The Centers for Disease Control and Prevention is investigating whether romaine lettuce is the source of a deadly E. coli outbreak.

In the past two months, 58 people in the U.S. and Canada have become ill and one person in the U.S. has died in the multi-state outbreak, according to Consumer Reports. The CDC has identified 17 cases of illness.

The CDC reported that the infection has been found in 13 states and Canada. Those states are California, Connecticut, Illinois, Indiana, Michigan, Nebraska, New Hampshire, New York, Ohio, Pennsylvania, Virginia, Vermont and Washington.

The outbreak started on dates from Nov. 15 through Dec. 8, according to the CDC.

Canadian health authorities identified romaine lettuce as the source of the outbreak in Canada, but the investigation in the U.S. is still ongoing. State and local public health officials are interviewing sick people to determine what they ate in a week before their illness started.

Even though the CDC hasn't confirmed a link with romaine lettuce, Consumer Reports is still recommending that people stop eating it until the cause of the outbreak is determined.

"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,” said James Rogers, Ph.D., Director of Food Safety and Research at Consumer Reports in their report.

This strain of E. coli produces a toxin that, in some cases, can lead to serious illness, kidney problems and even death.