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Definition of Food poisoning

< b>Food poisoning: A common flu-like illness typically characterized by nausea, vomiting and diarrhea, due to something the victim ate or drank that contained noxious bacteria, viruses, parasites, metals or toxins.

The most prominent causes of food poisoning are Norwalk virus and Norwalk-like viruses, Campylobacter jejuni, Salmonella, Listeria monocytogenes, Vibrio vulnificus, and E. coli O157:H7. Following is a short summary of the food poisoning due to each of these causes:

• Norwalk virus and Norwalk-like viruses -- These fairly benign viruses account for two-thirds of food poisoning attacks. They are highly infectious and spread through contamination of food by small amounts of human feces. Within a day or two of consuming the tainted food -- typically shellfish (raw or improperly steamed clams and oysters from polluted waters) and salad ingredients -- victims develop abdominal pain, watery diarrhea, nausea and vomiting, possibly with a headache and low-grade fever. Some people also suffer severe cramping or bloody diarrhea, but most get better in 24 to 60 hours.

• Campylobacter jejuni -- Now the leading cause of bacterial food poisoning, most often spread by contact with raw or undercooked poultry. The number of organisms in a single drop of juice from a contaminated chicken is enough to make someone sick.

  Symptoms tend to start 2-5 days after exposure and typically last a week. Symptoms resemble viral gastroenteritis -- diarrhea, fever, abdominal pain, cramping, nausea and vomiting -- but with Campylobacter, fever is typical and the diarrhea is often bloody.

  Most victims get better without specific treatment, but those with immune deficiencies may benefit from two weeks of antibiotics. And everyone with diarrhea should maintain a high intake of fluids for as long as it persists.

• Salmonella -- Almost any food can carry the bacteria that cause salmonellosis -- raw and undercooked eggs most often, but also poultry, raw meat, dairy products, pasta, shrimp, sauces, salad dressing, fresh vegetables, chocolate, coconut, peanut butter and even yeast. Salmonella may be present INSIDE AN EGG, merely on its shell. Abdominal cramping and diarrhea typically occur 6 to 48 hours after exposure and may be accompanied by fever, headache, nausea and vomiting.

  Though salmonella bacteria account for only about 10% of food poisonings, they are responsible for nearly a third of food-related deaths. Antibiotics are not recommended except for people with immune deficiencies, infants, the elderly and people with severe illnesses.

• Listeria monocytogenes -- This organism can cause encephalitis, meningitis, blood-borne infection and death. It is especially hazardous for pregnant women (posing a threat of miscarriage or stillbirth), newborn babies, the elderly and immune-deficient patients. It causes about 28%of deaths due to food poisoning.

  Listeria can survive acid, nitrite and salt and can thrive even in the refrigerator, is most commonly found in raw (unpasteurized) milk, soft-ripened cheeses like Brie and ready-to-eat meats like hot dogs and pâté. Other sources of listeria include raw and smoked fish, raw meats and poultry, cooked poultry, fresh vegetables and ice cream.

  Listeriosis (listeria infection) starts insidiously, with headache, low-grade fever, muscle aches, nausea and vomiting and is often mistaken for a viral illness that will cure itself. Those factors cause treatment delays and allow the disease to progress. Symptoms can appear anywhere from 3 to 70 days after exposure.

  Listeria infections must be treated with injectable antibiotics -- penicillin, ampicillin or gentamicin -- or intravenous trimethoprim/sulfamethoxazole. Prevention is the best defense. Those at greatest risk should avoid foods that are most likely to harbor listeria or they should cook those foods until piping hot (180 degrees) before tasting them.

• Vibrio vulnificus -- This organism can be ingested through raw or inadequately cooked seafood from warm seawaters, especially raw oysters and clams. Within 16 hours to 2 days, victims develop an abrupt case of gastroenteritis, with abdominal pain, diarrhea and vomiting. People with chronic illnesses, especially liver disease, can develop a fatal blood-borne infection. Antibiotics -- doxycycline, tetracycline, gentamicin or ceftazidime -- can be lifesaving when given at the first sign of a severe infection.

• E. coli O157:H7 -- Contamination can occur in almost any food that has not been heated to a bactericidal temperature. It has caused serious and even fatal illness after the consumption of hamburgers, unpasteurized apple juice and lettuce, among other foods. Fresh-squeezed juice, consumed soon after preparation, is not a problem.

  The bacteria produce a toxin that causes severe abdominal cramps and watery diarrhea that becomes bloody. Consumption of a very small dose can result in life-threatening illness in otherwise healthy people. Young children, a number of whom have died, and the elderly are especially vulnerable to a complication called hemolytic uremic syndrome, marked by severe anemia and kidney failure, that may start 2 to 14 days after the first symptoms. Antibiotics, which may do more harm than good. There is no specific treatment to prevent hemolytic uremic syndrome.

Common Misspellings: food poisioning