Site-specific geographic association between Amblyomma americanum (Acari: Ixodidae) infestations and Ehrlichia chaffeensis-reactive (Rickettsiales: Ehrlichieae) antibodies in white-tailed deer.
Serum samples from white-tailed deer, Odocoileus virginianus Zimmermann, collected from 1982 through 1992 from the southeastern United States were tested for antibodies reactive to Ehrlichia chaffeensis Anderson, Dawson, Jones, & Wilson, the causative agent of human ehrlichiosis. Results were compared between areas based on known infestations of the lone star tick, Amblyomma americanum L., a suspected vector of E. chaffeensis. One hundred and twenty-five of 300 (41.7%) deer tested positive (> or = 1:128) for E. chaffeensis-reactive antibodies by fluorescent antibody analysis. Thirty of 30 (100%) collection areas known to be lone star tick infested contained deer that tested positive for E. chaffeensis-reactive antibodies, corresponding to 121/150 (80.7%) of deer examined. A few deer, 4/150 (2.7%) of those examined, from 2 of 30 (6.7%) areas where lone star ticks were not detected were positive for E. chaffeensis-reactive antibodies. This site-specific geographic association between A. americanum and the presence of E. chaffeensis-reactive antibodies in deer provides strong evidence that A. americanum is a natural vector of E. chaffeensis or a closely related species among white-tailed deer.
Lockhart
J M
JM
Southeastern Cooperative Wildlife Disease Study, Department of Veterinary Parasitology, University of Georgia, Athens 30602, USA.
Davidson
W R
WR
Stallknecht
D E
DE
Dawson
J E
JE
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology*; D001096:Arachnid Vectors; D003670:Deer / Q000382:microbiology / Q000469:parasitology; D018469:Ehrlichia chaffeensis / Q000276:immunology*; D016873:Ehrlichiosis / Q000097:blood / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D005843:Geography; D012189:Retrospective Studies; D013984:Tick Infestations / Q000469:parasitology* / Q000662:veterinary; D013987:Ticks
D000907:Antibodies, Bacterial