Salem County Horse Contracts Eastern Equine Encephalitis: Second Case in New Jersey for 2024

A Salem County horse has become the second confirmed case of the mosquito-borne disease in the state this year, underscoring the importance of vaccination for equine protection.

NEW JERSEY – A horse in Salem County has been confirmed as the second case of Eastern Equine Encephalitis (EEE) in New Jersey in 2024. The elderly, unvaccinated gelding exhibited symptoms including fever, ataxia (loss of coordination) in both the front and rear limbs, and an inability to stand. Due to the severity of the illness, the horse was euthanized on September 4, 2024.

EEE, a mosquito-borne virus that causes inflammation of the brain, is often fatal in horses, posing a higher risk of death than West Nile Virus (WNV). Both diseases are transmitted by mosquitoes, with birds serving as the primary hosts. Horses and humans are considered "dead-end" hosts, meaning they do not contribute to further transmission of the virus.

The New Jersey Department of Agriculture’s Animal Health Diagnostic Laboratory confirmed the EEE diagnosis through testing. The horse had no recent travel history, indicating local transmission of the virus.

Mosquitoes carrying the EEE virus have been detected in several counties, including Cape May, Gloucester, Camden, Hunterdon, Monmouth, Morris, and Union. With mosquito populations hovering near the five-year average in most regions, livestock owners are strongly advised to vaccinate their animals against both EEE and WNV. Vaccines for both diseases are commercially available and effective in preventing infection.

This is the second reported case of EEE in New Jersey horses this year, with the first occurring in Atlantic County. EEE and WNV must be reported to the State Veterinarian within 48 hours of diagnosis.

For more information on EEE, horse owners can visit the New Jersey Department of Agriculture's website, or contact the NJ Animal Health Diagnostic Laboratory for assistance with testing.