RALEIGH – It’s the beginning of mosquito season in North Carolina, which means it’s also time for equine owners to talk to their veterinarians about vaccinating animals against mosquito-borne diseases.
West Nile Virus and Eastern Equine Encephalomyelitis are endemic across North Carolina and can cause illness or death in equine, but can be prevented with a sequence of two vaccines. Last year, there were two reported cases of WNV and 13 cases of EEE, but veterinarians expect that the actual number is higher.
“Now is the time to vaccinate against West Nile Virus and EEE,” state veterinarian David Marshall said. “Mosquito breeding peaks in August, so starting the vaccination protocol now gives it time to take effect.”
The EEE and WNV vaccinations initially require two shots, three to four weeks apart, for horses, mules and donkeys that have no prior vaccination history. Neither vaccination fully protects the animal until several weeks after the second shot, so it is best to vaccinate as early in the mosquito season as possible. Marshall encourages horse owners to talk to their veterinarians about maintaining the vaccination year-round in North Carolina, since the mosquito season is long.
“In addition to getting animals vaccinated, everyone needs to be extra vigilant now to reduce the breeding grounds for mosquitoes,” Marshall said. “Take the time now to rid your yard and pasture of any standing water to reduce the risk.”
Symptoms of EEE in equine include impaired vision, aimless wandering, head pressing, circling, inability to swallow, irregular staggering gait, paralysis, convulsions and death.
Symptoms of WNV in horses can include loss of appetite and depression, fever, weakness or paralysis of hind limbs, convulsions, impaired vision or hyperexcitability.
People, horses and birds can become infected from a mosquito carrying the diseases, but there is no evidence that horses can transmit the virus to other horses, birds or people through direct contact.