California Now Reports Seven Equine WNV Cases With Five Deaths

The sixth and seventh equine WNV cases in California this year were in San Joaquin and Glenn Counties.

The sixth and seventh cases of equine West Nile virus (WNV) have been confirmed in California. The California Department of Food and Agriculture (CDFA) reported on August 18 that an unvaccinated Warmblood yearling filly in San Joaquin County was displaying severe neurologic signs and was confirmed positive for WNV. Due to the severity of her clinical signs, the filly was euthanized.

A 3-year-old Appaloosa gelding of unknown vaccination status in Glenn County also was displaying neurologic signs. The gelding has been treated and is recovering. 

The CDFA stated that for 2017, a total of seven horses have been confirmed positive for WNV. The positive horses were located in Glenn, Contra Costa, Fresno, Kern (2), Riverside and San Joaquin Counties. Five horses were unvaccinated and two horses had unknown vaccination status. Five horses died or were euthanized and two horses are recovering.

CDFA continually monitors and investigates equine neurologic cases for the presence of WNV in California. CDFA urges horse owners to consult their veterinarian concerning a WNV vaccination program to ensure maximum protection of their horses.

For more information visit the CDFA website at

This article was created with information from the Equine Disease Communication Center (EDCC). The EDCC works to protect horses and the horse industry from the threat of infectious diseases in North America. The communication system is designed to seek and report real time information about disease outbreaks similar to how the Centers for Disease Control and Prevention (CDC) alerts the human population about diseases in people.

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