{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T06:09:43Z","timestamp":1783577383775,"version":"3.55.0"},"reference-count":40,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,7,2]],"date-time":"2022-07-02T00:00:00Z","timestamp":1656720000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NIH, National Institute of Allergy and Infectious Diseases","award":["1R03AI166406-01"],"award-info":[{"award-number":["1R03AI166406-01"]}]},{"name":"Southeast Center for Agricultural Health and Injury Prevention (SCAHIP)","award":["1R03AI166406-01"],"award-info":[{"award-number":["1R03AI166406-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Chiggers are vectors of rickettsial pathogenic bacteria, Orientia spp., that cause the human disease, scrub typhus, in the Asian\u2013Pacific 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.<\/jats:p>","DOI":"10.3390\/microorganisms10071342","type":"journal-article","created":{"date-parts":[[2022,7,3]],"date-time":"2022-07-03T22:50:46Z","timestamp":1656888646000},"page":"1342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Rickettsia felis and Other Rickettsia Species in Chigger Mites Collected from Wild Rodents in North Carolina, USA"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0700-4472","authenticated-orcid":false,"given":"Loganathan","family":"Ponnusamy","sequence":"first","affiliation":[{"name":"Department of Entomology and Plant Pathology, Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reuben","family":"Garshong","sequence":"additional","affiliation":[{"name":"Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1293-5298","authenticated-orcid":false,"given":"Bryan S.","family":"McLean","sequence":"additional","affiliation":[{"name":"Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gideon","family":"Wasserberg","sequence":"additional","affiliation":[{"name":"Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lance A.","family":"Durden","sequence":"additional","affiliation":[{"name":"Department of Biology, Georgia Southern University, 4324 Old Register Road Statesboro, Statesboro, GA 30458, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dac","family":"Crossley","sequence":"additional","affiliation":[{"name":"Georgia Museum of Natural History, Natural History Building, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles S.","family":"Apperson","sequence":"additional","affiliation":[{"name":"Department of Entomology and Plant Pathology, Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6386-0994","authenticated-orcid":false,"given":"R. Michael","family":"Roe","sequence":"additional","affiliation":[{"name":"Department of Entomology and Plant Pathology, Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1097\/00001432-200310000-00009","article-title":"Scrub typhus and tropical rickettsioses","volume":"16","author":"Watt","year":"2003","journal-title":"Curr. Opin. Infect. Dis."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1862","DOI":"10.1093\/cid\/ciab748","article-title":"Novel vector of scrub typhus in sub-Antarctic Chile: Evidence from human exposure","volume":"74","author":"Weitzel","year":"2022","journal-title":"Clin. Infect. Dis."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Xu, G., Walker, D.H., Jupiter, D., Melby, P.C., and Arcari, C.M. 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