As of late October, all vesicular stomatitis quarantines in Texas had been lifted; however, quarantines remained at 141 premises in Colorado and 38 in New Mexico.
The tristate outbreak, which began in Texas in May, is the first vesicular stomatitis outbreak in the United States since 1998. Over the course of the outbreak, there have been more than 400 confirmed cases in horses, cattle, and other ruminants and at least 246 premises quarantined in the three states.
Vesicular stomatitis outbreaks occur periodically in the United States. The disease can cause great concern when livestock are affected because its clinical signs mimic those of foot-and-mouth disease in susceptible species, and FMD has not been seen in the United States since 1929. Horses are not susceptible to FMD, so that was ruled out in the cases involving horses. However, when cattle, pigs, sheep, or other cloven-hooved animals develop signs such as sores and blisters, laboratory tests must be performed to differentiate between the two diseases.
More information about vesicular stomatitis is available at the USDA Animal and Plant Health Inspection Service's Web site, www.aphis.usda.gov/lpa/issues/vs/vs.html.