The E. coli bacterium has hundreds of strains or types. Most are harmless, and a couple of pathogenic E. coli strains cause only uncomfortable yet benign symptoms such as diarrhea. However, E. coli O157:H7 causes far more destructive results.
E. coli O157:H7 inhabits the intestines of healthy cattle, and is therefore present in their feces. Humans get infected when they consume undercooked ground beef that has been contaminated during slaughter, contaminated drinking water and improperly washed contaminated fruits and vegetables.
Sometimes, the diarrhea is mild and the illness resolves, but often it turns bloody and is accompanied by abdominal cramps and low grade fever. About two to seven percent of people who get infected develop life-threatening complications. The most common of these complications is hemolytic uremic syndrome, a condition marked by destruction of red blood cells and kidney failure. HUS often affects the nervous system and causes seizures and coma. It is estimated that at present, 73,000 cases of the infection that result in 61 deaths occur annually in the United States.
Antibiotics are not routinely used in the treatment of E. coli O157:H7 infection, because, according to some experts, they may even precipitate kidney failure.
E. coli O157:H7 infection can be prevented by:
• Cooking ground beef thoroughly
• Washing fruits and vegetables adequately
• Not drinking milk, milk products and juices that have not been pasteurized
• Making sure drinking water is safe
• Observing good personal hygiene and sanitary practices (e.g., wash hands with soap and water after using the toilet and before preparing food)