The U.S. remains free of foot-and-mouth disease (FMD) and Bovine Spongiform Encephalopathy (BSE), or what's commonly referred to as mad cow disease. There have been no cases of either disease in the U.S., due in large part to aggressive prevention measures designed to protect U.S. cattle herds and assure the safety of the beef supply for American consumers. Below is a summary of facts about FMD and BSE, including prevention measures for both: