OKLAHOMA CITY, Okla. — The Oklahoma Department of Agriculture, Food and Forestry is encouraging horse owners across the state to take precautions against West Nile Virus, Eastern Equine Encephalitis, and other common diseases by vaccinating their horses. 

WNV and EEE are zoonotic diseases spread by mosquitoes and thought to cycle between mosquitoes and birds. Mosquitoes contract the virus from birds and then spread it to mammals (and reptiles) — most commonly humans and horses. Late summer and early fall are the times of year we see the most cases in Oklahoma. 

There are multiple vaccination options available; please visit with your veterinarian to determine which vaccination option best fits your operation. Infected horses can become anorexic, depressed and show neurologic signs or behavior changes. The incubation period in horses is between three and 15 days. Many infected horses are asymptomatic. Clinical signs can be similar to those seen with other neurologic diseases including rabies and can result in death. 

Oklahomans can reduce the risk of both EEE and WNV by eliminating standing water, which serves as a breeding area for mosquitos. Disease risk can be reduced by limiting exposure to mosquitoes with these common practices: 

  • Changing horses’ drinking water regularly 
  • Mowing tall grass 
  • Draining stagnant water 
  • Maintaining screens 
  • Installing fans at horse stables 
  • Using insect repellants on both horses and people 
  • Keeping horses indoors during these high mosquito-feeding times of dawn and dusk 

ODAFF also recommends vaccinating horses against Equine Herpes Virus and Equine Influenza. Vaccinations for Tetanus and Rabies are vital for horses, as they do not need to be around other horses to be susceptible to these diseases and can be fatal. 

ODAFF asks horse owners and event managers remain at a heightened level of awareness, implement biosecurity practices to minimize potential exposure, and consult with a veterinarian on an appropriate vaccination schedule. Please ensure to report any suspicious illness or neurologic disease to state officials as soon as it is discovered by calling the state veterinarians office at (405) 522-0270.