The Canadian Food Inspection Agency (CFIA) has confirmed that the Vesicular Stomatitis (VS) outbreak in New Mexico has been resolved, and that all restrictions governing horses entering Canada from that state have been lifted.

VS was detected in two New Mexico horses on April 20, 2012. These cases were the first confirmed diagnosis of active VS in the United States since 2010. Additional VS diagnoses were made in the state of Colorado in October 2012.

In the wake of the initial detection, the CFIA took immediate action to safeguard Canada against an outbreak of VS. Therefore, import and export restrictions were implemented in regards to horses entering Canada from the state of New Mexico, and the return of Canadian horses who were in New Mexico at the time of the outbreak, or thereafter. Similar restrictions were later enforced concerning the state of Colorado, but were lifted in October 2012 once the outbreak was resolved.

Now that the outbreak in New Mexico has also been resolved, there are currently no VS-related import restrictions concerning Canada and the U.S. The restrictions governing horses from and travelling in or through Colorado were lifted previously.

The last recorded case of VS within Canada was in 1949. However, VS is a reportable disease as per the CFIA, meaning that horse owners must report any suspected cases of VS immediately. Symptoms include blister-like lesions on the inside of the mouth, nose, and hooves, as well as flu-like symptoms and anorexia.

VS is a viral disease that primarily affects cattle, horses, and swine, and occasionally goats and sheep. Humans are also vulnerable to the disease, and can become infected through contact with affected animals.

The conditions which allow VS to spread are not fully known. However, the primary forms of contraction are thought to be insect vectors, mechanical transmission, and movement of animals. Animals generally recover within two weeks. Once the disease is present within a herd, it moves from animal to animal through direct physical contact, or exposure to saliva or fluid from ruptured lesions or through indirect contact.

Historically, VS outbreaks tend to occur in the southwestern U.S. during warm seasons, and are especially likely in places close to river ways. Outbreaks can be sporadic and unpredictable. The only way to distinguish VS from other diseases with similar symptoms (including foot-and-mouth disease) in livestock other than horses is through laboratory tests. (Source: USDA)