Favorable drought conditions could trigger "pigeon fever" outbreak in horses, officials warn

The Texas Animal Health Commission (TAHC) recently released an update on "pigeon fever," otherwise known as dry-land distemper or dry-land strangles, in response to an increase in calls and questions about the disease. "Pigeon fever," which causes abscesses and swelling in a horse's pectoral region, is caused by the bacteria Corynebacterium pseudotuberculosis. The disease is most commonly seen in dry areas of the western United States but can be found in other parts of the country as well if conditions are favorable.

With Texas experiencing its most expensive drought in history in 2011, the number of "pigeon fever" cases rose substantially last year, the TAHC says. The Texas Veterinary Medical Diagnostic Laboratory obtained more than 350 positive cultures for the disease-causing bacteria in 2011 compared with fewer than 100 cases each year from 2005 to 2010. Additionally, the Veterinary Medical Teaching Hospital at Texas A&M diagnosed more than four times as many cases in 2011 compared with 2010.

The outbreak of cases last year has been attributed to the fact that C. pseudotuberculosis thrives in dry soil. Flies carry the disease and are crucial to transmission, says the TAHC, so fly control is critical to disease prevention. The TAHC also states that basic sanitation is of paramount importance in reducing the spread of disease and recommends that horse owners and veterinarians take measures to isolate affected horses and dispose of abscess drainage properly. Any visible wounds should be treated promptly, as they can quickly become contaminated with flies and dirt. Because of the infectious nature of this disease, the TAHC is encouraging horse owners to call their veterinarian immediately at the first sign of illness.