You may want to put down that fork and step away from that salad. Consumer Reports is issuing a warning after a multi-state outbreak of E. coli infections.

The Center for Disease Control and Prevention (CDC) has confirmed that it is investigating an outbreak of E. coli infections that have occurred in Canada and 13 states, including New York. Five people in the U.S. have been hospitalized and 1 has died, according to the CDC.

The Canadian Health System has confirmed that romaine lettuce is the source of the infections in Canada. While the CDC has conducted tests that suggest the infected individuals have a common source of infection, they are unable to confirm that romaine lettuce is the culprit.

Consumer Reports says that because the particular strain of E. coli that has been identified can cause illness, kidney disease, and even death, they recommend avoiding romaine lettuce.

According to Consumer Reports:

(Our) food safety experts are advising that consumers stop eating romaine lettuce until the cause of the outbreak is identified and the offending product is removed from store shelves.

“Even though we can’t say with 100 percent certainty that romaine lettuce is the cause of the E. coli outbreak in the U.S., a greater degree of caution is appropriate given that lettuce is almost always consumed raw,” says James Rogers, Ph.D., director of Food Safety and Research at Consumer Reports.

If you have eaten food contaminated with E. coli, you might experience severe stomach cramps, diarrhea (often bloody), and vomiting. You may have a slight fever. These symptoms can start anywhere from 1 to 10 days after eating the contaminated food.

The CDC recommends seeing a doctor if you have a high fever, bloody diarrhea, or severe vomiting, or if diarrhea lasts longer than 3 days.