Recently, a mare in Ocean County, NJ was diagnosed with 2019’s first case of Eastern Equine Encephalitis in the state. While the horse had been vaccinated in 2019, veterinarians advice regular vaccination in high risk areas, as well as at the start of the mosquito season to reduce chances of your horse contracting the disease. Eastern Equine Encephalitis is especially concerning as it has a much higher fatality rate than West Nile Virus and in 2018, the state of New Jersey had five cases of EEE compared to just one of West Nile. However, it’s important to note that both diseases are transmitted via mosquitoes and quite dangerous.

The best course of action is to speak with your veterinarian about the risks your horses face, any history of the disease in your area, and if you plan to travel to an area where cases have been reported. Vaccinations for most mosquito borne illnesses can be boostered prior to any increased risk, so it’s always best to consult with your veterinarian before traveling or when there’s a high risk in your immediate area.

The New Jersey Department of Agriculture has additional information on equine diseases here. Risks for equine diseases in summer go beyond just weather and insects such as mosquitos or ticks, but also due to the fact that many people travel with their horses more during the warmer months. This can make the spread of diseases from horse to horse easier as more equines are on the road in multiple locations than in colder months. It is worth noting, however that transmission from horse to horse directly is not possible with EEE or West Nile Virus, when there is increased mosquito activity, a mosquito biting an infected horse can then potentially carry the virus to other horses in the area. While it is not a common occurrence and usually the virus passes from birds to mosquitoes to horses, there are exceptions. As per the NJ Department of Agriculture fact sheet about EEE, Horses, humans and other mammals are generally considered to be incidental (dead end) hosts for EEEV, but some horses develop a transient viremia sufficient to infect mosquitoes, and horse to horse transmission has been demonstrated by this route in the laboratory. Similar information is available about West Nile Virus, which is why vaccination is so important.

You can read the full story on the EEE case in New Jersey here:

Read up on the American Association of Equine Practitioner’s guidelines for equine vaccination and speak with your vet to determine the best course of action to ensure your horse is protected. Have questions? We make farm calls and are here to help. Contact us to set up your horse’s appointment today.