In a surprising twist, Wisconsin’s dairy cows in Waukesha County have been found infected with a viral disease predominantly affecting deer populations. State authorities have confirmed the presence of Epizootic Hemorrhagic Disease (EHD) in dairy cattle, marking a rare occurrence of the disease crossing over to livestock.
According to the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP), the discovery was made in cows that were not producing milk. EHD, a viral infection spread by midges, typically emerges during late summer and early fall. While its presence in deer is somewhat routine, it’s unusual for cattle to contract the disease.
“EHD does not infect humans, and generally causes mild or inapparent infections in domestic cattle and small ruminants,” highlighted the Cornell University’s Wildlife Health Lab. This reassurance is echoed by DATCP, which confirmed that humans face no risk from insect bites or consuming products from infected animals.
Though cattle rarely show symptoms, infected individuals may suffer from lameness, weight loss, fever, or sores. “There is no treatment for EHD,” DATCP stated, emphasizing the virus’s persistence in the environment. Wisconsin previously recorded a cattle case in 2013.
DNR reports ongoing outbreak in deer
Contrary to its rarity in cattle, EHD is widespread among deer in Wisconsin. The Department of Natural Resources (DNR) reported active outbreaks in Washington and Waukesha counties, with Washington experiencing over 1,200 cases and Waukesha around 400. Other counties, including Dodge and Milwaukee, have reported suspected cases.
The DNR notes that Wisconsin is on the northern edge of the fly’s habitat, leading to sporadic outbreaks. Deer affected by EHD might exhibit foaming around the mouth and nose, weakness, and a tendency to lie in water to combat fever. While the virus does not persist in carcasses, the DNR advises against handling them due to other potential disease risks.
With the onset of the first freeze, the number of infecting insects is expected to decline, reducing new cases. State officials urge those observing symptoms in cattle or farm-raised deer to consult veterinarians promptly. Reporting EHD cases to DATCP within 10 days is mandatory.
Attention to parasite control and avoiding overcrowding are recommended for cattle and deer herders to mitigate the spread of this disease.
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