Your Guide to Equine Health Care

West Nile Virus Reported in Horses Nationwide

According to data from the U.S. Department of Agriculture, 64 cases of WNV have been confirmed in 23 states.

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As autumn approaches, some owners are ready to start thinking about phoning their veterinarians to set up their horses’ fall vaccinations. And because the number of West Nile virus (WNV) cases confirmed in U.S. horses continues to rise slowly, consider requesting a WNV booster.

According to preliminary data released Sept. 5 by the U.S. Department of Agriculture Animal Health Monitoring and Surveillance, 64 cases of WNV have been confirmed in 23 states thus far in 2013. Some recently confirmed cases include:

California—As of Aug. 16, the California Department of Food and Agriculture (CDFA) reported that two additional horses in that state had tested positive for WNV. The affected horses are "a 1-year-old unvaccinated Andalusian colt in Sacramento County and a 4-year-old Morgan mare of unknown vaccination status in Placer County. Both horses are recovering."

The CDFA’s statement also indicated that a total of eight horses have been confirmed positive for WNV in 2013. They were located in Kern, Placer, Riverside, Sacramento (3), and Stanislaus (2) Counties. Four of those were

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Written by:

Erica Larson, former news editor for The Horse, holds a degree in journalism with an external specialty in equine science from Michigan State University in East Lansing. A Massachusetts native, she grew up in the saddle and has dabbled in a variety of disciplines including foxhunting, saddle seat, and mounted games. Currently, Erica competes in eventing with her OTTB, Dorado.

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