Americans have been warned not to eat romaine lettuce amid an E.coli outbreak that has caused illness in 11 states.
The Centre for Disease Control and Prevention (CDC) says consumers who have any type of romaine lettuce in their home “should not eat it and should throw it away, even if some of it was eaten and no one has gotten sick”.
No deaths have been reported, but 32 people have become ill after they were infected with Shiga toxin-producing E. coli O157:H7.
Thirteen of them required hospital treatment with one person suffering kidney failure.
Illnesses started on dates ranging from 8 October to 31 October.
Canada has also reported 18 cases of illness from the same strain.
The CDC says it is working to identify the source of the outbreak.
Restaurants have been told not to serve any romaine lettuce, and advice to consumers is to “wash and sanitise drawers or shelves in refrigerators where romaine was stored”.
The CDC says: “If you do not know if the lettuce is romaine or whether a salad mix contains romaine, do not eat it and throw it away.”
Its website says: “CDC is advising that US consumers not eat any romaine lettuce, and retailers and restaurants not serve or sell any, until we learn more about the outbreak.
“This investigation is ongoing and the advice will be updated as more information is available.”
E.coli (full name Escherichia coli) is a type of bacteria common in human and animal intestines.
It forms part of the normal bacteria that exist in the bowel, but some strains, including the O157 affecting America, produce Shiga toxins that can cause severe illness.