-impregnated clothing protects against tick and chigger bites in a double-blind randomized controlled trial in North Carolina outdoor workers. Here, we evaluated whether this clothing is protective against mosquito bites by measuring changes in antibody titers to mosquito salivary gland extracts. On average, there was a 10-fold increase in titer during the spring and summer when mosquito exposure was likely to be the highest. During the first year of the study, the increase in titer in subjects wearing treated uniforms was 2- to 2.5-fold lower than that of control subjects. This finding suggests that long-lasting permethrin-impregnated clothing provided protection against mosquito bites.}, journal={The American Journal of Tropical Medicine and Hygiene}, year={2015}, month={Oct} }
 @article{ponnusamy_schal_wesson_arellano_apperson_2015, title={Oviposition responses of Aedes mosquitoes to bacterial isolates from attractive bamboo infusions}, volume={8}, ISSN={1756-3305}, url={http://dx.doi.org/10.1186/s13071-015-1068-y}, DOI={10.1186/s13071-015-1068-y}, abstractNote={The mosquitoes Aedes aegypti and Aedes albopictus are vectors of pathogenic viruses that cause major human illnesses including dengue, yellow fever and chikungunya. Both mosquito species are expanding their geographic distributions and now occur worldwide in temperate and tropical climates. Collection of eggs in oviposition traps (ovitraps) is commonly used for monitoring and surveillance of container-inhabiting Aedes populations by public health agencies charged with managing mosquito-transmitted illness. Addition of an organic infusion in these traps increases the number of eggs deposited. Gravid females are guided to ovitraps by volatile chemicals produced from the breakdown of organic matter by microbes. We previously isolated and cultured 14 species of bacteria from attractive experimental infusions, made from the senescent leaves of canebrake bamboo (Arundinaria gigantea). Cultures were grown for 24 h at 28 °C with constant shaking (120 rpm) and cell densities were determined with a hemocytometer. Behavioral responses to single bacterial isolates and to a mix of isolates at different cell densities were evaluated using two-choice sticky-screen bioassay methods with gravid Ae. aegypti and Ae. albopictus. In behavioral assays of a mix of 14 bacterial isolates, significantly greater attraction responses were exhibited by Ae. aegypti and Ae. albopictus to bacterial densities of 107 and 108 cells/mL than to the control medium. When we tested single bacterial isolates, seven isolates (B1, B2, B3, B5, B12, B13 and B14) were significantly attractive to Ae. aegypti, and six isolates (B1, B5, B7, B10, B13 and B14) significantly attracted Ae. albopictus. Among all the isolates tested at three different cell densities, bacterial isolates B1, B5, B13 and B14 were highly attractive to both Aedes species. Our results show that at specific cell densities, some bacteria significantly influence the attraction of gravid Ae. aegypti and Ae. albopictus females to potential oviposition sites. Attractive bacterial isolates, when formulated for sustained release of attractants, could be coupled with an ovitrap containing a toxicant to achieve area-wide management of Aedes mosquitoes.}, number={1}, journal={Parasites & Vectors}, publisher={Springer Science and Business Media LLC}, author={Ponnusamy, Loganathan and Schal, Coby and Wesson, Dawn M. and Arellano, Consuelo and Apperson, Charles S.}, year={2015}, month={Sep} }
 @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
          
            Ixodes scapularis
            is the principal vector of Lyme disease on the East Coast and in the upper Midwest regions of the United States, yet the tick is also present in the Southeast, where Lyme disease is absent or rare. A closely related species,
            I. affinis
            , also carries the pathogen in the South but does not seem to transmit it to humans. In order to better understand the geographic diversity of the tick, we analyzed the microbiota of 104 adult
            I. scapularis
            and 13 adult
            I. affinis
            ticks captured in 19 locations in South Carolina, North Carolina, Virginia, Connecticut, and New York. Initially, ticks from 4 sites were analyzed by 454 pyrosequencing. Subsequently, ticks from these sites plus 15 others were analyzed by sequencing with an Illumina MiSeq machine. By both analyses, the microbiomes of female ticks were significantly less diverse than those of male ticks. The dissimilarity between tick microbiomes increased with distance between sites, and the state in which a tick was collected could be inferred from its microbiota. The genus
            Rickettsia
            was prominent in all locations.
            Borrelia
            was also present in most locations and was present at especially high levels in one site in western Virginia. In contrast, members of the family
            Enterobacteriaceae
            were very common in North Carolina
            I. scapularis
            ticks but uncommon in
            I. scapularis
            ticks from other sites and in North Carolina
            I. affinis
            ticks. These data suggest substantial variations in the
            Ixodes
            microbiota in association with geography, species, and sex.
          }, 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{advancing integrated tick management to mitigate burden of tick-borne diseases_2014, url={http://dx.doi.org/10.1564/v25_dec_10}, DOI={10.1564/v25_dec_10}, journal={Outlooks on Pest Management}, year={2014}, month={Dec} }
 @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
          
            Ticks are important vectors for many emerging pathogens. However, they are also infected with many symbionts and commensals, often competing for the same niches. In this paper, we characterize the microbiome of
            Amblyomma americanum
            (Acari: Ixodidae), the lone star tick, in order to better understand the evolutionary relationships between pathogens and nonpathogens. Multitag pyrosequencing of prokaryotic 16S rRNA genes (16S rRNA) was performed on 20 lone star ticks (including males, females, and nymphs). Pyrosequencing of the rickettsial
            sca0
            gene (also known as
            ompA
            or
            rompA
            ) was performed on six ticks. Female ticks had less diverse microbiomes than males and nymphs, with greater population densities of
            Rickettsiales
            . The most common members of
            Rickettsiales
            were “
            Candidatus
            Rickettsia amblyommii” and “
            Candidatus
            Midichloria mitochondrii.” “
            Ca
            . Rickettsia amblyommii” was 2.6-fold more common in females than males, and there was no sequence diversity in the
            sca0
            gene. These results are consistent with a predominantly vertical transmission pattern for “
            Ca
            . Rickettsia amblyommii.”}, 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{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{wesson_morrison_paz soldan_moudy_long_ponnusamy_mohler_astete_ayyash_halsey_et al._2012, title={Lethal ovitraps and dengue prevention: report from Iquitos, Peru}, volume={16}, ISSN={1201-9712}, url={http://dx.doi.org/10.1016/j.ijid.2012.05.687}, DOI={10.1016/j.ijid.2012.05.687}, abstractNote={Background: Dengue viruses are transmitted by container-inhabiting Aedes (Stegomyia) mosquitoes, primarily Aedes aegypti and also Aedes albopictus. After female mosquitoes acquire the virus when taking blood from an infected human host, they use a variety of cues to identify potential oviposition sites, where they must deposit eggs before taking another bloodmeal. For several years, we have worked to identify those semiochemical cues and to develop a more effective lethal ovitrap (Attractive Lethal OviTrap = ALOT) for Ae. aegypti control, with concentration on oviposition attractants and stimulants. Here we describe the ALOT, as well as focus group and modeling work designed to identify important trap attributes. We will also present entomological and dengue incidence data from an ongoing field trial in Iquitos, Peru. Methods: Methods to be discussed include large cage trials, and field trials comparing areas with ALOTs to those without. In cage trials, efficacy endpoints included mortality, eggs oviposited in the ALOT and eggs retained by dead females. In small scale field trials, efficacy endpoints included eggs deposited in non-lethal ovitraps, number of female mosquitoes collected, and female gravid and parous status. In the large scale field trial, efficacy is measured by entomological indices (adult index, etc.), by gravid and parous status of female mosquitoes, and by dengue incidence. Results: In large cage trails we consistently have shown 90-98% efficacy of the ALOT compared to normal ovitraps and to typical backyard containers; in two field trials based in New Orleans, Louisiana, we have shown that there are significantly fewer gravid and parous females in areas treated with ALOTs, as compared to untreated areas. Currently, in Iquitos, Peru we are conducting a large scale efficacy trial to assess the ability of the ALOT to reduce dengue transmission. Conclusion: Our results suggest that the ALOT can impact virus transmission because it reduces the number of epidemiologically important (e.g., previously blood-fed) mosquitoes. The ALOT is not designed to be a stand-alone tool for dengue vector control; it should be used as part of an integrated management program (e.g., source reduction, active case surveillance, targeted insecticide treatment, etc).}, journal={International Journal of Infectious Diseases}, publisher={Elsevier BV}, author={Wesson, D. and Morrison, A. and Paz Soldan, V. and Moudy, R. and Long, K. and Ponnusamy, L. and Mohler, J. and Astete, H. and Ayyash, L. and Halsey, E. and et al.}, year={2012}, month={Jun}, pages={e473} }
 @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{bacterial pathogens in ixodid ticks from a piedmont county in north carolina: prevalence of rickettsial organisms_2010, url={http://dx.doi.org/10.1089/vbz.2009.0178}, DOI={10.1089/vbz.2009.0178}, abstractNote={In North Carolina, reported human cases of tick-borne illness, specifically Rocky Mountain spotted fever, have escalated over the past decade. To determine the relative abundance of vectors and to estimate the risk of acquiring a tick-borne illness in peri-residential landscapes, ticks were collected in Chatham County, a typical Piedmont county and, samples of the ticks were tested for infection with selected bacterial pathogens using real-time quantitative polymerase chain reaction assays. Ticks (n = 3746) were collected by flagging vegetation at 26 sites from April to July 2006. The predominant questing tick was Amblyomma americanum (98.5%) with significantly fewer Dermacentor variabilis (1.0%) and Ixodes scapularis (0.5%) collected. Spotted fever group (SFG) rickettsiae were detected in 68.2% of 1590 A. americanum with 56.4% of the molecular isolates identified as Rickettsia amblyommii, an informally named member of the SFG rickettsiae. Comparatively, smaller numbers of A. americanum contained Ehrlichia chaffeensis (1.8%) and Borrelia lonestari (0.4%). Of 15 I. scapularis nymphs tested, 6 (40%) were positive for Borrelia burgdorferi sensu lato. Seven (19.4%) of 36 adult D. variabilis tested positive for Rickettsia montanensis, 4 (11.1%) were positive for R. amblyommii, and 5 (13.9%) were infected with unidentified species of SFG rickettsiae. The tick population in Chatham County contains a diverse array of microbes, some of which are known or potential pathogens. Highest attack rates would be expected from A. americanum ticks, and highest potential risk of infection with a tick-transmitted agent would be to rickettsial organisms, particularly R. amblyommii. Accordingly, longitudinal eco-epidemiology investigations are needed to determine the public health importance of A. americanum infected with rickettsial organisms.}, journal={Vector-Borne and Zoonotic Diseases}, year={2010}, month={Dec} }
 @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{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{host-feeding patterns of aedes albopictus (diptera: culicidae) in relation to availability of human and domestic animals in suburban landscapes of central north carolina._2006, url={https://europepmc.org/articles/PMC2577020}, DOI={10.1093/jmedent/43.3.543}, abstractNote={Aedes albopictus (Skuse) (Diptera: Culicidae) is a major nuisance mosquito and a potential arbovirus vector. The host-feeding patterns of Ae. albopictus were investigated during the 2002 and 2003 mosquito seasons in suburban neighborhoods in Wake County, Raleigh, NC. Hosts of blood-fed Ae. albopictus (n = 1,094) were identified with an indirect enzyme-linked immunosorbent assay, by using antisera made in New Zealand White rabbits to the sera of animals that would commonly occur in peridomestic habitats. Ae. albopictus fed predominantly on mammalian hosts (83%). Common mammalian hosts included humans (24%), cats (21%), and dogs (14%). However, a notable proportion (7%) of bloodmeals also was taken from avian hosts. Some bloodmeals taken from birds were identified to species by a polymerase chain reaction-heteroduplex assay (PCR-HDA). Ae. albopictus fed predominantly on chickens and a northern cardinal. PCR-HDA failed to produce detectable products for 29 (58%) of 50 bloodmeals for which DNA had been amplified, indicating that these mosquitoes took mixed bloodmeals from avian and nonavian hosts. Ae. albopictus preference for humans, dogs, and cats was determined by calculating host-feeding indices for the three host pairs based on the proportion of host specific blood-fed mosquitoes collected in relation to the number of specific hosts per residence as established by a door-to-door survey conducted in 2003. Estimates of the average amount of time that residents and their pets (cats and dogs) spent out of doors were obtained. Host-feeding indices based only on host abundance indicated that Ae. albopictus was more likely to feed on domestic animals. However, when feeding indices were time-weighted, Ae. albopictus fed preferentially upon humans. Ae. albopictus blood feeding on humans was investigated using a STR/PCR-DNA profiling technique that involved amplification of three short tandem repeats loci. Of 40 human bloodmeals, 32 (80%) were from a single human, whereas eight (20%) were multiple bloodmeals taken from more than one human host. We conclude that the blood-feeding preference of Ae. albopictus for mammals will limit acquisition of arboviruses by this species from infected avian amplification hosts. This feeding preference likely limits the vector potential of Ae. albopictus for North American arboviruses.}, journal={Journal of medical entomology}, year={2006}, month={May} }
 @article{swaminathania salitolerans gen. nov., sp. nov., a salt-tolerant, nitrogen-fixing and phosphate-solubilizing bacterium from wild rice (porteresia coarctata tateoka)_2004, url={http://dx.doi.org/10.1099/ijs.0.02817-0}, DOI={10.1099/ijs.0.02817-0}, abstractNote={A novel species, Swaminathania salitolerans gen. nov., sp. nov., was isolated from the rhizosphere, roots and stems of salt-tolerant, mangrove-associated wild rice (Porteresia coarctata Tateoka) using nitrogen-free, semi-solid LGI medium at pH 5·5. Strains were Gram-negative, rod-shaped and motile with peritrichous flagella. The strains grew well in the presence of 0·35 % acetic acid, 3 % NaCl and 1 % KNO3, and produced acid from l-arabinose, d-glucose, glycerol, ethanol, d-mannose, d-galactose and sorbitol. They oxidized ethanol and grew well on mannitol and glutamate agar. The fatty acids 18 : 1ω7c/ω9t/ω12t and 19 : 0cyclo ω8c constituted 30·41 and 11·80 % total fatty acids, respectively, whereas 13 : 1 AT 12–13 was found at 0·53 %. DNA G+C content was 57·6–59·9 mol% and the major quinone was Q-10. Phylogenetic analysis based on 16S rRNA gene sequences showed that these strains were related to the genera Acidomonas, Asaia, Acetobacter, Gluconacetobacter, Gluconobacter and Kozakia in the Acetobacteraceae. Isolates were able to fix nitrogen and solubilized phosphate in the presence of NaCl. Based on overall analysis of the tests and comparison with the characteristics of members of the Acetobacteraceae, a novel genus and species is proposed for these isolates, Swaminathania salitolerans gen. nov., sp. nov. The type strain is PA51T (=LMG 21291T=MTCC 3852T).}, journal={INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY}, year={2004}, month={Jul} }
 @article{[]_2003, url={http://dx.doi.org/10.1023/a:1022645124506}, DOI={10.1023/a:1022645124506}, abstractNote={A novel salt-tolerant, N2-fixing and phosphate-solubilizing, Gluconacetobacter sp. (PA12) tagged with gusA gene, colonized Porteresia coarctata (wild rice) and Pokkali (salt-tolerant variety) more intensively when compared to Ponni (salt-sensitive variety). This was confirmed using a colony-counting method.}, journal={Biotechnology Letters}, year={2003} }
 @article{genetic diversity and relationship between bradyrhizobium strains isolated from blackgram and cowpea_2001, url={http://dx.doi.org/10.1007/s003740100391}, DOI={10.1007/s003740100391}, journal={Biology and Fertility of Soils}, year={2001}, month={Sep} }
 @article{genetic diversity of bradyrhizobium strains isolated from arachis hypogaea_2001, url={http://dx.doi.org/10.1139/w00-139}, DOI={10.1139/w00-139}, abstractNote={Rhizobia are used exclusively in agricultural systems for enhancing the ability of legumes to fix atmospheric nitrogen. Knowledge about the indigenous population is necessary for the selection and application of inoculant strains. In this study, we have assessed the genetic diversity of Bradyrhizobium strains isolated from the host plant, Arachis hypogaea along the coastline of Tamil Nadu. Different populations collected from varying environmental conditions were analysed for salt and pH tolerance. Genetic diversity among the strains was studied using RAPD markers and PCR-RFLP of 16S rDNA and nifD genes. The approaches used in this study yielded consistent results, which revealed a high degree of heterogeneity among strains and detection of two distinct genetic groups.Key words: rhizobia, diversity, salinity, RAPD, PCR-RFLP.}, journal={Canadian Journal of Microbiology}, year={2001}, month={Feb} }
 @article{isolation and characterization of two genetically distant groups of acetobacter diazotrophicus from a new host plant eleusine coracana l._1999, url={http://dx.doi.org/10.1046/j.1365-2672.1999.00804.x}, DOI={10.1046/j.1365-2672.1999.00804.x}, abstractNote={Acetobacter diazotrophicus strains were isolated from Eleusine coracana, a new host plant cultivated along the coast of Tamil Nadu in India. Using a species‐specific oligonucleotide primer and PCR amplification, the presence of this bacterium was demonstrated directly in plant tissues, proving its endophytic nature, and it was absent in non‐rhizosphere soils. The isolates were also characterized on the basis of typical morphology, electron microscopy and biochemical tests, including nitrogen‐fixing efficiency, to assess their diversity. When RAPD analysis was performed on the isolates, they fell into two distinct genetically related groups when compared with the type strain PA1 5 (ATCC 49037). In view of the importance of E. coracana to this region, associated nitrogen‐fixing Acetobacter strains may be agronomically important because they could supply part of the nitrogen that the crop requires.}, journal={Journal of Applied Microbiology}, year={1999}, month={Jul} }
 @article{competitiveness of native bradyrhizobium japonicum strains in two different soil types_1997, url={http://dx.doi.org/10.1007/s003740050315}, DOI={10.1007/s003740050315}, journal={Biology and Fertility of Soils}, year={1997}, month={Sep} }
 @article{phylogenetic grouping and identification of rhizobium isolates on the basis of random amplified polymorphic dna profiles_1993, url={http://dx.doi.org/10.1139/m93-096}, DOI={10.1139/m93-096}, abstractNote={ Through the use of a single, random 15mer as a primer, between 1 and 12 DNA amplification products were obtained per strain from a selection of 84 Rhizobium and Bradyrhizobium isolates. A principal-coordinate analysis was used to analyse the resulting amplified DNA profiles and it was possible to assign isolates to specific groupings. Within the species Rhizobium leguminosarum, the biovar phaseoli formed a distinct group from the other biovars of the species, viciae and trifolii, which grouped together. Isolates of Rhizobium meliloti and Bradyrhizobium species formed their own clear, specific groups. Although it was possible to identify individual isolates on the basis of differences in their amplified DNA profiles, there was evidence that some amplified segments were conserved among individuals at the biovar and species levels.Key words: Rhizobium, DNA amplification, random primers. }, journal={Canadian Journal of Microbiology}, year={1993}, month={Jul} }