But it can also be caused by bacteria, either foodborne or personally transmitted, he said.

CNN: Queen Elizabeth II hospitalized for stomach bug

Please join us in our fight against foodborne illness and have a safe and happy summer.

WHITEHOUSE: Food Safety Week Kick Off

Although pesticides are not a cause of foodborne illness, produce can be a source of food poisoning.

CNN: Food poisoning: What you need to know

But some strains of E. coli are responsible for serious foodborne infections, including those that can lead to hemolytic uremic syndrome.

CNN: Hemolytic uremic syndrome (HUS)

However, unlike some other foodborne parasites, cyclospora doesn't become infectious until days or weeks after it's passed in a bowel movement.

CNN: Cyclospora infection

The U.S. Department of Agriculture (USDA) has an online reporting tool for those who think they might have a foodborne illness.

CNN: Food poisoning: What you need to know

The other rule sets out guidelines for "preventive controls for human food" and would require companies to have plans for foodborne illnesses.

CNN: New FDA rules target foodborne illnesses

Health officials point out that this flu is not a foodborne illness.

CNN: CDC: Cases of new swine flu strain rising

Each year one out of every six Americans gets sick from foodborne illnesses, according to estimates by the Centers for Disease Control and Prevention.

CNN: New FDA rules target foodborne illnesses

"Use of an instant-read thermometer to determine doneness of meat and poultry is one of the best lines of defense against foodborne bacteria, " said J.

CNN: graphic

Tracking down the source of a foodborne infection is notoriously difficult.

ECONOMIST: Tech.view

For example, only 20 years ago Listeria, E. coli O157:H7, Campylobacter and Cyclospora, all of which have caused recent outbreaks, were not known to cause foodborne illness.

ECONOMIST: Food poisoning

As of press time, it appears that a foodborne bacterium thriving on the leaves of bagged spinach from Natural Selection Foods had sickened 173 people, hospitalized 92 and killed 1.

FORBES: Don't Eat Your Spinach

Fortunately, the testing did not reveal strains of E. coli 0157, a particularly virulent form of the bacteria that was responsible for several outbreaks, and deaths, from serious foodborne illnesses.

CNN: Yuck! What's in your pool water

Washington (CNN) -- The Food and Drug Administration proposed two new rules Friday that it estimates could eliminate up to 1.25 million foodborne illnesses each year from such pathogens as Salmonella, Listeria and E.

CNN: New FDA rules target foodborne illnesses

As Salmonella rates continue to stagnate, we look forward to CSPI's support, and the support of other groups committed to food safety, of our efforts to reduce this dangerous foodborne pathogen, including modernization of the poultry inspection system.

CNN: Food poisoning: What you need to know

Improving food safety begins before the products ever reach the consumer, at the slaughterhouse and in the fields, but "being careful in the kitchen is also very important, " said Dr. Robert Tauxe, deputy director of the CDC's Division of Foodborne, Waterborne and Environmental Diseases.

CNN: Food poisoning: What you need to know