Pigeon Fever in the area

A friend sent me this email and I think this is the kind of information we can all use. If you come across something that you think would be of interest to the horse community, send it along and we'll get it out.


I just got a call from my shoer telling me that there have been cases of pigeon fever reported in Clark County horses - a handful of cases here in the Camas/Washougal area for sure. It is not usually fatal but I did look it up on line and here is the deal -

FORT COLLINS - Equine veterinarians at Colorado State University's James L. Voss Veterinary Teaching Hospital report a serious increase in the number of cases of pigeon fever they have treated since early fall and warn horse owners to be alert for signs of the highly contagious disease.

Seventy-six cases from Colorado's Front Range have been confirmed by the Colorado State University Veterinary Diagnostic Laboratory since early fall, more than six times the number of cases from last year's total of 12 confirmed cases and far above the seven confirmed cases in 2000.

"What was once considered a disease of California horses is now a growing problem for the Colorado equine population," said Andrea Torres, veterinarian and microbiology resident who conducted a study of the disease in Colorado in 2000-2001. "The increased number of confirmed cases may be due to a more educated horse-owning public and/or to more veterinarians being aware of the disease and testing for it."

Torres and other veterinarians at the hospital point out that the signs of pigeon fever can also initially resemble those of other diseases such as strangles. Sometimes the only initial signs are lameness and a reluctance to move.

Pigeon fever, also called pigeon breast, breastbone fever, false strangles, dryland strangles or dryland distemper, is caused by Corynebacterium pseudotuberculosis and is found worldwide. It can strike a horse of any age, sex or breed, but usually attacks young adult animals. There is a low incidence in foals.

It has also been diagnosed in cattle, and a similar disease affects sheep and goats. The disease is not transmissible to humans, although humans can carry the infectious agent on shoes, clothing, hands or barn tools and transfer it to another animal.

Clinical signs include lameness, fever, lethargy and weight loss and usually is accompanied by very deep abscesses and multiple sores along the chest, midline and groin area and, sometimes, the back. Abscesses also can develop internally.

The disease is called pigeon fever because infected animals often develop abscesses in their pectoral muscles, which swell and resemble a pigeon's chest. Although the disease is considered seasonal, with most cases occurring in early fall, a number of cases have been confirmed during winter months and other times of the year as well.

The causative bacteria live in the soil and can enter the animal's body through wounds, broken skin or through mucous membranes. Additionally, some researchers believe pigeon fever may be transmitted by flies.

The disease occurs in three forms: external abscesses, internal abscesses and limb infection, also known as ulcerative lymphangitis. The most common forms are external abscess and lymphangitis, with the prognosis of a full recovery being generally good. Internal abscesses are much more difficult to treat.

"Because this disease is so highly contagious, it is very important that veterinarians accurately diagnose these cases to tailor treatment and control," said Torres.

"Horse owners should be aware of the clinical signs and understand that veterinary care must be timely. Infected horses should be isolated, the abscesses properly treated and the drainage properly disposed of. The area where the infected horse is kept must be properly cleaned and completely disinfected because this is a very hardy bacterium. Pest control is extremely important"

You can read the rest of this story including an extensive fact sheet about Pigeon Fever on this Colorado State web page.