Equine disease outbreaks in North America

Multiple equine disease outbreaks have been reported across North America. In late August, Washington reported a case of strangles in King County, prompting a self-imposed quarantine at a private facility. Simultaneously, the USDA identified presumptive positive cases of vesicular stomatitis (VSV) in Colorado, specifically in La Plata and Montezuma counties. This contributed to a total of 45 VSV-affected premises identified across Arizona, Colorado, and New Mexico, all involving the vesicular stomatitis New Jersey virus serotype.

By early September, reports of strangles expanded to Florida and Ontario, Canada. Florida officials confirmed two cases in Highlands and Levy counties, marking the 21st and 22nd confirmed cases in the state for 2026. In Ontario, a four-month-old colt in Grey County tested positive for the bacterial infection. On September 1, the Florida Department of Agriculture and Consumer Services reported a strangles infection at a private facility in Marion County, where one horse tested positive and seventeen others were exposed.

On September 8, new strangles cases were confirmed in Washington and Wisconsin. In Whatcom County, Washington, a horse transported from Texas tested positive; the animal is recovering while two other horses exposed at the private farm are under quarantine. In Dane County, Wisconsin, a 13-year-old Quarter Horse gelding at a boarding facility tested positive after exhibiting fever, cough, and nasal discharge. The horse is currently in recovery.