Care, cleanliness prevent food poisoning


August 23, 1994|By Dr. Genevieve Matanoski | Dr. Genevieve Matanoski,Medical Tribune News Service

It happens every summer, sure as checkered tablecloths, pitchers of lemonade and pickup softball games. The idyllic setting of a country picnic or the spontaneous fun of a backyard cookout is tempered by someone getting food poisoning.

Although rarely fatal, food poisoning can pose serious immediate health problems, and a miserable time for its sufferers. It also isn't relegated to the warm-weather months only. Still, with some simple precautions, the risk of contracting food poisoning -- at a summer picnic or Thanksgiving dinner -- can be dramatically reduced.

For more information on food poisoning and how to prevent it, I consulted George Jakab, a professor in the Department of Environmental Health Sciences at Johns Hopkins School of Public Health.

Q: What is food poisoning?

A: Over time, foods deteriorate due to microbiologic, physical, chemical or enzyme-induced decay. During this decay, poisons known as toxins are produced by bacteria growing in the food, or by bacteria that are ingested and then multiply in the body.

It is these toxins, not the producers of them, that make people ill. Even with modern food processing, which reduces or eliminates many toxins, food poisoning still occurs -- mostly because of human error.

Q: What are some of the leading types of food poisoning and their symptoms?

A: One of the most common types of food poisoning is caused by staphylococci bacteria. This organism will multiply in food that has been improperly cooked, stored or handled. Nausea, cramps, vomiting and/or diarrhea usually appear from one to six hours after ingesting the toxin in staphylococci-contaminated food. Vomiting and diarrhea are signs that the gastrointestinal tract is ridding itself of the toxin. In most cases, people with staph food poisoning feel better in a day. Symptoms that persist should be reported to a doctor.

Botulism, caused by Clostridium botulinum, is a much more serious type of food intoxication. Though only a handful of cases typically occur in the United States each year, botulism frequently is fatal. Most cases are traced to improperly canned home foods, although commercially processed foods sometimes may be the culprit. The incubation period for botulism usually is between eight and 14 hours. A mild upset stomach is rapidly followed by dizziness, headache, blurred or double vision, muscle weakness, difficulty in swallowing and speaking, respiratory failure and coma. Death may result from respiratory paralysis. If botulism is suspected, immediate medical attention is required.

Salmonella food poisoning, another serious illness, can come from undercooked poultry, raw or rare meat or contaminated eggs and dairy products, among other sources. Unlike staphylococcus and botulism, where bacteria grow in food, salmonella bacteria multiply in the intestines and produce toxins. Because of this, symptoms may surface anywhere from six hours to two days after eating contaminated food.

Symptoms of salmonella poisoning include abdominal cramps, diarrhea, chills and fever lasting from three to seven days. Chronic arthritis may follow a bout of this disease.

Seafood poisoning results from a variety of algae-produced toxins that contaminate shellfish such as mussels, clams and oysters; it also can result from ciguatera poisoning, which can be caused by eating any contaminated fish. Both are serious and potentially fatal.

Shellfish poisoning symptoms usually apear within half an hour, and include nausea, vomiting and respiratory paralysis. Emergency treatment is required. Ciguatera poisoning becomes apparent within one to five hours. Nausea and fatigue progress to increased salivation, sweating, dizziness, blurred vision and difficulty in breathing. Without emergency treatment, the victim can suffer respiratory failure.

Q: What steps can I take to prevent food poisoning?

A: One cardinal rule is to keep cold foods cold (below 40 degrees Fahrenheit) and hot foods hot (above 140 degrees Fahrenheit.) Bacteria thrive at temperatures in between, including room temperature. Because of this, thaw frozen foods in the refrigerator, microwave or in a plastic wrap under cold water -- never leave them to defrost on the kitchen counter. Put cooked food into the refrigerator or freezer while still warm.

Avoid contact between raw and cooked foods. Do not eat raw meat and fish. Handle carefully foods high in moisture and protein, such as milk and milk products, eggs, meat, poultry, fish, shellfish and such foods as cream pies, custards, sandwich fillings and salads (especially tuna, chicken and potato).

Also, do not overlook the obvious. Simply washing your hands before handling food plays a major role in preventing foodborne illness. Keep work surfaces and utensils clean, especially after cutting raw poultry and meat. Avoid mixing foods with your hands. Protect foods from insects, rodents and other animals.

Dr. Matanoski is a physician and epidemiologist at the Johns Hopkins School of Hygiene and Public Health. She is founding director of its Institute for Women's Health Research and Policy.

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.