Wisconsin Confirms Third EEE Case of 2017

Wisconsin Confirms Third EEE Case of 2017

A viral disease, EEE affects the central nervous system and is transmitted to horses by infected mosquitoes.

Photo: iStock

The Equine Disease Communication Center (EDCC) reported Aug. 15 that a third Wisconsin horse has tested positive for Eastern equine encephalitis (EEE).

“The horse was an unvaccinated 9-year-old Quarter Horse mare from Monroe County,” the EDCC said on its website. “The horse acted depressed during the afternoon of Aug. 6, then began showing neurologic signs and was down by that evening. She was euthanized the next day.”

All three equine EEE cases confirmed in Wisconsin this year have been in Monroe County horses, the EDCC said.

A viral disease, EEE affects the central nervous system and is transmitted to horses by infected mosquitoes. Clinical signs of EEE include moderate to high fever, depression, lack of appetite, cranial nerve deficits (facial paralysis, tongue weakness, difficulty swallowing), behavioral changes (aggression, self-mutilation, or drowsiness), gait abnormalities, or severe central nervous system signs, such as head-pressing, circling, blindness, and seizures. The course of EEE can be swift, with death occurring two to three days after onset of clinical signs despite intensive care. Horses that survive might have long-lasting impairments and neurologic problems.

Health Alert: EEE, WEE, VEE

Horses that have not already been vaccinated this year for EEE or other mosquito-borne diseases are at greater risk, but it is not too late to vaccinate. Horses that have been vaccinated in past years will need an annual booster shot; in areas with a long mosquito season, veterinarians might recommend two boosters per year—one in the spring and one in the fall. However, if an owner did not vaccinate their animal in previous years, the horse will need the two-shot vaccination series within a three- to six-week period.

In addition to vaccinations, horse owners also need to reduce the mosquito populations and their possible breeding areas. Recommendations include removing stagnant water sources, keeping animals inside during the bugs’ feeding times, which are typically early in the morning and evening, and using mosquito repellents.

About the Author

Erica Larson, News Editor

Erica Larson, news editor, holds a degree in journalism with an external specialty in equine science from Michigan State University in East Lansing. A Massachusetts native, she grew up in the saddle and has dabbled in a variety of disciplines including foxhunting, saddle seat, and mounted games. Currently, Erica competes in eventing with her OTTB, Dorado.

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