(HealthDay)—You may want to think twice about that Caesar salad.
As a recent outbreak of serious illness from the E. coli stomach bug continues to spread across the United States, experts say romaine lettuce grown in Arizona could be the culprit.
Since the last update on Tuesday, "18 more ill people have been reported, bringing the total to 35 ill people in 11 states," the U.S. Centers for Disease Control and Prevention said in a news release issued Friday.
Overall, 22 people have been hospitalized with the E. coli O157:H7 strain, across 11 states. No deaths have occurred, but in three cases patients developed a type of kidney failure called hemolytic uremic syndrome, the CDC said.
Illnesses include nine cases in Pennsylvania, eight cases in Idaho, seven cases in New Jersey, two cases each in Connecticut, New York and Ohio, and one case each in Illinois, Michigan, Missouri, Virginia and Washington.
The CDC says that, based on its investigation, "chopped romaine lettuce from the Yuma, Arizona growing region could be contaminated with E. coli O157:H7 and could make people sick."
The agency's advice? "People who have store-bought chopped romaine lettuce at home, including salads and salad mixes containing chopped romaine lettuce, should not eat it and should throw it away, even if some of it was eaten and no one has gotten sick."
And the CDC adds that restaurants should avoid buying and serving romaine lettuce from the Yuma, Arizona region.
As for consumers, "before buying romaine lettuce at a grocery store or eating it at a restaurant, confirm that it is not chopped romaine lettuce from the Yuma growing region. If you cannot confirm the source of the lettuce, do not buy or eat it," the CDC said.
The agency stressed that E. coli illness can be very serious, even deadly.
Usually, illness sets in "an average of 3 to 4 days after swallowing the germ. Most people get diarrhea (often bloody), severe stomach cramps and vomiting," according to the CDC.
For most, recovery will occur within a week, but more severe cases last longer.
"Talk to your doctor if you have symptoms of an E. coli infection and report your illness to your local health department," the agency said.
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Find out more about E. coli illness at the foodsafety.gov.