Low Prevalence of Antibodies to Bluetongue and Epizootic Hemorrhagic Disease Viruses in Dogs from Southern Georgia

Abstract

Bluetongue viruses (BTV) and epizootic hemorrhagic disease viruses (EHDV) are closely related orbivirus serogroups that infect both wild and domestic ruminants; both virus groups are vector-borne by Culicoides spp. 5 Although it is generally thought that these viruses cause disease in artiodactyls only, abortion and death due to BTV serotype 11 infection was recently reported in domestic dogs following vaccination with a contaminated modified live combination canine vaccine. 1,2 Dogs also are susceptible to African horsesickness viruses (AHSV), 3,9 another serogroup of orbiviruses. Although a high prevalence of antibodies to EHDV and BTV occurs in white-tailed deer (WTD, Odocoileus virginianus) in the southeastern United States, especially in the coastal plain, 6 little information is available regarding natural exposure of nonartiodacty ls such as dogs. In such an area, dogs might be naturally exposed to these viruses, either by vector transmission or, as in the case of AHSV, 9 through consumption of infected meat. The purpose of this study was to determine prevalence of antibodies to BTV and EHDV in dogs from the coastal plain of Georgia. Dog serum samples used in this study were from a larger randomized sample that was collected at veterinary clinics throughout Georgia from April 1992 to March 1993. Randomization was accomplished by requesting the participating veterinarians to obtain a blood sample from the first 4 dogs that entered the clinic on alternate Mondays. All samples selected for this study were from dogs from the coastal plain of Georgia; efforts were made to select dogs that were primarily outside dwellers. The following information was recorded for most of the dogs sampled: county of residence, age, sex, breed, and number of hours inside and outside. All samples were stored at -80 C until testing. Serum samples were tested for precipitating antibodies to BTV and/or EHDV serogroups using EHDV and BTV agar gel immunodiffusion (AGID) test kits a