Mad cow identified in American dairy animal

The case of American mad cow disease reported Tuesday by the Department of Agriculture was the first in six years. Agriculture Secretary Tom Vilsack maintained that the California dairy cow was never introduced into the food supply, either human or animal.

The infection was discovered during routine, random testing mandated by the USDA. The variant of mad cow disease—technically called Bovine Spongiform Encephalopathy (BSE)—was found to be atypical, which means that the cow did not contract the disease from contaminated feed. Such infections can occur spontaneously, epidemiologist Guy Loneragan told Bloomberg.

The finding has caught the attention of consumer advocacy groups, such as Consumers Union. Michael Hanson, a scientist on staff at the Yonkers-based organization, criticized the USDA’s inspection regime, likening it to Russian Roulette and calling for an expanded national testing program.

Meanwhile, lawmakers and industry groups maintain that, in the words of National Cattlemen’s Beef Association chairman Tom Talbot, “All US beef is safe.”

While only Indonesia has banned the sale of US beef in response to the discovery, other trading partners are expected to remain vigilant.

America’s first case of mad cow disease was reported in 2003. The beef industry suffered tremendous losses as other nations forbade the import of US beef, and major corporations like Tyson Foods and Cargill sustained billions of dollars in losses in the years that followed.

The full report from Bloomberg can be found here.

Coming as it does on the heels of the “pink slime” fiasco, the finding could have done significant further damage to America’s beef industry. But the markets do not appear to have experienced a dramatic swing as a result, according to the Associate Press, noting that futures recovered on Wednesday after a sharp drop the day before.

The reason for such grave concern over mad cow disease lies in the enigmatic pathogen responsible for the illness. Mad cow is a neurological disease caused by abnormal prions—a form of normal protein that has undergone a change in shape such that it damages and ultimately kills nerve cells. The function of a protein is determined by its shape; in prion diseases, misshapen proteins turn on the body, destroying nerve tissue. To complicate matters further, the prions are able to propagate, and to spread from one organism to another, thus the concern regarding the use of infected tissue in cattle feed—and human food products.

Prion diseases are not confined to cows. In sheep, the disease is known as “scrapie,” owing to the way in which infected sheep rub their sides against tree trunks and fence posts, causing skin damage. In humans, the disease is called Creutzfeldt-Jakob Disease (CJD). CJD is a rare condition, with a worldwide incidence of one in a million; however, the symptoms are clearly-defined. The progression from early behavioral changes to full-fledged dementia is relatively rapid. No treatment exists and death is virtually certain, occurring an average of seven months after the onset of the disease.

Consuming food infected with prions has been tied to a condition termed variant CJD, or vCJD. The symptoms are similar in most respects to ordinary CJD, with the notable exception that it afflicts young adults as well as the elderly, behavioral disruptions are more pronounced, and the progression of the illness is slower.

Because the disease is both incurable and fatal, extreme precautions have to be taken in order to safeguard consumers against contaminated products. This includes, among other measures, regulations against the use of nerve tissue in human-grade food. While it is encouraging that the discovery of an infected cow appears to be an isolated case, it would be a grave mistake to become complacent.