LOS ANGELES (Reuters) - McDonald's Corp, Wal-Mart Stores Inc and other restaurant and grocery chains have stopped selling certain tomatoes as U.S. health officials work to pinpoint the source of a Salmonella outbreak.
The U.S. Food and Drug Administration on Saturday warned U.S. consumers that the outbreak was linked to eating certain raw red plum, red Roma, and red round tomatoes, and products containing these tomatoes.
The agency, which first alerted consumers to the risk on June 3, has not yet identified the source of the contaminated tomatoes.
"That could be a matter of a few days, it could be longer than that," FDA Commissioner Andrew von Eschenbach said at a news conference at a testing facility in Irvine, California.
As of Saturday, the FDA said there had been 145 reported cases, including at least 23 hospitalizations, related to the outbreak since mid-April. The infections, which have struck most often in New Mexico and Texas, were caused by Salmonella Saintpaul, an uncommon type of the bacteria.
Salmonella bacteria are frequently responsible for food-borne illnesses. Symptoms generally appear within 12 to 72 hours after eating infected food and include fever, diarrhea, nausea, vomiting and abdominal pain.
Infants, the elderly and those with weakened immune systems are more likely than others to develop severe illness, which can be deadly unless treated with antibiotics.
The FDA has said that it is safe to eat cherry tomatoes, grape tomatoes and tomatoes sold with the vine still attached, or tomatoes grown at home.
The agency has said it doesn't know where the tomatoes originated, but it named several states that it does not believe are connected to the outbreak, including California, which is the second largest tomato producing state, behind Florida.
The full list is available here#retailers.
Ed Beckman, president of the California Tomato Farmers, said that at the time of the outbreak Florida and Mexico were the biggest suppliers of tomatoes to the United States.
Neither Mexico, nor Florida was included in the FDA's list of states.
A spokesman for the Florida Tomato Committee, a marketing group that represents the industry, could not be reached immediately for comment.
Representatives for tomato producers in Mexico's largest tomato-growing state of Sinaloa could not be reached immediately for comment, nor could spokesmen for Mexico's agriculture ministry.
McDonald's, the world's largest restaurant chain, said on Monday it has temporarily stopped serving sliced tomatoes on its sandwiches in the United States.
"This is a precautionary measure only. McDonald's has not experienced any related issues to date," the company said in a statement.
McDonald's said it will continue to serve grape tomatoes in its salads.
According to a notice posted to Wal-Mart's Web site on Thursday, the company removed products identified in the FDA alert.
Burrito chain Chipotle Mexican Grill also said it has put a temporary stop to serving tomatoes.
"Like many other restaurants, we've pulled tomatoes as a precautionary measure and will not begin serving them again as long as there remains any concern about the tomato supply in this country," Chipotle spokesman Chris Arnold said on Monday.
A spokesman for pizza seller Papa John's said the warning does not affect the chain because it does not serve uncooked tomatoes. Cooking kills the bacteria that causes Salmonella.
Grocers Supervalu and Winn Dixie Stores Inc said they have stopped selling tomatoes that the FDA has warned should not be consumed.
A spokeswoman for Target Corp said the retailer has pulled the tomatoes from shelves at its SuperTarget stores that offer groceries.