SAN FRANCISCO (CBS SF) -- Federal health officials announced Wednesday that a multistate E. coli outbreak linked to romaine lettuce grown in Arizona has spread to 31 new victims, three new states and was proving to be a very potent strain of bacteria.
The Centers for Disease Control and Prevention (CDC) said 84 people had fallen ill in 19 states. Of those, 42 people have been hospitalized and nine of those have developed a type of kidney failure called hemolytic uremic syndrome.
"This is a higher hospitalization rate than usual for E. coli O157:H7 infections, which is usually around 30 percent," the CDC said in a press release. "Health officials are working to determine why this strain is causing a higher percentage of hospitalizations."
So far there have been no deaths reported.
The CDC had issued a warning last week, telling consumers to avoid eating romaine lettuce.
"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."
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.
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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