Summer barbecue season is in full swing and it's a good time to review food safety. Food-borne illness is something that almost all of us have experienced at some point in our lives.

Food-borne illness is defined as more than two people having a similar illness with evidence of food as the source. The overall rate of these illnesses has gone down drastically in the last century with improvements in food handling and sanitation. However, we still hear about illness outbreaks.

There are approximately 76 million cases of food-related illness in the United States each year. There are also about 325,000 hospitalizations and 5,000 deaths. Underdeveloped countries, as a group, experience about one billion cases annually and four to six million deaths.

The Centers for Disease Control estimates that 97 percent of all cases of food-borne illness come from improper food handling. Most of these (79 percent) are from commercial establishments, while the other 21 percent originate in the home.

There are a few common denominators that account for most cases of food poisoning. Leaving foods at temperatures that allow bacterial growth is a frequent cause, especially in the summer months when food is left out in warm weather. This can result Staphylococcal food poisoning that is usually seen in foods like potato salad and pies that are high in salt or sugar content.

Raw or undercooked meat is another common source of poisoning; hence the warning to check to make sure cooked meat is not pink in the middle. Cross-contamination of food can lead to problems. This occurs when raw food that may contain organisms or toxins comes into contact with cooked food. Food preparers who don't wash their hands are a major source of problems as well.

Most food-borne illnesses result in diarrhea, vomiting and abdominal cramping. The organisms that cause problems do so by various means, too numerous to mention here. Diarrhea caused by infectious organisms or toxins can be classified as inflammatory and non-inflammatory, depending on how the offending agent affects the victim's intestines.

Inflammatory diarrhea involves actual destruction of the cells that line the intestine. Organisms that cause this inflammation can invade the wall of the intestine and enter the body, causing an immune reaction. Salmonella is a well-known pathogen that causes this type of diarrhea.

Inflammatory diarrhea usually results in smaller stools that can be bloody (also known as dysentery). The victims usually run a fever, have abdominal pain, possibly a headache, and look ill. Severe inflammatory disease may lead to liver and kidney problems as well.

Toxins produced by infectious organisms cause non-inflammatory diarrhea. The toxins act on the cells in the gut causing the release of water and salt into the intestines. This, in turn, results in large volumes of diarrhea without blood or severe abdominal pain.

Ninety percent of cases of food-borne illness resolve in two to three days without antibiotics. The elderly and infants are the most likely groups to develop complications, mainly from dehydration.

People who are ill for more than two or three days, have high fevers, severe abdominal pain or become lethargic should always seek medical attention.

The main objective of treatment for food-borne illnesses is to avoid dehydration. This can usually be accomplished by consuming fluids by mouth. Even if a person is vomiting, they can usually keep down small amounts of fluid given at regular intervals.

There are numerous recommendations for what to use to prevent dehydration or to rehydrate once someone has already become dehydrated. A simple and inexpensive recipe to make at home is to add two level teaspoons of salt and eight heaping teaspoons of sugar to a two liter bottle of water.

Since the ability to absorb sugars from food can be temporarily damaged, it's usually recommended that during the illness and for a few days afterward that patients avoid milk, dairy, and foods containing lactose.

Remember that proper food preparation and handling can go a long way to preventing these illnesses.

Dr. John Roberts is a local physician. His column appears in Monday's edition of the Times, and he has a daily health tip on the front page. Dr. Roberts is one of the owners of Sagamore News Media, parent company of The Times.