The Centers for Disease Control and Prevention is warning consumers not to buy or eat romaine lettuce at a grocery store or a restaurant because of an outbreak of E. coli from romaine lettuce traced to the Yuma, Arizona growing area. This guidance applies to whole heads and hearts of romaine lettuce, chopped romaine and salads and salad mixes that contain romaine.

53 people have been infected with the strain of E. coli O157:H7 which caused 31 hospitalizations and five cases of a type of kidney failure called hemolytic uremic syndrome. Most product labels don't identify the growing region, so the CDC is advising people to throw out any romaine lettuce in their fridge, even if part of it has been eaten with no ill effects.

The reason for the wide ranging warning is because consumers anywhere in the United States can have romaine lettuce from the Yuma, Arizona growing area. The CDC has not been able to trace the outbreak to a specific grower, supplier, distributor or brand.