Mad cow disease: documented cases in North America.
D000818:Animals; D002170:Canada / Q000453:epidemiology; D002417:Cattle; D003257:Consumer Product Safety; D016643:Encephalopathy, Bovine Spongiform / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission*; D006801:Humans; D012307:Risk Factors; D012308:Risk Management; D014481:United States / Q000453:epidemiology