BSE: Is It Really "Spread"?

Since the December 23 news of the discovery of a BSE case in Washington state, we have all heard or read news stories that mention controlling "... the spread of BSE..."

But is bovine spongiform encephalopathy "spread"? The answer is no, at least not in the way the term is typically used. No evidence of spread from cow to cow in a herd or genetic predisposition has been found with this disease. About half of the herds in the BSE outbreak in the UK experienced only one case, and the majority of the herds had fewer than three cases.

Vertical transmission from cow to calf is possible. Studies suggest that offspring have a less than 10 percent chance of becoming infected from their dam. The likelihood of transmission appears positively related to the disease becoming apparent in the dam within 6 months of the calving date.

Cattle acquire this disease from consuming feed contaminated with the causative agent. The disease is not spread. When feed contamination is eliminated, this condition will die out. Of course, with an incubation period averaging 5 years in the bovine, patience is required.

For more information on BSE, follow links on the Center for Zoonoses Research Web site: http://www.cvm.uiuc.edu/czr/bse.html

Dr. Gavin Meerdink
Beef and Feed Safety Extension Veterinarian
University of Illinois College of Veterinary Medicine