Animal issues associated with Escherichia coli O157:H7.

Zoonosis Update Since Escherichia coli O157:H7 was first recognized in 1982 as a human pathogen, considerable progress has been made in elucidating principal vehicles of transmission. Cattle have been identified as a major source of E coli O157:H7 infection of humans, with as many as 1 in 4 animals at slaughter shedding the pathogen in feces during the summer months. 1 Case-control studies of sporadic cases of E coli O157:H7 infection in the United States, Canada, and Europe have identified eating undercooked ground beef, visiting farms, and handling animals on the farm as principal risk factors for infection. 2,a Cattle manure, of which an estimated 1.2 billion tons are produced annually in the United States, 3 appears to be a principal source of the E coli O157:H7 problem. Animals, water, and food that contact cattle manure are potential vehicles of E coli O157:H7. An effective control program to substantially reduce E coli O157:H7 infections will require the implementation of intervention strategies throughout the food continuum, from farm to table. Promising intervention measures at the farm include competitive exclusion bacteria, bacteriophage, and targeted animal management practices addressing common points of contamination. Innovative intervention treatments are under development for use by food processors; however , most treatments have limitations that restrict their use to specific types of foods. For example, irradiation can create major off odors and flavors in foods that contain more than 10% fat. Consumers also have a role in implementing intervention controls in food handling and preparation. Unfortunately, many consumers eat high-risk foods, improperly handle and store foods, and ignore warnings regarding foods known to be unsafe. We all have a role in reducing the risk of foodborne illness , including E coli O157:H7 infections, but clearly more needs to be done on the farm, including validating proposed and developing innovative on-farm control measures. Public Health Concerns Estimates by the Centers for Disease Control and Prevention (CDC) indicate that enterohemorrhagic E coli (EHEC) serotype O157:H7 is responsible for approximately 62,500 cases of foodborne infection annually in the United States. 4 These estimates include hospitalizations and 52 deaths, which are largely associated with cases of pediatric hemolytic uremic syndrome (HUS), a leading cause of renal failure in children. Sporadic cases in adults are less likely to be diagnosed and reported, because the gastrointestinal disease can be mild. The CDC, using the FoodNet surveillance system, reported an overall incidence of 2.1 …