ARS | Publication request: Epizootic Hemorrhagic Disease Outbreak in a Captive Facility Housing White-tailed Deer (Odocoileus Virginianus), Bison (Bison Bison), Elk (Cervus Elaphus), Cattle (Bos Taurus) and Goats (Capra Hircus) in Colorado

Submitted to: Journal of Zoo and Wildlife Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 9, 2010
Publication Date: N/A

Interpretive Summary: In the early fall of 2007 deer on a captive wildlife research facility in Fort Collins, Colorado experienced died from epizootic hemorrhagic disease virus. Molecular techniques were used to detect and identify virus from dead animals. Virus was later isolated from the lungs and spleen of 2 dead deer. Antibodies were detected in bison, elk, domestic cattle, and domestic goats housed on the site before the outbreak but postoutbreak the number of animals with antibodies generally went out. Two elk lost neutralizing antibodies over the time course of pre to post outbreak. No clinical signs were noted in the bison, cattle, or goats during the outbreak. One elk became clinically ill but etiology could not be established. Although experimental EHDV infections have been reported in bison and elk, natural exposures have not been previously documented in these species in North America. The roles that elk, bison, cattle, and goats might play in the epidemiology of EHDV in a close-contact multispecies situation remain unknown.

Technical Abstract: A captive wildlife research facility in Fort Collins, Colorado experienced mortality in white-tailed deer (Odocoileus virginianus) due to epizootic hemorrhagic disease virus (EHDV) infection in late summer and early fall of 2007. RNA from EHDV was amplified by RT-PCR from the spleen and lung tissues of 2 white-tailed deer with >99% similarity to previously sequenced isolates of EHDV-2 and identical to each other. In addition, EHDV was isolated on CPAE cells from the spleens of these 2 deer. Pre- and postoutbreak sera from other species maintained in the same facility, including bison (Bison bison), elk (Cervus elaphus), domestic cattle (Bos taurus), and domestic goats (Capra hircus), as well as postoutbreak sera from the surviving deer were assayed by virus neutralization. Preoutbreak sera from 3 elk and 1 cow and postoutbreak sera from 7 goats, 1 deer, 2 elk, 3 bison, and 2 cattle neutralized EHDV-2 in all four-virus neutralization replicates. Preoutbreak sera from 9 goats, 4 bison, and 1 cow and postoutbreak sera from an additional 3 goats, 3 elk, and a deer neutralized EHDV-1. These were not the same animals that neutralized EHDV-2. Two elk lost neutralizing antibodies over the time course. No clinical signs were noted in the bison, cattle, or goats during the outbreak. One elk became clinically ill but etiology could not be established. Although experimental EHDV infections have been reported in bison and elk, natural exposures have not been previously documented in these species in North America. The roles that elk, bison, cattle, and goats might play in the epidemiology of EHDV in a close-contact multispecies situation remain unknown.