E. coli O157:H7 was identified for the first time at the CDC in 1975, but it was not until seven years later, in 1982, that E. coli O157:H7 was conclusively determined to be a cause of enteric disease. Following outbreaks of foodborne illness that involved several cases of bloody diarrhea, E. coli O157:H7 was firmly associated with hemorrhagic colitis.

The Centers for Disease Control and Prevention (CDC) estimated in 1999 that 73,000 cases of E. coli O157:H7 occur each year in the United States. Approximately 2,000 people are hospitalized, and 60 people die as a direct result of E. coli O157:H7 infections and complications. The majority of infections are thought to be foodborne-related, although E. coli O157:H7 accounts for less than 1% of all foodborne illness.

E. coli O157:H7 bacteria are believed to mostly live in the intestines of cattle but have also been found in the intestines of chickens, deer, sheep, goats, and pigs. E. coli O157:H7 does not make the animals that carry it ill; the animals are merely the reservoir for the bacteria.

While the majority of foodborne illness outbreaks associated with E. coli O157:H7 have involved ground beef, such outbreaks have also involved unpasteurized apple and orange juice, unpasteurized milk, alfalfa sprouts, and water. An outbreak can also be caused by person-to-person transmission of the bacteria in homes and in settings like daycare centers, hospitals, and nursing homes. We are involved in representing families of children who have suffered from this bacterium.