Equine Encephalitis Circulating, Horse Dies: Orange County Officials

ORANGE COUNTY, NY — A local horse has died from Eastern Equine Encephalitis virus, which is considered one of the most serious mosquito-borne disease in the United States because of its high mortality rate — and Orange County officials have put out an alert.

The horse had not been vaccinated for EEE and did not travel outside of the county, county officials said Friday.

The diagnosis means EEEv is circulating among mosquitos that bite mammals, including humans, health officials said. All suspected cases of viral encephalitis should be reported immediately by calling 845-291-2330.

“In Orange County, equestrian sports and activities have become extremely popular with residents and visitors, so keeping our horses and the people who interact with them safe and healthy is a priority,” said County Executive Steve Neuhaus. “I encourage all residents to follow our Health Department’s recommendations to avoid being bitten by mosquitoes.”

EEE is less common than West Nile Virus but far more severe. It causes encephalitis, or inflammation of the brain. Symptoms typically appear four to 10 days after a bite from an infected mosquito and can include sudden onset of headache, high fever, chills, and vomiting. The disease can progress to disorientation, seizures, and coma. People over 50 and younger than age 15 are at greatest risk for severe cases.

EEE has a higher fatality rate compared to WNV, with about one out of three infected people dying, and many survivors experiencing mild to severe long-term brain damage.

Similar to WNV, EEE is transmitted by mosquitoes that have fed on infected birds. However, EEE is more likely to affect horses and humans in regions with specific mosquito species capable of spreading the virus.

“Until we have a hard frost, people in all areas of Orange County need to fully protect themselves from mosquito bites when they’re outdoors,” said OCDOH Health Commissioner Dr. Alicia Pointer

Prevention: The Three "M"s

• Minimize Exposure: Avoid outdoor activities during dawn and dusk when mosquitoes are most active. Repair or replace window and door screens to keep mosquitoes outside. Wear long sleeves and pants, use mosquito repellents, and ensure your living spaces are secure against mosquitoes.
• Mosquito Repellent: Use EPA-registered insect repellents with DEET, picaridin, or other effective ingredients. Always follow the product label instructions.
• Manage Environment: Dispose of old tires, tin cans, ceramic pots, or other water-holding containers. Mosquitoes can breed in something as small as a discarded bottle cap. Clear roof gutters and be sure they drain properly. Turn over wheelbarrows, wading pools and outdoor toys when not in use. Clean and chlorinate swimming pools, outdoor saunas, hot tubs, and drain pool covers. Change the water in birdbaths and horse troughs twice a week. Remove leaf debris from yards and gardens and clean vegetation and debris from the edge of ponds.

READ: More on Protection Against Eastern Equine Encephalitis

“We will keep you updated on our social media pages and the OCDOH webpage while we continue to work closely with the NYSDOH, which provides support and guidance," Pointer said.

Local health care providers should consider mosquito-borne diseases, including EEEv, in the differential diagnosis of any patient with clinical evidence of encephalitis or meningitis, county officials said.