Epizootic Hemorrhagic Disease Virus: An outbreak of Cattle Herds in South Dakota

Epizootic hemorrhagic disease (EHD) is an arthropod-borne viral disease that is transmitted through Culicoides sp. This is the first report of an outbreak of EHD in a wide geographic region of the upper Midwest that involved at least 80 different farms. Herds affected had a wide range of disease from no signs, minor hemorrhaging of mouth, udder erythmea, swelling of coronary bands, lameness to reports of mortality, yet however approximately for every 100 cow/calf pair there was 3 clinical EHD infections. Findings from both the phone survey and serological studies reinforced that the age of cow could be dependent factor for both symptoms of EHD and seroconversion. Other factors that showed a strong possibly in aiding the spread of EHDV is temperatures both spring and summer, biosecurity practices of cattle producers, co-mingling between cattle and white-tailed deer, and vector control. Further studies are needed as the number of Orbivirus infections increase and the range of the serotypes are spreading in the US. Orbiviruses continue to pose a risk to the cattle industry through trade barriers but also now through the occurrence of clinical disease