Restaurant Workers

Diseases

The most commonly recognized food borne infections are caused by bacteria and a group of viruses called calicivirus or Norwalk. Some food borne infections are also caused by toxins produced by microbes that can cause illness even if the microbes are no longer in the food. The bacterium Staphylococcus aureus, for example, produces a toxin that causes intense vomiting, and the rare, fatal disease botulism occurs when the bacterium Clostridium botulinum produces a powerful paralytic toxin. Luckily, botulism is completely inactivated by boiling. Pesticides and poisonous mushrooms and fish can also lead to illness.

Bacteria and viruses common to food bourne illness include:

Campylobacter - a bacterium that causes fever, diarrhea and abdominal cramps. These bacteria live in the intestines of healthy birds, and most raw poultry meat has Campylobacter on it. Humans can contract this bacterium by eating undercooked chicken, or other food that has been contaminated with raw chicken juices.

Salmonella - a bacterium that is widespread in the intestines of birds, reptiles and mammals. The bacterium causes the illness salmonellosis, which includes fever, diarrhea and abdominal cramps. In people with weakened immune systems, the bacteria can invade the bloodstream and cause fatal infections.

E. coli O157:H7 - a bacterium that lives in cattle and similar animals. Human illness typically follows consumption of food or water that has been contaminated with cow feces. E. coli causes severe bloody diarrhea and painful abdominal cramps. In about 5% of cases, a complication called hemolytic uremic syndrome (HUS) occurs several weeks after the initial symptoms and can cause temporary anemia, profuse bleeding and kidney failure.

Calicivirus or Norwalk virus - an extremely common cause of food borne illness that causes gastrointestinal illness, usually with more vomiting than diarrhea. Norwalk viruses spread primarily from one infected person to another. Infected kitchen workers can contaminate a salad or sandwich as they prepare it, and infected fishermen have contaminated oysters as they harvested them.

Some diseases that are not commonly considered food borne because they are generally transmitted by other routes are hepatitis A, Shigella and strep infections, as well as the parasitic Giardia lamblia and Cryptosporidia.

Precautions that can reduce the risk of food born disease include:

Cooking meat, poultry and eggs thoroughly - use a thermometer to measure the internal temperature of meat. The minimum internal temperature for meat products is 160o F. Eggs should be cooked until the yolk is firm.

Separate foods so that there is no cross-contamination - wash hands, utensils, and cutting boards after they have been in contact with raw meat or poultry and before they touch other foods.

Refrigerate leftovers promptly - bacteria grow quickly at room temperature, so leftovers should be refrigerated within four hours.

Clean produce and hands - rinse fruits and vegetables in running tap water. Bacteria can grow on the cut surface of fruits or vegetables, so avoid leaving cut produce at room temperature for many hours. Wash your hands with soap and water before preparing food to avoid becoming the source of food born illness.