Another case of the mosquito-borne disease called Eastern equine encephalitis (EEE) has been confirmed in Wisconsin, this time in a horse in Polk County. This latest confirmation is prompting another warning from the Wisconsin State Veterinarian’s office and a health advisory from the Wisconsin Department of Health Services.

Blood samples from a Quarter Horse were submitted to Wisconsin Veterinary Diagnostic Laboratory on Aug. 30 and confirmed Sept. 2.

State Veterinarian Robert Ehlenfeldt, DVM, issued the first warning Aug. 21 after the office received notification that two horses in Clark and Lincoln Counties had been sickened with EEE. 

"Vaccinate your horses if you haven’t already, or get boosters for those you vaccinated earlier in the year," says Assistant State Veterinarian Paul McGraw, DVM. "EEE has a mortality rate in excess of 90%. The vaccine is not expensive, it’s effective, and if we’ve found EEE in these three counties, it’s reasonable to assume it’s more widespread. Unless we have a really early killing frost, we still have a lot of mosquito season ahead of us