{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,6]],"date-time":"2026-09-06T05:12:18Z","timestamp":1788671538664,"version":"build-2803163510"},"reference-count":23,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T00:00:00Z","timestamp":1788480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000030","name":"Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["U01CK000661"],"award-info":[{"award-number":["U01CK000661"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["NU51CK000372"],"award-info":[{"award-number":["NU51CK000372"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004878","name":"MassWildlife","doi-asserted-by":"crossref","award":["USFWS F22AF03624-00 W35R"],"award-info":[{"award-number":["USFWS F22AF03624-00 W35R"]}],"id":[{"id":"10.13039\/100004878","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100004878","name":"MassWildlife","doi-asserted-by":"crossref","award":["USFWS F23AP01478-00"],"award-info":[{"award-number":["USFWS F23AP01478-00"]}],"id":[{"id":"10.13039\/100004878","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Anaplasma phagocytophilum is a tick-borne bacterium and the causative agent of human granulocytic anaplasmosis. Two major variants have been identified in North America: a human pathogenic variant (Ap-ha) that is maintained by small mammals and a nonpathogenic variant (Ap-v1) that is maintained by white-tailed deer (Odocoileus virginianus). Despite white-tailed deer being recognized as the main reservoir of Ap-v1, few studies have directly demonstrated transmission of Ap-v1 from white-tailed deer to feeding I. scapularis ticks, and transmission to feeding larvae remains undescribed. In this study, we collected samples from an outdoor white-tailed deer research facility during an I. scapularis larval questing season in the eastern United States to investigate the variants infecting white-tailed deer and acquisition by feeding larvae. Although both variants were present in questing ticks onsite, white-tailed deer were persistently infected with only Ap-v1 and transferred this variant to feeding I. scapularis larvae with high efficiency. These results support the concept that white-tailed deer play a role in the maintenance of Ap-v1 in nature and highlight the utility of captive white-tailed deer research facilities for studying vector\u2013pathogen\u2013host biology.<\/jats:p>","DOI":"10.3390\/pathogens15090933","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T13:50:44Z","timestamp":1788529844000},"page":"933","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Anaplasma phagocytophilum Variant 1 from White-Tailed Deer (Odocoileus virginianus) in Feeding Ixodes scapularis Larvae"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5899-8529","authenticated-orcid":false,"given":"Patrick","family":"Pearson","sequence":"first","affiliation":[{"name":"Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA"},{"name":"New England Center of Excellence in Vector-Borne Diseases (NEWVEC), University of Massachusetts, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mileena","family":"Ryan","sequence":"additional","affiliation":[{"name":"Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA"},{"name":"New England Center of Excellence in Vector-Borne Diseases (NEWVEC), University of Massachusetts, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martha B.","family":"Leo","sequence":"additional","affiliation":[{"name":"Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA"},{"name":"New England Center of Excellence in Vector-Borne Diseases (NEWVEC), University of Massachusetts, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5240-9276","authenticated-orcid":false,"given":"Guang","family":"Xu","sequence":"additional","affiliation":[{"name":"Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA"},{"name":"New England Center of Excellence in Vector-Borne Diseases (NEWVEC), University of Massachusetts, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-0387-9879","authenticated-orcid":false,"given":"Martin J. R.","family":"Feehan","sequence":"additional","affiliation":[{"name":"Massachusetts Division of Fisheries and Wildlife, Westborough, MA 01581, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dowd","family":"Naik","sequence":"additional","affiliation":[{"name":"Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY 12237, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6538-623X","authenticated-orcid":false,"given":"Melissa A.","family":"Prusinski","sequence":"additional","affiliation":[{"name":"Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY 12237, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7175-6380","authenticated-orcid":false,"given":"Stephen M.","family":"Rich","sequence":"additional","affiliation":[{"name":"Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA"},{"name":"New England Center of Excellence in Vector-Borne Diseases (NEWVEC), University of Massachusetts, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"341","DOI":"10.1016\/j.idc.2015.02.007","article-title":"Human Granulocytic Anaplasmosis","volume":"29","author":"Bakken","year":"2015","journal-title":"Infect. 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