It’s a disease with an almost unbelievable fatality rate of 80-90 percent and one that has now claimed its first victim of 2018 in Virginia.
Eastern Equine Encephalitis is spread to horses via the bite of an infected mosquito – something that can be found in excess in Hampton Roads this year. The Virginia Department of Agriculture and Consumer Services reported last Friday that a Quarter Horse mare from Suffolk entered the North Carolina State Veterinary School Hospital in late July and subsequently died.
Eastern Equine Encephalitis is also sometimes referred to as the sleeping sickness and can cause inflammation or swelling of the brain and spinal cord.
Symptoms infected horses might show include impaired vision, aimless wandering, head pressing, circling, an inability to swallow, irregular staggering gait, paralysis and convulsions.
Once a horse has been bitten by an infected mosquito, it usually takes three-to-10 days for symptoms to appear.
The weather has provided nearly perfect conditions for the disease-carrying mosquitoes, and horses are at risk of contracting mosquito-borne diseases such as EEE and West Nile virus, said Dr. Charles Broaddus, state veterinarian with VDACS, adding that if a horse hasn’t been vaccinated, now is the time to do so.
“Both the WNV and EEE vaccine are highly effective in minimizing disease, if given appropriately,” he said.
The vaccines are effective for six to 12 months, so most owners must revaccinate at least annually, but in areas where the disease occurs frequently, every six months.
For the vaccine to be effective, it must be given at least two weeks before the horse is exposed to the virus. To stimulate full immunity, horses must be vaccinated twice, about 30 days apart, during the first year of vaccination.
The horse in Suffolk was vaccinated incompletely, receiving an initial vaccination but not the follow-up shot.
Horse owners can find more information on how to control mosquitoes around horses online, and they may also contact VDACS’ Office of the State Veterinarian at 804-692-0601 or consult their local veterinarian.
Information about EEE can also be found online or by calling the VDACS Office of Veterinary Services at 804-786-2483