By Miriam Raftery

July 12, 2023 (San Diego’s East County) – The  Vesicular Stomatitis Virus (VSV) outbreak in livestock that began in San Diego County in May has now spread to encompass six California counties.  One county in Texas also had a single confirmed case on a property that’s been released from quarantine.

Species affected locally includes primarily equine species such as horses, though two local sites have had cattle infected and one San Diego location has had clinically infected rhinoceros.

Disease can affect all hooved livestock and can also spread to humans

By Miriam Raftery

May 22, 2023 (San Diego) – Fifteen properties in San Diego County are under quarantine by the U.S. Department of Agriculture, after six cases of Vesicular Stomatitis Virus (VSV) have been confirmed in San Diego County and testing is underway on another nine suspected local cases, according to the USDA website on the disease. There are also two confirmed cases and two suspected cases in Riverside County, where four properties are quarantined.  These are the only areas in the U.S. with current cases of VSV.

 The first local case in this outbreak occurred May 17 in Ramona, according to the San Diego Union-Tribune. While all of the local cases so far are in horses, the disease can also afflict donkeys, cattle, pigs, sheep, goats, llamas, alpacas or other hooved livestock.

The quarantines will  last at least 14 days after the last known case.  However blisters on mouths and hooves can take up to two months to resolve.The quarantines mean no transporting animals to or from the impacted properties will be allowed until a veterinarian has cleared animals for travel.  Some states and livestock events such as horse shows may prohibit animals from the impacted areas from participating even if there is no known exposure, so check with show organizers before traveling to any livestock even