Shiga toxin-producing Escherichia coli (STEC) are a group of gram-negative bacteria that can produce potent toxins. STECs are emerging as an important cause of food borne illness worldwide. The most recognized serotype is E. coli 0157:H7, but there are more than 100 different strains that can also cause disease. Illnesses caused by STEC range from mild, watery diarrhea lasting a couple of days to serious and life-threatening conditions such as hemorrhagic colitis, hemolytic uremic syndrome or thrombocytopenia purpura and death. Anyone can become infected with STEC, but young children and the elderly are most susceptible. Symptoms of infection are not always clear and can resemble other illnesses. Symptoms may include abdominal cramping, sudden onset of watery and/or bloody diarrhea and vomiting. Usually, little or no fever is present. Infection is transmitted primarily by contaminated food. Most illness has been associated with eating undercooked contaminated ground beef. Other food products implicated in outbreaks are: salami, pork, poultry, lamb, raw milk, alfalfa sprouts and unpasteurized apple cider and apple juice. Bacteria in diarrheal stools of infected persons can also be passed from person to person if hand hygiene practices or cleanliness is inadequate. Water transmission via contaminated swimming water has also been reported. Recent outbreaks of E. coli 0157:H7 in young children have occurred among agricultural fair, festival and petting zoo visitors. As a result, the Centers for Disease Control and Prevention (CDC) issued new guidelines to strengthen disease prevention and control measures. These measures include restricting entry of young children into open-interaction areas of agricultural fairs, festivals and petting zoos and reducing direct contact with the animals. In addition, the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) have approved irradiation of meat in an attempt to reduce bacterial contamination in consumer meat supplies. Most people recover from STEC infection without antibiotics within five to ten days. Supportive therapy, including fluids and watching for signs of complications or worsening symptoms, is recommended. Treatment with antibiotics remains controversial. Anti-diarrheal medications appear to prolong the bloody diarrhea and should be avoided. No specific medication is available yet for treatment of STEC infection.
Wash your hands after using the bathroom, before preparing or eating food, after changing diapers, after contact with animals and after contact with someone who is ill. Cook all meats and poultry thoroughly. Avoid unpasteurized food and drinks. Wash fruits and vegetables thoroughly, especially those that will not be cooked. Avoid swallowing lake or pool water while swimming. Anyone with a diarrheal illness should avoid swimming in pools or lakes and preparing food for others. Additional information on E.coli 0157:H7 or Shiga toxin-producing E. coli can be found on the Centers for Disease and Prevention Web site.