Equine Disease Communication Center has reported two new cases of West Nile virus (WNV) in horses.
In Adams County, Indiana, a 5-year-old Standardbred mare tested positive for WNV on Sept. 18. The mare was not vaccinated and showed gait abnormalities on Sept. 13, which worsened to recumbency by Sept. 15, leading to her being euthanized.
In Box Elder County, Utah, another horse tested positive for WNV, but no further details are available at this time.
EDCC Health Watch, a program by Equine Network, utilizes information from the Equine Disease Communication Center (EDCC) to provide verified equine disease reports. The EDCC is a nonprofit organization supported by industry donations to offer accessible infectious disease information.
WNV 101
West Nile virus is transmitted to horses through mosquito bites. Symptoms may include flulike signs, muscle twitching, hypersensitivity, changes in mentation, drowsiness, propulsive walking, and spinal signs.
- Flulike signs
- Muscle and skin fasciculation
- Hyperesthesia
- Changes in mentation
- Drowsiness
- Propulsive walking
- Spinal signs
There is no cure for WNV in horses, and mortality rates can be as high as 30-40%. Vaccination is key for prevention, with annual boosters recommended for previously vaccinated horses and a two-shot series for unvaccinated horses.
In addition to vaccinations, owners should take steps to reduce mosquito populations and limit horse exposure to mosquitoes by removing stagnant water sources, cleaning water buckets regularly, keeping horses indoors during peak mosquito times, and using approved mosquito repellents for horses.