SAN FRANCISCO (CBS SF) -- Federal health officials Friday warned consumers to not eat romaine lettuce from the Yuma, Arizona growing region because a growing E. coli outbreak.
The Centers For Disease Control And Prevention had issued a previous warning, but Friday's announcement went much further.
"Do not buy or eat romaine lettuce at a grocery store or restaurant unless you can confirm it is not from the Yuma, Arizona, growing region," the federal health officials said. "Unless the source of the product is known, consumers anywhere in the United States who have any store-bought romaine lettuce at home should not eat it and should throw it away, even if some of it was eaten and no one has gotten sick."
The CDC warning continued: "Product labels often do not identify growing regions; so, throw out any romaine lettuce if you're uncertain about where it was grown."
The expanded warning was based on information from newly reported illnesses in Alaska. Ill people in Alaska reported eating lettuce from whole heads of romaine lettuce from the Yuma, Arizona growing region.
Romaine Lettuce grown in the Yuma region has been linked to an E. coli outbreak that has infected 53 people in 16 states. Of those victims, 31 people have been hospitalized, including five people who have developed a type of kidney failure called hemolytic uremic syndrome.
Symptoms of this strain of E. coli include severe stomach cramps, vomiting, and diarrhea, which is often bloody, officials said. Anyone with these symptoms should see a health provider immediately and report their infection to local departments of health and social services.
Infections from these bacteria often take three to four days to develop. Most are gone within a week, but some can last longer and be more severe, the CDC said.
E. coli are a diverse family of bacteria that can be found in the environment, in foods and in the intestines of people and animals. Most strains are harmless. To avoid becoming infected with a harmful strain, the CDC recommends using proper hygiene; cooking meat at proper temperatures; avoiding raw milk, unpasteurized dairy products and juices; and not swallowing water when swimming.
Since lettuce is suspected to be the cause of the current outbreak, would it help to wash your greens before eating? No, said Ian Williams, chief of the CDC's Outbreak Response and Prevention Branch.
"This bacteria can actually get inside the lettuce leaf," he said. "Washing it doesn't make it safe.
Fortunately, no deaths have been reported. The CDC said the investigation into the source of the outbreak was continuing and it would provide updates when more information is available.
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