A new emergency rule was approved Aug. 1 by Colorado animal health authorities related to livestock movement and vesicular stomatitis.

"New Mexico is currently experiencing a significant outbreak of vesicular stomatitis (VS). VS is classified as a Foreign Animal Disease (FAD), and, as such, cases are required to be reported nationally and internationally,” the published rule states. "To minimize the spread of the disease and to help avoid severe restrictions on future livestock movement, the following requirements and restrictions are being implemented. For livestock events held in N.M., the event coordinator is responsible for helping ensure livestock owners’ compliance with these and any other livestock movement requirements as it applies to animals admitted onto the premises of the event and will go away in 90 days."

In Texas, a similar rule applies to the movement of New Mexico livestock across state lines.

“Where out-of-state livestock are part of a public event such as roping, racing, breeding or other forms of public exhibition or traveling interstate, a health certificate (CVI) written within 5 days of entering the show will be required for all New Mexico origin livestock.

According to the published Texas rule, the following statement is to appear on the CVI:

"The animals represented on this certificate have not originated from a premises or area under quarantine for vesicular stomatitis (VS), or a premises on which VS has been diagnosed in the past 21 days. I have examined these animals and have not observed lesions or clinical signs of VS."

The Texas Animal Health Commission (TAHC) prohibits entry of animals from VS quarantined premises and also requires livestock to be accompanied by a valid certificate of veterinary inspection. After confirmation of VS in Colorado, TAHC officials encourage livestock owners to use the best means possible to limit exposure of their livestock to insect bites.

Similar rules have been issued by Arizona, Oklahoma and 31 other states and Canada.

Vesicular stomatitis is a viral disease that primarily affects horses and cattle and occasionally swine, sheep, goats, llamas, and alpacas. Humans can also become infected with the disease when handling affected animals, but this is a rare event. Vesicular stomatitis has been confirmed only in the Western Hemisphere. It is known to be an endemic disease in the warmer regions of North, Central, and South America, but outbreaks of the disease in other temperate geographic parts of the hemisphere occur sporadically.

In the past decade, the Southwestern and Western United States have experienced a number of VS outbreaks. Outbreaks usually occur during the warmer months, often along waterways.