April 15, 2010 -- Illnesses caused by a potentially deadly strain of E. coli have been cut in half since the mid-1990s, meeting a target set following a particularly serious outbreak of the food-borne pathogen, CDC officials say.
In 1993, hundreds of people became ill and four children died following an outbreak of Echerichia coli O157 traced to undercooked fast-food hamburgers.
Soon after the outbreak, federal officials set the goal of reducing E. coli O157 illness to no more than one case per 100,000 people by 2010.
That goal was reached in 2009, CDC officials now say. But they add that there has been little progress in reducing illness from other food-borne pathogens in recent years.
E. coli Illness Lowest Since 2004
Along with the FDA, the U.S. Department of Agriculture, and 10 state health departments, the CDC has been tracking illnesses caused by nine food-borne pathogens since 1996 through the FoodNet program.
During the first years of surveillance, significant declines were seen in illness caused by most of the pathogens. But with the exception of E. coli, food-related illness has not declined much since 2004, officials now say.
Chris Braden, MD, of the CDC said at a news conference that illnesses caused by E. coli have dropped by 25% over the past three years and are at their lowest levels since 2004.
Braden is the CDC's acting director of the Division of Foodborne, Waterborne and Environmental Diseases.
"This decrease may be due, at least in part, to continuing efforts to decrease contamination of ground beef and leafy green vegetables consumed raw," he says.
E. coli outbreaks in the fall and early winter of 2006 were traced to fresh bagged spinach and lettuce.
Since last summer, meat processors have been required to test all components of meat used in ground beef. Around the same time, inspectors received new guidelines for evaluating sanitation in meat processing plants.
David Goldman, MD, MPH, administrator of the U.S. Department of Agriculture Food Safety and Inspection Service (FSIS), attributed much of the E. coli decline to these changes.
Salmonella 'Still a Challenge'
Raw and undercooked poultry and eggs are major sources of salmonella illness.
FSIS inspectors reported a decline in processed poultry contaminated with salmonella in 2009, compared to 2006, and an increase in processing plants that met the agency's standards for preventing contamination, according to the report.
But Braden says these improvements have not translated into hoped for declines in salmonella illness.
"Salmonella continues to be a challenge," he says. "Salmonella is the most commonly diagnosed and reported food-borne illness. The incidence of salmonella infections has declined by 10% since surveillance began in 1996, but it is furthest of any of the pathogens from the goals we have set for reductions."
Oyster-Related Illness Increasing
Other highlights of the annual FoodNet report include:
- Food safety officials could not explain why illnesses related to vibrio bacteria have increased by 85% since reporting begin. Raw and uncooked oysters are the most common cause of vibrio illness.
- Other than E. coli, the only significant decline in recent years has been in shigella infections. Some shigella is transmitted by food, but most infections come from person-to-person contact. Child day-care centers are common sources of infection.
- For most infections, the illness rate was highest among children under the age of 4, but people over 50 had the highest rates of hospitalization and death.
Goldman says food preparers can have a big impact on food-borne illness by following the U.S. Department of Agriculture's food safety advice to cook, separate, clean, and chill.
- Cook all foods to a safe internal temperature to destroy bacteria.
- Separate cooked and uncooked foods, as well as those eaten raw and those cooked before eating.
- Clean your hands and work surfaces frequently while cooking.
- Chill foods that need refrigeration and never let these foods sit at room temperature for more than one or two hours.