Last month, the AZHS and local veterinarians released news that two new strains of distemper may be developing in the United States. The Arizona Humane Society issued a public health warning, which can be viewed here.

However, the AVMA states that this information is not entirely accurate. According to data from the Cornell Animal Health Diagnostic Center and the University of Wisconsin School of Veterinary Medicine’s Department of Pathobiological Sciences, there is no basis to the rumor that two new strains of distemper have developed in the areas of Arizona.

Genetic studies of the canine distemper viruses in the US do show strains that have previously gone undetected, however it is unknown if these strains are newly arrived or just now being seen due to better testing protocols and equipment.

The organizations also make it clear that “a genetic change in the virus doesn’t necessarily change the virus enough to impact our pet’s health.”

There has been an increase in the frequency of distemper cases through the Southwest, but authorities now believe this could be due to the earlier arrival of warm weather. Normally, the virus affects young, unvaccinated puppies every spring.  But this year, the Arizona Humane Society has noticed a difference in the disease. Both puppies and adult dogs with questionable vaccination histories appear to be at high risk for the disease. Authorities believe that a down economy and fewer owners obtaining vaccinations for their pets could be contributing to the problem.

Regardless of whether or not there are new strains, there has been an unusually large number of cases in the Southwest and it is strongly recommended that your pets are current on all of their vaccinations. The available distemper vaccines are highly effective and will protect your pet in all but rare circumstances. 

For more information on vaccinations, check out the American Animal Hospital Association’s Canine Vaccine Guidelines.