Lettuce now suspected in E. coli cases at Taco BellDec 14, 2006 | AP Lettuce was the most likely source of an outbreak of E. coli linked to Taco Bell, federal health officials said Wednesday.
Officials said the outbreak appears to be over and that tracing the source of the suspected lettuce could prove difficult because the shredded lettuce was processed in bulk.
Taco Bell had said contaminated green onions were responsible for the cases of food poisoning 71 confirmed cases of E. coli in five states, primarily New Jersey, New York and Pennsylvania, as of Wednesday, according to the Centers for Disease Control and Prevention.
Follow-up government testing, however, failed to confirm that.
Interviews led investigators to think that lettuce was the probable culprit, health officials said.
"That I would say is the most likely vehicle. I would warn we are not done with the investigation," Dr. Christopher Braden, a medical epidemiologist with the CDC, told reporters.
Investigators had considered cheddar cheese and ground beef as well. They said Taco Bell's menu, which offers various combinations of the same ingredients, made it difficult to pinpoint the source of the contamination.
The Food and Drug Administration plans to try to trace the lettuce to its source, said Dr. David Acheson, chief medical officer of the agency's Center for Food Safety and Applied Nutrition.