Update: On June 28, 2018, the Centers for Disease Control and Prevention declared this E. coli outbreak officially over. 

U.S. food-safety and health officials declared an end Thursday to a lethal E. coli outbreak associated with leafy greens. In light of this development, Consumer Reports is no longer recommending that consumers avoid romaine lettuce.

After nearly two months of investigation, the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) jointly declared an end to the outbreak. At least 66 people across the U.S and Canada became ill, 22 were hospitalized, and two died during November and December.

The FDA and CDC were not able to identify a specific type of leafy green, the location where the produce was grown, or the supplier. As a result, the agencies did not make any specific suggestions about foods to avoid during the outbreak. The agencies said that no new illnesses were reported since Dec. 12.

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The FDA said it would continue “to work with federal, state, and local partners" to determine which leafy greens made people ill and where people bought the greens. The agency says it wants to identify the distribution chain and any common foods or points where that food might have become contaminated.

Consumer Reports advised avoiding romaine lettuce in early January. Canadian health authorities had announced romaine was the cause of the outbreak in that country and lab testing showed that the Canadian E. coli strain was almost identical to the strain found in the U.S.

“It’s encouraging that since mid-December there have been no more reports of people getting sick from this dangerous strain of E. coli,” says James E. Rogers, Ph.D., director of food safety research and testing at Consumer Reports. The strain, E. coli O157:H7, produces a particularly dangerous toxin that can cause kidney failure.

“Given that there don't seem to be any new cases for the past few weeks, the Canadian government declared the outbreak over earlier this month, and the FDA and CDC have now followed suit, we [Consumer Reports] are no longer recommending that consumers avoid romaine lettuce,” Rogers says.

Earlier this month the CDC declared that: “Leafy greens typically have a short shelf life, and since the last illness started a month ago, it is likely that contaminated leafy greens linked to this outbreak are no longer available for sale.”

But because there was no confirmed source, it was difficult to know whether further contamination could occur, Rogers said at the time. “Without knowing exactly what caused this outbreak, we risk seeing a new batch of tainted product come onto the market. For instance, if the equipment at a processing plant is contaminated with E. coli O157:H7, new product could become a source of further infections.”

Rogers said Thursday that Consumer Reports will continue to monitor the situation and the ongoing investigation.

Public Concerns

Federal investigators did not publicly share information on the problem for several weeks after the last known illness was reported, and even then information on this deadly outbreak was scant.

Food policy advocates, as well as legislators such as Rep. Rosa DeLauro (D-CT) and Rep. Louise Slaughter (D-NY), said they were troubled that the FDA and CDC were not quicker to alert Americans to the outbreak, as the Canadian health agency did.

Consumer Reports’ food-policy team shares these concerns.

“We’re pleased that the FDA is continuing to try and track down the source of this outbreak,” says Jean Halloran, director of food policy initiatives at Consumers Union, the policy and mobilization division of Consumer Reports. “However, this situation revealed significant problems with the way government agencies respond to foodborne illness. Investigations need to proceed more quickly, CDC and FDA need to provide more information about what they are doing, and consumers need to hear sooner what they can do to protect themselves.”