Iowa Horse Owners Encouraged to Vaccinated Against WNV

Iowa Horse Owners Encouraged to Vaccinated Against WNV

Photo: Erica Larson, News Editor

On June 6, Iowa Secretary of Agriculture Bill Northey encouraged horse owners to protect their animals from the West Nile virus (WNV) by ensuring their horses are properly vaccinated against the disease.

“As we enter mosquito season it is important for horse owners to vaccinate their animals so that they are protected from West Nile virus,” Northey said. “I encourage owners to talk to their veterinarian about vaccination and make sure all their animals’ vaccinations are up-to-date.”

The first year of vaccination requires two inoculations to be protective for horses and then annual boosters in following years. In 2012 Iowa had 36 confirmed WNV cases in horses; In most instances the animals had not been vaccinated and in a cases the horse had only received their first vaccine dose. Iowa had only one confirmed case in a horse in 2011.

West Nile virus has been a problem in the United States since 1999, and while it is primarily a disease of birds it can infect horses, dogs, humans, and several other animal species. It is transmitted by the bite of an infected mosquito. Clinical signs for WNV in horses include flulike signs, where the horse seems mildly anorexic and depressed; fine and coarse muscle and skin fasciculation (twitching); hyperesthesia (hypersensitivity to touch and sound); changes in mentation (mentality), when horses look like they are daydreaming or "just not with it"; occasional somnolence (drowsiness); propulsive walking (driving or pushing forward, often without control); and "spinal" signs, including asymmetrical weakness. Some horses show asymmetrical or symmetrical ataxia. Equine mortality rate can be as high as 30-40%.

Horse owners are encouraged to contact their veterinarian for more information and to discuss vaccination and other preventions measures, such as mosquito control.

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