Last week the United States Department of Agriculture (USDA) reported a case of atypical bovine spongiform encephalopathy (BSE), popularly known as mad cow disease, in a California dairy cow. According to USDA Chief Veterinary Officer John Clifford, the cow was “never presented for slaughter for human consumption, so at no time presented a risk to the food supply or human health.” There was also no threat from the cow’s milk because milk does not transmit mad cow disease.
The good news is that this particular animal was identified and immediately removed from the food supply. The USDA is quick to point out its success in this matter and highlight the dramatic reductions in cases of mad cow disease worldwide — in 2011 there were 29 cases of the disease among cattle, a 99 percent drop from a 1992 high of more than 37,000 cases. The reductions are a result of banning the use of processed cow products in cattle feed. It turns out that cow cannibalism caused what is considered the classical form of mad cow.
But the infected cow that died in California had an atypical case, the causes of which are still unknown. On the PBS NewsHour last week, Linda Detwiler, a clinical professor at the College of Veterinary Medicine at Mississippi State University, suggests that the “origin may be sporadic [meaning it just occurs], genetic, or it may be a modification of classical BSE.”
Regardless of the type of mad cow, the consumption of its meat by humans is dangerous. The system worked in this case, but are there still risks? Are American eaters, who consume the most meat per capita in world, safe from mad cow?