In December, 2006, more than three dozen people became ill after having eaten in eleven Taco Bell restaurants. The infection: Escherichia coli, an organism which has caused serious illness, renal failure and death. The restaurant chain determined that the infection had been caused by green onions, and subsequently removed them from its stores nationwide. But before the outbreak was identified, at least 42 people in New Jersey and 1 in Pennsylvania fell ill with E coli 0157:H7. During the outbreak, 9 people were hospitalized, and one suffered kidney damage.
This outbreak of E coli was not to be the last one associated with Taco Bell restaurants in 2006. Later that year, another outbreak was found to be caused by contaminated lettuce, which was traced to a specific farm in California, where poor water drainage and proximity to a dairy farm were cited as reasons for the contamination.
The outbreaks of 2006 have made it clear that a better understanding of how food becomes contaminated is necessary to stop further outbreaks of foodborne illnesses. The primary source of E coli 0157:H7 contamination and infection is cattle, either in contaminated meat, or produce that has been contaminated with cow manure. Testing, changes in preparation and processing methods, and environmental controls are being instituted in a collaborative effort to prevent contamination of produce and meat. The USDA is supervising this effort.
Healthcare workers also need to be educated in early detection of the signs and symptoms of foodborne infections of E coli 0157:H7. Signs and symptoms of E coli 0157:H7 infection are abdominal cramps, bloody diarrhea, and in severe cases, a complication known as hemolytic uremic syndrome (HUS), which causes acute kidney failure. A small proportion of those who suffer HUS have immediate complications with lifelong implications such as blindness, paralysis, persistent kidney failure, or permanent bowel dysfunction due to the necessity of having part of the bowel removed.
The infection is diagnosed by stool cultures, but since only 2/3 of laboratories do routine testing for E coli 0157:H7, it is important that clinicians be able to recognize the symptoms early and request that testing be done on all persons who suddenly have bloody diarrhea. There is no specific treatment for E coli 0157:H7, and most people recover within 5 to 10 days. The infection is not usually treatable with antibiotics, and it is thought that some antibiotics might even lead to the kidney complications some have suffered.
Prevention in the healthcare facility involves attention to the methods used in preparation and handling of food. Following are some recommended measures that can be taken to prevent any foodborne illnesses.
l Use a food thermometer for all meats, especially ground beef.
l Ground beef patties should be cooked until the thickest part reads at least 160°F.
l All produce should be washed thoroughly.
l Raw meat should be kept separate from ready-to-eat foods.
l Dishes which have held raw meat should never be used to serve food.
l Meat thermometers should be disinfected before reuse.
l Use only pasteurized milk, juice or cider.
l Foodservice areas should be kept clean and disinfected regularly.
l Staff handling food should observe proper hand hygiene.
l Serve all food promptly. Do not serve food that has been sitting out.
l Refrigerate all food not to be served promptly. Refrigerators should be set at 40°F and freezers at 0°F. Settings should be checked occasionally with a thermometer.
Reference: www.cdc.gov/ncidod/dbmd/diseaseifo/foodborneinfections_g.htm
www.fsis.usda.gov/OPPDE/rdad/FRPubs/95-033F/95-033F_Appendix%20B.htm
www.cdc.gov/ncidod/dbmd/diseaseinfo/escherichiacoli_g.htm