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Serving: MN
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FATAL DISEASE: Eastern equine encephalitis, which is spread by mosquitoes, can cause fatal infections in horses and people. EEE is fatal in horses in more than 90% of cases. Clinical signs include fever, lethargy, not eating and walking aimlessly.

Equine virus found in deceased Aitkin County horse

Mosquitoes that carry eastern equine encephalitis can bite and infect people as well as horses.

A seven-year-old crossbred gelding horse in Aitkin County died and was confirmed in early September to have had eastern equine encephalitis.

The Minnesota Department of Health reported the EEE-positive results to the Minnesota Board of Animal Health and also reported the animal was negative for other diseases of concern including rabies, western equine encephalitis and West Nile virus encephalitis.

Before the horse died, it was showing clinical signs of neurologic disease including staggering, impaired vision and excessive drooling. Samples were initially submitted to the University of Minnesota Veterinary Diagnostic Laboratory for rabies testing. The rabies samples were negative and additional tests were ordered for the other diseases.

The horse had no history of travel over the past three months and a reported last vaccination for EEE 18 months ago. At least 11 other horses remaining on the premises appear healthy at this time and have subsequently received initial vaccinations for EEE, WEE and WNV with boosters pending.

Brian Hoefs, MBAH senior veterinarian, says vaccination and decreasing exposure to mosquitoes can help protect horses against the diseases.

“While COVID-19 has restricted many equine related activities, it is imperative to be vigilant about annual preventative care, including core vaccinations,” he says. “We encourage all horse owners to work with their veterinarians to develop strategies for preventing EEE/WEE/WNV exposure and illness in their horses.”

EEE can cause fatal infections in horses and people. The virus is primarily transmitted by mosquitoes. Horses and people are considered “dead end hosts” meaning they are unable to transmit the disease to other horses or people. In horses, EEE is fatal in more than 90% of cases. Clinical signs include fever, lethargy, not eating and walking aimlessly.

Even though people cannot contract the disease from horses, cases in horses are a clear indication that infected mosquitoes are in the area and can infect humans. Clinical signs of EEE in people can include high fever, muscle pain, altered mental status, headache, photophobia and seizures, which occur between three and 10 days after the bite of an infected mosquito. Consult your healthcare provider for additional information about EEE in people.

Source: The Minnesota Board of Animal Health, which is solely responsible for the information provided and is wholly owned by the source. Informa Business Media and all of its subsidiaries are not responsible for any of the content contained in this information asset.
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