The mosquito-borne disease called Eastern equine encephalitis, or EEE, has been diagnosed in two horses in two adjacent north central Wisconsin counties, prompting a second warning from the Wisconsin State Veterinarian.

Blood samples from a 7-year-old American Quarter Horse in Price County and a 6-year-old Belgian mare in Taylor County were submitted to Wisconsin Veterinary Diagnostic Laboratory Aug. 11 and Aug. 12, respectively. Both showed signs of neurological disease, and neither had been vaccinated for EEE. It is not known whether the horses survived.

"Vaccinate your horses if you haven’t already, or get boosters for those you vaccinated earlier in the year," said state veterinarian Robert Ehlenfeldt, DVM. "EEE has a mortality rate in excess of 90% (in horses). 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."

Ehlenfeldt issued his first warning Aug. 9, after his office received notification that two llamas in Dunn County had died from EEE and a horse on the same farm had been sickened