Foodborne Diseases

Foodborne Diseases

Enterohemorrhagic Escherichia coli Infection

Escherichia coli, commonly called E. coli, is just one of many bacteria
that can cause diarrhea. While harmless strains of E. coli normally
occur widely in nature, including the intestinal tracts of humans and
other vertebrates, pathogenic types are a frequent cause of both enteric
and urogenital tract infections. Several different types of pathogenic
E. coli are capable of causing diarrheal disease. A particularly
dangerous type is referred to as enterohemorrhagic E. coli, or EHEC. The
first such strain was identified in the United States in 1982. Since
then, EHEC strains have been associated with foodborne outbreaks traced
to undercooked hamburgers, unpasteurized apple juice or cider, salad,
salami, and unpasteurized milk. The strain of EHEC most commonly found
in the United States is designated O157:H7; but others, including
O26:H11 and O111:H8, also have been found. EHEC strains produce toxins
that have effects similar to those produced by bacteria of the Shigella
genus. These enterotoxins can damage the lining of the intestine, cause
anemia, stomach cramps and bloody diarrhea, and hemolytic uremic
syndrome (HUS) leading to kidney failure. In North America, HUS is the
most common cause of acute kidney failure in children.

Cattle are known to be a reservoir of EHEC, but other domestic and wild
animals and birds can also harbor these bacteria. EHEC and its toxins
are destroyed by heating; therefore, the best assurance against
infection is eating only thoroughly cooked beef and beef products,
avoiding unpasteurized juices, and thoroughly washing uncooked fresh
foods. Good personal hygiene, including hand washing, and disinfecting
work surfaces in the kitchen also are essential to prevent infection or
the spread of this and other enteric diseases.

References and Sources: Medline, Pubmed, National Institutes of Health.

last update: November 2008