The year’s first reported New Jersey case of Eastern Equine Encephalitis (EEE), a serious, mosquito-borne illness, was found in a mare vaccinated against the disease in April. The mare, who was about 12 years old, was euthanized this week.
“Horse owners need to be vigilant in vaccinating their animals against diseases spread by mosquitoes,” state Secretary of Agriculture Douglas Fisher said. “Vaccinated animals are much less likely to contract deadly diseases such as EEE and West Nile Virus.”
Unfortunately, that was not the situation with the mare in this case. 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 horses’ 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 considered to be “dead-end” hosts for the virus.
In 2018, New Jersey had five cases of EEE and one case of West Nile.