Deer & Ehrlichia
Clin Diagn Lab Immunol. 1998 November; 5(6): 762–765.
Copyright © 1998, American Society for Microbiology
Serologic Evidence of a Natural Infection of White-Tailed Deer with the Agent of Human Granulocytic Ehrlichiosis in Wisconsin and Maryland
Jennifer J. Walls,1 Kristin M. Asanovich,2 Johan S. Bakken,3and J. Stephen Dumler1,2*
Department of Pathology, University of Maryland School of Medicine,1 and Division of Medical Microbiology, Department of Pathology, The Johns Hopkins University School of Medicine,2 Baltimore, Maryland, and SMDC Health System, Duluth, Minnesota3
*Corresponding author. Mailing address: Division of Medical Microbiology, Department of Pathology, The Johns Hopkins University School of Medicine, Meyer B1-193, 600 N. Wolfe St., Baltimore, MD 21287. Phone: (410) 955-5077. Fax: (410) 614-8087. E-mail: email@example.com.
Received May 29, 1998; Revisions requested July 15, 1998; Accepted August 10, 1998.
This article has been cited by other articles in PMC.
White-tailed deer participate in the maintenance of the Ixodes tick life cycle and are reservoirs for some tick-borne infectious agents. Deer may be useful sentinels for tick-transmitted agents, such as ehrlichiae. In order to determine whether white-tailed deer are markers of natural transmission or are reservoirs for the human granulocytic ehrlichiosis (HGE) agent, we performed indirect immunofluorescent-antibody (IFA) tests and immunoblotting with the HGE agent and Ehrlichia chaffeensison sera from 43 and 294 deer captured in northwest Wisconsin during 1994 and 1995, respectively, and 12 deer from southern Maryland.
According to IFA testing, 47% of 1994 Wisconsin sera, 60% of 1995 Wisconsin sera, and 25% of Maryland sera contained HGE agent antibodies. All IFA-positive deer sera tested reacted with the 44-kDa band which is unique to the Ehrlichia phagocytophila group.
Serologic reactions to E. chaffeensis were detected by IFA testing in 15 of 337 (4%) Wisconsin deer and in 10 of 12 (83%) Maryland deer, while 60 and 80% of E. chaffeensis IFA-positive Wisconsin and Maryland deer sera, respectively, reacted with the E. chaffeensis 28- to 29-kDa antigens by immunoblotting.
A total of 4% of deer from Wisconsin and 25% of deer from Maryland were found by IFA testing to have antibodies to both the HGE agent and E. chaffeensis; 75% of these were confirmed to containE. chaffeensis antibodies by immunoblotting.
These results suggest that white-tailed deer in diverse geographical regions of the United States are naturally infected with the HGE agent, E. chaffeensis, or both and that these animals, and potentially humans, are exposed to infected ticks at a high frequency in nature.