"At this time, no common grower, supplier, distributor, or brand has been identified", the Centers for Disease Control and Prevention (CDC) says on its website, though health officials recommend throwing away any store-bought chopped romaine lettuce you've purchased recently.
About 53 people have been reported sickened in 16 states since March 13, the CDC said. Thirty-one people required hospitalization, including two people who developed a type of kidney failure called hemolytic uremic syndrome.
No deaths have been reported, the CDC said. Food-poisoning cases linked to the lettuce have been reported from coast to coast, including Washington state, New York, Connecticut, Pennsylvania, New Jersey, Idaho, Ohio, Illinois, Michigan, Missouri, and Virginia.
Symptoms of E. coli O157 include diarrhea (sometimes bloody), and abdominal pain. "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. The C.D.C. has said that the current E. coli outbreak does not appear to be related to another that began late previous year and was traced more generally to "leafy greens".
-Before purchasing romaine lettuce at a grocery store or eating it at a restaurant, confirm with the store or restaurant that it is not chopped romaine lettuce from the Yuma, Arizona growing region.
Pennsylvania was home to 12 people infected in the outbreak, more than any other state. Due to the four-day shelf life, the products should no longer be available in stores.
There have been no recalls of romaine lettuce so far since people began reporting illnesses related to E. coli.
The CDC is urging consumers to throw out their chopped romaine lettuce immediately.
In the meantime the CDC guidance for consumers remains unchanged.
How many people have been sickened by the romaine lettuce E. coli outbreak?The CDC said Wednesday that all USA consumers should throw away any previously purchased chopped romaine lettuce, including in pre-made salads or salad mixes, even if it's been consumed with no resulting illness. "If you do not know if the lettuce is romaine, do not eat it and throw it away", the CDC states.
Written by Nicole Chavez for CNN.