The Food Poisoning Epidemic

ATLANTA -- Next time you have a case of diarrhea that lasts a day or more, chances are better than 1 in 3 that it was food poisoning. As many as a quarter of Americans suffer a foodborne illness each year -- though only a fraction of those cases get linked to high-profile outbreaks like the recent salmonella-peanut scare, according to the U.S. Centers for Disease Control and Prevention.

"Outbreaks are dramatic instances," says Dr. Robert Tauxe, a CDC expert on the subject. But they highlight a health threat that many people exaggerate and misunderstand, according to some experts.

Scientists have counted more than 250 food-related types of illness -- from viruses to bacteria to parasites. Most common are Norwalk-like viruses -- famous for sickening cruise-ship passengers. They account for about two-thirds of known food-poisoning cases, according to the CDC.

Two types of bacteria, campylobacter and salmonella, are the next most common. Campylobacter is blamed for about 14 percent of food poisonings, salmonella for roughly 10 percent.

The exact toll of these and other bugs is not really known.

Ten years ago, a team of CDC scientists put together the best enduring estimate of how many Americans get food poisoning each year: 76 million illnesses, which resulted in 325,000 hospitalizations and 5,000 deaths.

No more recent figures are available. But the current numbers must be close to 87 million cases, 371,000 hospitalizations and 5,700 deaths, according to an Associated Press calculation that used the CDC formula and current population estimates.