A report released Thursday by the Centers for Disease Control and Prevention (CDC) shows a leveling of cases for some foodborne infections after a period of decline. For others, incidences of infection which had declined appear to be returning to earlier levels.

The findings are from 2006 data reported to the CDC as part of the agency's Foodborne Diseases Active Surveillance Network (also known as FoodNet). FoodNet monitors foodborne disease and related epidemiologic studies to help health officials better understand the epidemiology of foodborne diseases in the United States.

Camplylobacter, Listeria, Shigella and Yersinia show a sustained decline in incidence compared to baseline data from 1996-1998, but most of the decrease occurred between 1999 and 2002.

The FoodNet data showed there continues to be little change in the incidence of Salmonella cases, and progress made in 2003 and 2004 in reducing the number of cases of with E. coli O157 infections has been lost. Vibrio infections, which are often related to the consumption of raw shellfish like oysters, have increased to the highest level since FoodNet began conducting surveillance.

"As recent outbreaks have shown, too many people in the United States are getting sick each year from foodborne illnesses," said Dr. Julie Gerberding, CDC director. "For instance, the outbreaks involving tomatoes, lettuce and spinach underscore the need to more effectively prevent contamination of produce. We're also working to strengthen our ability to quickly detect and identify foodborne illnesses. We know the faster we can detect an outbreak, the faster we can take actions that will help protect people."

The 2006 FoodNet data indicated that the incidence of infections caused by E. coli O157 and Salmonella was similar to 1996-1998 baseline years. The reasons for the lack of decrease in the incidence of infections caused by E. coli O157 and Salmonella are not fully understood. One possible explanation is the development of cases of disease in foods that previously were not associated with these diseases, such as spinach and peanut butter. Previous efforts to decrease the incidence of E. coli O157 in ground beef and Salmonella in eggs have been successful, but contamination of other foods may be the problem now, according to Dr. Robert Tauxe, deputy director of CDC?s Division of Foodborne, Bacterial and Mycotic Diseases.

"FoodNet is an important part of our food safety efforts," said Tauxe. "We're constantly working to improve our ability to quickly detect foodborne illness outbreaks and determine the cause. With additional resources, particularly at the state and local levels, we can investigate and prevent foodborne illness in a timelier manner."

Consumers can reduce their risk for foodborne illness by following safe food-handling recommendations and by avoiding the consumption of unpasteurized milk, raw or undercooked oysters, raw or undercooked eggs, raw or undercooked ground beef, and undercooked poultry. The risk for foodborne illness can also be decreased by choosing in-shell pasteurized eggs, irradiated ground meat, and high pressure-treated oysters.

The full report, "Preliminary FoodNet Data on the Incidence of Infection with Pathogens Transmitted Commonly Through Food - 10 States, United States, 2006" appears in this week's Morbidity and Mortality Weekly Report (April 13, 2007) and is available online at www.cdc.gov/mmwr. To learn more about FoodNet, please visit http://www.cdc.gov/foodnet/. To learn more about foodborne infections, visit http://www.cdc.gov/ncidod/dbmd/diseaseinfo/foodborneinfections_g.htm.

FoodNet Background

In 1996, the FoodNet surveillance system began collecting valuable information to quantify, monitor, and track the incidence of laboratory confirmed cases of foodborne illnesses caused by Campylobacter, Cryptosporidium, Cyclospora, E. coli O157, Listeria, Shigella, Yersinia and Vibrio. FoodNet is a collaborative effort among CDC, the United States Department of Agriculture, Food and Drug Administration and state surveillance sites. Since its inception, FoodNet has grown to include ten states and 45 million people, about 15 percent of the American population. The ten states are: California, Colorado, Connecticut, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon and Tennessee.