According to Texas Animal Health Commission (TAHC) officials, a small beef herd in South Texas (Starr County) has been determined to be infected. Brucellosis is a bacterial disease of cattle that can cause abortions, weak calves and low milk production. Humans can also catch brucellosis (undulant fever), most commonly by consuming unpasteurized milk products, or handling contaminated birthing material when assisting with difficult calving situations in infected cows.
Routine surveillance (blood testing) at a livestock market led to the discovery of the infected herd. TAHC rules require all adult sexually intact cattle to be tested negative for the disease prior to change of ownership. “This herd may have been affected for some time and not detected due to lack of sales of adult test eligible cattle,” said Dr. Andy Schwartz, TAHC state epidemiologist. For that reason a full disease investigation is underway to find the possible source of infection, and to identify any exposed animals that may have left the herd. Though it has been five years since cattle brucellosis was last detected in Texas, there was ongoing concern among industry and regulatory officials that infected herds might still exist. “The discovery of this herd is a reminder of the value of continued surveillance efforts, and the importance of an effective system for tracing exposed animals,” added Dr. Schwartz.
The federal brucellosis eradication program began in earnest in 1959, with Texas being the last state to be declared “free” of the disease in 2008. The good news is that Texas will not lose its Class Free status as designated by the United States Department of Agriculture (USDA). USDA issued an interim rule in 2010 that suspended the provision for possible reclassification of any Class Free State or area to a lower status, and instead encouraged a localized risk based disease management approach. Currently, the only known reservoir for bovine brucellosis in the United States is the Greater Yellowstone Area (GYA) located in parts of Montana, Idaho and Wyoming. The GYA is not considered the likely source of the newly detected Texas herd, however, based upon the epidemiological information received to date.