The Tennessee Department of Agriculture has reported that a horse in Washington County has tested positive for West Nile virus (WNV).
EDCC Health Watch is a marketing program by Equine Network that uses information from the Equine Disease Communication Center (EDCC) to create and share verified equine disease reports. The EDCC is a nonprofit organization supported by industry donations to provide open access to infectious disease information.
WNV 101
West Nile virus is transmitted to horses through bites from infected mosquitoes. While not all infected horses show symptoms, those that do may display:
- Flulike signs such as mild anorexia and depression;
- Muscle and skin twitching;
- Hypersensitivity to touch and sound;
- Changes in mental activity;
- Drowsiness;
- Propulsive walking;
- Spinal signs like weakness or ataxia.
There is no cure for West Nile virus, but some horses can recover with supportive care. Mortality rates in horses can be as high as 30-40%.
Research has shown that vaccines are effective in preventing WNV. Horses that have been vaccinated before need an annual booster shot, while unvaccinated horses may require a two-shot series over a few weeks. It takes time for horses to develop immunity after vaccination.
In addition to vaccinations, horse owners can reduce the risk of WNV by managing mosquito populations and limiting exposure by:
- Eliminating stagnant water;
- Cleaning and refilling water sources regularly;
- Keeping horses indoors during peak mosquito times;
- Using approved mosquito repellents for horses.