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 su...