@article{cave_richardson_chen_watson_roe_2023, title={Acaricidal Biominerals and Mode-of-Action Studies against Adult Blacklegged Ticks, Ixodes scapularis}, volume={11}, ISSN={["2076-2607"]}, url={https://www.mdpi.com/2076-2607/11/8/1906}, DOI={10.3390/microorganisms11081906}, abstractNote={Ticks in the USA are the most important arthropod vector of microbes that cause human and animal disease. The blacklegged tick, Ixodes scapularis, the focus of this study, is able to transmit the bacteria that causes Lyme disease in humans in the USA. The main approach to tick control is the use of chemical acaricides and repellents, but known and potential tick resistance to these chemicals requires the discovery of new methods of control. Volcanic glass, Imergard, was recently developed to mimic the insecticide mode of action of the minerals from diatoms (diatomaceous earth, DE) for the control of malaria mosquitoes in Africa. However, studies on the use of these minerals for tick control are minimal. In a dipping assay, which was put into DE (Celite), the times of 50 and 90% death of adult female I. scapularis were 7.3 and 10.5 h, respectively. Our mimic of DE, Imergard, killed ticks in 6.7 and 11.2 h, respectively. In a choice-mortality assay, ticks moved onto a treated surface of Imergard and died at 11.2 and 15.8 h, respectively. Ticks had greater locomotor activity before death when treated by dipping for both Imergard and Celite versus the no-mineral control. The ticks after making contact with Imergard had the mineral covering most of their body surface shown by scanning electron microscopy with evidence of Imergard inside their respiratory system. Although the assumed mode of action of Imergard and Celite is dehydration, the minerals are not hygroscopic, there was no evidence of cuticle damage, and death occurred in as little as 2 h, suggesting minimal abrasive action of the cuticle. Semi-field and field studies are needed in the future to examine the practical use of Imergard and Celite for tick control, and studies need to examine their effect on tick breathing and respiratory retention of water.}, number={8}, journal={MICROORGANISMS}, author={Cave, Grayson L. and Richardson, Elise A. and Chen, Kaiying and Watson, David W. and Roe, R. Michael}, year={2023}, month={Aug} }
 @article{chen_deguenon_lawrie_roe_2023, title={Biomolecular Minerals and Volcanic Glass Bio-Mimics to Control Adult Sand Flies, the Vector of Human Leishmania Protozoan Parasites}, volume={13}, ISSN={["2218-273X"]}, url={https://www.mdpi.com/2218-273X/13/8/1235}, DOI={10.3390/biom13081235}, abstractNote={Sand flies (Diptera: Psychodidae) serve as vectors for transmitting protozoan parasites, Leishmania spp., that cause the disease called leishmaniasis. The main approach to controlling sand flies is the use of chemical insecticides. The discovery of alternative methods for their control is needed because of potential health risks of chemical insecticides and development of sand fly resistance to these pesticides. The biomineral produced by diatoms (diatomaceous earth, DE; Celite) and a volcanic glass bio-mimic (Imergard) have been shown by our group to be efficacious against mosquitoes, filth flies, and ticks but never studied for the control of sand flies. In a modified World Health Organization cone test, 50% of adult Phlebotomus papatasi sand flies at 29 ± 1 °C, 55 ± 5% RH, and 12:12 LD, when exposed to Imergard and Celite, were dead in 13.08 and 7.57 h, respectively. Proof of concept was established for the use of these biominerals for sand fly and leishmaniasis disease control. Using a light source as an attractant to the minerals had no significant effect on the LT50, the time to 50% mortality. The LT50 at a higher relative humidity of 70 ± 5% increased to 20.91 and 20.56 h for Imergard and Celite, respectively, suggesting their mode of action was dehydration. Scanning electron microscopy of dead sand flies showed high coating levels of Celite only on the sides of the thorax and on the tarsi, suggesting an alternative mode of action for mechanical insecticides.}, number={8}, journal={BIOMOLECULES}, author={Chen, Kaiying and Deguenon, Jean Marcel and Lawrie, Roger D. and Roe, R. Michael}, year={2023}, month={Aug} }
 @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} }
 @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://www.mdpi.com/1660-4601/19/22/15147}, 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{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{deguenon_riegel_cloherty-duvernay_chen_stewart_wang_gittins_tihomirov_apperson_mccord_et al._2021, title={New Mosquitocide Derived From Volcanic Rock}, volume={58}, ISSN={["1938-2928"]}, DOI={10.1093/jme/tjaa141}, abstractNote={Abstract}, number={1}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Deguenon, Jean M. and Riegel, Claudia and Cloherty-Duvernay, Erin R. and Chen, Kaiying and Stewart, David A. and Wang, Bo and Gittins, David and Tihomirov, Larissa and Apperson, Charles S. and McCord, Marian G. and et al.}, year={2021}, month={Jan}, pages={458–464} }
 @article{chen_deguenon_cave_denning_reiskind_watson_stewart_gittins_zheng_liu_et al._2021, title={New thinking for filth fly control: residual, non-chemical wall spray from volcanic glass}, volume={35}, ISSN={["1365-2915"]}, DOI={10.1111/mve.12521}, abstractNote={Abstract}, number={3}, journal={MEDICAL AND VETERINARY ENTOMOLOGY}, author={Chen, K. and Deguenon, J. M. and Cave, G. and Denning, S. S. and Reiskind, M. H. and Watson, D. W. and Stewart, D. A. and Gittins, D. and Zheng, Y. and Liu, X. and et al.}, year={2021}, month={Sep}, pages={451–461} }