E. coli O157:H7 Outbreaks: When Science Speaks but No One Listens

By: Suzanne Osborne, Ph.D

On September 3rd, 2012, a routine inspection of Canadian beef crossing the American border snowballed into one of the largest food recalls in Canadian history. Within 12 days, more than 1.5 million pounds of beef originating from XL Foods Inc., located in Brooks, Alberta had been recalled due to contamination with Escherichia coli. As one of Canada’s largest beef processing plants, XL Foods’ distribution list included over twenty countries. To date, sixteen people have reported illness due to the contamination with E. coli O157:H7 (1). Resulting infections typically cause severe cramping and bloody diarrhea caused by the destruction of cells lining the intestine (3,4) and, in some cases, can lead to haemolytic uraemic syndrome, potentially causing rapid kidney failure (4). Cattle are the major source of E. coli O157:H7. These bacteria can attach to the wall of a cow’s intestine without causing disease in the animal, enabling them to shed the bacteria into the environment, contaminating other cattle, groundwater and vegetation (2,3,4). The ability to identify infected cattle is extremely limited.