Dec. 14, 2006 -- Lettuce is the leading suspect in the investigation of E. coli cases linked to Taco Bell restaurants in Northeastern states.
The investigation is still under way. Health experts haven't proven that lettuce was to blame.
"I want to reassure our customers that our food is perfectly safe to eat," says Taco Bell President Greg Creed in a Taco Bell news release.
E. coli are bacteria. There are many strains of E. coli; the strain linked to the Taco Bell cases is 0157:H7.
E. coli 0157:H7 can cause diarrhea, which is often bloody. Most healthy adults recover within a week. However, some people can develop hemolytic uremic syndrome (HUS), which can lead to kidney failure.
E. coli Cases
As of Dec. 13, the CDC had reports of 71 people with illness linked to Taco Bell restaurants in four states -- Delaware, New Jersey, New York, and Pennsylvania.
Those patients include 53 people who were hospitalized and eight who developed HUS.
The outbreak peaked in late November, with illness onset dates ranging from Nov. 20 through Dec. 6, according to the CDC.
CDC investigators have interviewed people who ate at Taco Bell and didn't get sick and those who became infected by E. coli.
The CDC's analysis of those interviews suggests that three items -- shredded lettuce, cheese, or ground beef -- were consumed more often by people who fell sick.
Taco Bell's cheese is pasteurized and its beef is cooked. Those processes should kill E. coli bacteria, leaving lettuce as the prime suspect.
The FDA is following the lettuce lead, looking for the farm or farms where the lettuce was grown and any facilities where the lettuce was processed. The FDA is also tracing Taco Bell's cheese sources.
If lettuce was the E. coli source, contamination probably happened before reaching the restaurants, says the CDC.
Green onions had earlier been considered a possible E. coli source. But onions of any type are not linked to this outbreak, according to the CDC.
Lettuce Sold in Most Products
Taco Bell hired an independent lab to test more than 300 samples of all Taco Bell ingredients.
According to Taco Bell, those tests showed that no ingredient, including lettuce and cheese, tested positive for the E. coli 0157:H7 bacteria.
"Lettuce is sold in approximately 70% of our products," Creed says.
"We would expect the vast majority of those who ate at Taco Bell to have consumed lettuce, so we can understand how the CDC has concluded their statistical probability analysis," he continues.
Taco Bell switched one of its lettuce suppliers for its Northeastern region on Dec. 9 as a precaution after the E. coli cases were first reported.
"All lettuce sold in these restaurants today is from a different source, and anything sold prior to December 3, the last date of illness related to Taco Bell, has long been sold or discarded," states Taco Bell.