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September 13, 2018
PO Box 330
Trenton, New Jersey 08625-0330

Jeff Wolfe
P: (609) 633-2954
C: (609) 433-1785

First West Nile Virus, Fourth EEE Cases for New Jersey in 2018

(TRENTON) – A 10-year old Burlington County mare is the first reported case of West Nile Virus (WNV) and an Ocean County gelding is the fourth reported case of Eastern Equine Encephalitis (EEE), each serious, mosquito-borne illnesses in horses, in New Jersey for 2018.  Neither horse had been vaccinated against WNV or EEE in 2018. The Burlington County horse is undergoing treatment while the Ocean County horse was euthanized on September 4, 2018. The other three EEE cases in 2018, all euthanized, were in Monmouth and Camden counties.

EEE causes inflammation of the brain tissue and has a significantly higher risk of death in horses than West Nile Virus infection. West Nile Virus is a viral disease that affects a horse’s neurological system. The disease is transmitted by a mosquito bite. The virus cycles between birds and mosquitoes with horses and humans being incidental hosts. EEE infections in horses are not a significant risk factor for human infection because horses (like humans) are "dead-end" hosts for the virus.

“We continue to encourage horse owners be vigilant in vaccinating their animals against these diseases spread by mosquitoes,” New Jersey Secretary of Agriculture Douglas H. Fisher said. “Vaccinated animals are much less likely to contract deadly diseases such as EEE and West Nile Virus.”

With the higher than average number of mosquitos this season ( and a 40 percent increase in WNV positive mosquitoes ( compared to 2017, livestock owners are strongly encouraged to vaccinate against WNV,  EEE and other mosquito-borne diseases. Effective equine vaccines for EEE and WNV are available commercially. Horse owners should contact their veterinarians if their horses are not up-to-date on their vaccinations against both EEE and WNV.

For more information about EEE in horses, visit the New Jersey Department of Agriculture web site at:

EEE and West Nile virus, like other viral diseases affecting a horse’s neurological system, must be reported to the state veterinarian at 609-671-6400 within 48 hours of diagnosis. The New Jersey Animal Health Diagnostic Laboratory is available to assist with EEE and WNV testing and can be reached at 609-406-6999 or via email – Learn more about the NJ Animal Health Diagnostic lab at


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