Ehrlichia ewingii infection in white-tailed deer (Odocoileus virginianus).
Two closely related zoonotic ehrlichiae, Ehrlichia chaffeensis and E. ewingii, are transmitted by Amblyomma americanum, the lone star tick. Because white-tailed deer (Odocoileus virginianus) are critical hosts for all mobile stages of A. americanum and are important vertebrate reservoirs of E. chaffeensis, we investigated whether deer may be infected with E. ewingii, a cause of granulocytotropic ehrlichiosis in humans and dogs. To test for E. ewingii infection, we used polymerase chain reaction and inoculation of fawns with whole blood from wild deer. Of 110 deer tested from 20 locations in 8 U.S. states, 6 (5.5%) were positive for E. ewingii. In addition, natural E. ewingii infection was confirmed through infection of captive fawns. These findings expand the geographic distribution of E. ewingii, along with risk for human infection, to include areas of Kentucky, Georgia, and South Carolina. These data suggest that white-tailed deer may be an important reservoir for E. ewingii.
Yabsley
Michael J
MJ
Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, 30602, USA. myabsley@vet.uga.edu
Varela
Andrea S
AS
Tate
Cynthia M
CM
Dugan
Vivien G
VG
Stallknecht
David E
DE
Little
Susan E
SE
Davidson
William R
WR
D000818:Animals; D003670:Deer / Q000097:blood / Q000382:microbiology*; D004197:Disease Reservoirs; D004536:Ehrlichia / Q000302:isolation & purification*; D016873:Ehrlichiosis / Q000097:blood / Q000635:transmission*; D006801:Humans; D016133:Polymerase Chain Reaction; D012698:Serologic Tests; D015144:Southeastern United States