Romaine lettuce still sits on the shelves at a market in Simi Valley, Calif. (Mark J. Terrill/AP)

Health officials in the United States and Canada told people Tuesday to stop eating romaine lettuce because of a new E. coli outbreak.

The outbreak has sickened 32 people in 11 states and 18 people in the Canadian provinces of Ontario and Quebec.

The bacteria identified is different from the one linked to romaine earlier this year. Scott Gottlieb, commissioner of the Food and Drug Administration, said supermarkets and restaurants should remove romaine until the source of the contamination can be identified. Consumers are also advised to throw out any romaine they have at home.

Gottlieb said the FDA wanted to issue a warning before people gathered for Thanksgiving meals, where the potential for exposure could increase.

“One of the problems with produce is that it can be very hard to trace back,” said Sarah Sorscher, deputy director of regulatory affairs at the Center for Science in the Public Interest.

That can mean the entire industry becomes implicated in outbreaks, even if not all products are contaminated. She said washing contaminated lettuce will not ensure that harmful germs are killed.

Infections from E. coli can cause symptoms including severe stomach cramps, diarrhea and vomiting. Most people recover within a week, but some illnesses can last longer and be more severe.

No deaths have been reported in the current outbreak, but 13 people in the United States and six in Canada have been hospitalized. The last reported U.S. illness was on October 31, and the most recent illness in Canada was this month.

Most romaine sold this time of year is grown in California, Gottlieb said. The romaine lettuce linked to the E. coli outbreak earlier this year was from Yuma, Arizona. Contaminated irrigation water appeared to be the source of that outbreak, which sickened about 200 people and killed five.

Health officials have also been reminding people to properly handle and cook their Thanksgiving birds amid a widespread salmonella outbreak linked to raw turkey.

But unlike with romaine lettuce, regulators are not warning people to avoid turkey. Salmonella is not prohibited in raw meat and poultry, and the Agriculture Department, which overseas raw meat, said cooking should kill any salmonella.

— Associated Press