If you’re in an area with warming weather trends, diseases that were previously considered rare may suddenly appear on your radar. Recently, a pigeon fever outbreak in Missouri had veterinarians and disease specialists more than a little concerned.
Previously, cases of pigeon fever had been few and far between in the state, which has a continental climate— cold winters and hot and humid summers. Not ideal for pigeon fever.
“Before the summer of 2012, I personally had seen only two confirmed cases in Missouri,” says Philip Johnson, BVSc, MS, MRCVS, DACVIM, of the University of Missouri. “That summer we saw a handful of cases at the university teaching hospital and heard about many more in the field in Missouri.”
Pigeon fever, caused by Corynebacterium pseudotuberculosis, is most often seen in hot, dry climates like that of California, New Mexico, Colorado and Texas. Signs of the disease include painful swelling, abscesses and inflammation in the legs, chest and abdominal cavities. But the outbreak in Missouri wasn’t entirely a mystery.
“There was a severe drought that summer,” says Johnson, “followed by wet weather in the fall—these weather conditions are favorable to pigeon fever. I suspect this disease will be more common in Missouri and other Midwestern states from here on out.”
There is no vaccine for pigeon fever, but if spring and summer are becoming warmer in your area and mosquitoes and other disease-carrying insects enjoy a longer active season, don’t be surprised if your veterinarian suggests adding one or two vaccines to your horse’s regimen. In addition to the “core” vaccinations—against tetanus, eastern/western equine encephalomyelitis, West Nile virus and rabies—that are recommended for all horses, your veterinarian may determine that your horse now needs protection against other viral or bacterial diseases.
And, of course, your veterinarian is your first and best resource when it comes to disease outbreaks in your area. Don’t rely on the rumor mill or social media for information. Consider bookmarking your state veterinarian’s office or your state department of agriculture to get accurate and up-to-date information. Another good resource is the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service at www.aphis.usda.gov.