Prepackaged iceberg lettuce from California has been linked to two separate outbreaks of E. coli that sickened more than 150 Taco Bell and Taco John's customers late last year on the East Coast and in the Midwest, the U.S. Food and Drug Administration said Friday.
The news comes just months after officials fingered prepackaged California spinach in an outbreak of E. coli O157:H7 that sickened more than 200 people and killed three.
It deals another blow to California's leafy greens industry, which dominates the nation's supply. The iceberg lettuce industry alone harvested $750 million worth of greens in 2005 -- nearly 75% of the nation's crop. Most of it was grown in the Greater Salinas and Central valleys.
"It just adds more fuel to the fire of the need to address this," said Dr. David Acheson, chief medical officer for the FDA's food safety center.
The recent outbreaks apparently have vindicated concerns he voiced last September, when he unenthusiastically announced his agency's decision to lift a warning against eating fresh bagged spinach from California's Central Coast. He pointedly noted at the time that of the 20 E. coli outbreaks from lettuce and spinach since 1995, nine were linked to the Greater Salinas Valley.
"Until some fundamental fixes are put in place in the areas where this contamination is happening," Acheson said during a conference call with reporters, "there is obviously a concern that two months from now we'll be having the same conversation, talking about outbreak No. 21."
And, indeed, outbreaks No. 21 and 22 occurred about two months later. People began falling sick after eating at the fast food chains Taco Bell and Taco John's in November. In the Taco Bell outbreak, which involved restaurants in New Jersey, New York, Pennsylvania and Delaware, seventy-one fell ill and 53 were hospitalized. The Taco John's outbreak involved three eateries in Minnesota and Iowa. Eighty-one were sickened, including 26 who were hospitalized.
Wider area affected
Outbreaks 21 and 22 also showed that problems in California extend beyond the Greater Salinas Valley, where the tainted spinach was grown.
Taco Bell's tainted lettuce was traced, via packaging, to farms in the Central Valley, although no specific sources have been named. The Taco John's produce was traced both to the Central Valley and to the coast south of Salinas.
As with the spinach outbreak, investigators suspect that the initial point of lettuce contamination occurred at the farms, not in processing or distribution, said Jack Guzewich, director of emergency coordination and response for the FDA's food safety center.
Conflicting land uses
One potential problem is the proximity of ranching and farming operations in parts of California. Cattle and other animals harbor the bacteria, which is shed in their feces.
Indeed, officials said, the same sub-strain of E. coli involved in the Taco John's outbreak was found in two unidentified "environmental samples" from dairy farms next to one of the chain's lettuce growers.
In the spinach outbreak, the implicated greens were ultimately traced to four farms in Monterey and San Benito counties. Near one of the farms, which was next to a cattle ranch, officials found the sub-strain that caused illnesses in cow manure, a wild pig's intestines and creek water.
The three successive outbreaks, all of which have run their course, also raise questions about what is causing them to occur with such frequency, said Trevor Suslow, a UC Davis food pathologist.
"The fact that it seems to be happening even more frequently, in a more compressed time frame, one would have to speculate something is either being missed or something has changed to elevate the level of risk or potential of contamination," Suslow said.
Tim Chelling, spokesman for the Western Growers Assn., said one possibility is increased vigilance by public health authorities, enabling outbreaks to be detected faster and with more precision.
"I think it's an indication of the heightened sensitivity of the food safety network," Chelling said. "At the same time, everyone here is treating it as the serious matter that it is."
Brian Dixon, spokesman for Cheyenne, Wyo.-based Taco John's International Inc., said it was a relief that investigators are making progress in their probe.
"Getting that more definitive data will help everyone to determine how we might address these threat situations in the future," Dixon said.
Rob Poetsch, a spokesman for Irvine-based Taco Bell Corp., emphasized that the outbreak was not related to "the sanitary conditions at any of our restaurants."
Both Taco Bell and Taco John's switched produce suppliers after their respective outbreaks. They did not share the same suppliers, Dixon said.
The E. coli strain involved in the outbreaks, O157:H7, is particularly dangerous because it adheres to the intestinal wall and emits a toxic material that can dissolve it, causing bloody diarrhea, extreme cramping and, in severe cases, kidney failure and death.
Cooking kills bacteria
The best way to kill E. coli on fresh greens is to thoroughly cook them. Washing alone may not remove the bacteria.
At this point in the growing season, lettuce production in the United States has largely moved away from Central California into Imperial County and Arizona.
News of the latest developments came, coincidentally, as leaders of the state's produce industry on Friday were proposing measures to ensure safety and boost consumer confidence following the outbreaks.
At a state Department of Food and Agriculture hearing in Monterey on Friday, growers proposed a state-issued "seal of approval" to identify leafy greens grown and processed under certain standards, which are yet to be developed.
"This is an industry-led initiative," said Jim Bogart, president and general counsel for the Grower-Shipper Assn. of Central California, although the program would be overseen by the Food and Agriculture Department.
The program, at least initially, would be voluntary, but industry leaders said pressure from both retailers and consumers would force growers and handlers -- the middlemen who bring greens from the farms to retailers -- to participate.
Participants would be subject to mandatory outside inspections by federal and state authorities and would lose their seal of approval if infractions were found, the plan's backers said.
The standards would be developed by a board of industry representatives working with state and federal regulators and university agricultural scientists, they said.
But state Sen. Dean Florez (D-Shafter) testified that stronger measures were needed.
"You have a skeptical public, and an even more skeptical Legislature, who looks at this as a public health issue," he said in an interview afterward
Florez said he would introduce a package of food safety bills next week that would give health officials the power to enforce regulations over the industry, including penalizing growers.
"We want to give consumers confidence that what goes from the farm to the fork is governed by some very strict laws," he said.
Caroline Smith DeWaal, director of food safety for the Center for Science in the Public Interest, agreed that regulations should be mandatory and enforced by government.
"Voluntary systems haven't proven terribly effective in ensuring food safety uniformly," DeWaal said. "Certainly some growers are going to utilize the very best standards. But growers who don't will still be able to sell their products, and probably sell them cheaper."
Times staff writer Jerry Hirsch contributed to this report.