Upstate New York Confirms Another Eastern Equine Encephalitis Case

Madison County Public Health (MCPH) recently announced its first recorded human case of eastern equine encephalitis (EEE) in Madison County, New York.

On September 22, 2025, MCPH stated in a press release that it had been notified of a confirmed case in a Madison County resident by the Wadsworth Center and is currently investigating. The individual is currently hospitalized for EEE infection.

This disease is often fatal (30%), and many patients who survive EEE experience neurologic impairment.

"Temperatures are getting cooler, and although we are seeing a significant decrease in mosquitoes, they remain not only a nuisance, but a potential health threat. Residents should continue to take steps to prevent mosquito bites to reduce the risk of mosquito-borne disease infection," MCPH Director Eric Faisst stated.

In July 2025, the New York State Department of Health notified MCPH of a mosquito pool that tested positive for EEE. From 1971 through 2024, 12 individuals in New York were diagnosed with EEEV; seven of them died.

About one year ago, a Ulster County resident died following an EEE infection.

This is concerning news since Madison County is located adjacent to Syracuse, New York, which has a population of over 600,000.

EEE is a rare but severe viral disease spread by infected mosquitoes that can affect people and horses. People of all ages are susceptible to infection. While most people bitten by an infected mosquito will not develop symptoms, severe cases may begin with the sudden onset of headache, high fever, chills, and vomiting.

There is no commercially available human vaccine or treatment for EEE. The best protection is to prevent mosquito bites, says MCPH.