Alberta, Canada, has reported its first case of bovine spongiform encephalopathy (BSE), also known as 'mad cow disease', after six years. The case is of the atypical form of the disease, which poses no risk to human health and is not transmissible. The Canadian Food Safety Agency and local health authorities in Alberta are taking necessary steps to prevent the spread of the disease. Atypical BSE is rare and occurs spontaneously in adult cattle. The disease is characterized by damage to the central nervous system and has a 100% mortality rate.