Foodborne and Waterborne Illness: Nutritional Considerations

Foods of animal origin, particularly meat and eggs, are the most common causes of foodborne illness. Investigators working with the Food and Drug Administration (FDA) have discovered that resistant strains of salmonella are common in retail ground meats, including ground chicken, beef, turkey, and pork.

Raw oysters and other shellfish may be a source of vibrio infection if they come from contaminated waters, particularly the Gulf of Mexico. The U.S. Department of Agriculture (USDA) listed eggborne infection with salmonella as an important public health problem in the United States in 2000, and it continues to be a problem due to products that contain undercooked eggs, such as mayonnaise, ice cream, and custards.

In addition, dairy farms are a potential source of listeria infection, which is responsible for 28 percent of U.S. food-related deaths every year. Other studies have found that dairy farms are also a source salmonella, E. coli, and yersinia infections.

Produce may become contaminated with fecal pathogens during planting, irrigating, harvesting, processing, and shipping, or through contaminated water.

Food service establishments can be a frequent source of foodborne infection, although the risk is also present in homes and any other setting that allows for lapses in preparing, cooking, and storing food. A 2005 survey of food service personnel found that more than 50 percent did not always wear gloves while touching ready-to-eat foods; almost 25 percent did not follow appropriate hand-washing guidelines; more than 33 percent did not always change gloves between handling raw meat and ready-to-eat foods; and more than 50 percent did not use a thermometer to check food temperatures. All these precautions should be used in any setting where food is prepared.

The Centers for Disease Control, FDA, and USDA have established the Foodborne Diseases Active Surveillance Network (FoodNet). FoodNet's purpose is to monitor trends in foodborne diseases and assess which diseases are attributable to specific foods and settings in the United States. You can visit FoodNet at www.cdc.gov/foodnet.