Canadian officials say an E. coli outbreak linked to romaine lettuce from Arizona has ended with only eight confirmed cases in their country. In the United States, where at least five people have died in the outbreak, officials have not updated the public for weeks. 

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The U.S. outbreak investigators are apparently continuing their efforts, but neither the Food and Drug Administration nor the Centers for Disease Control and Prevention have released any new information since June 1. At that point 197 people across 35 states had been confirmed with infections from the outbreak strain of E. coli O157:H7. 

Of the U.S. victims for whom complete information was available, 89 had required hospitalization and five had died, according to the CDC’s update more than three weeks ago. The CDC also reported 26 people had developed a type of kidney failure called hemolytic uremic syndrome (HUS).

In Canada the investigation is officially over, according to the Public Health Agency of Canada. 

“Based on the evidence from the U.S. outbreak investigation, and the information provided by individuals who became sick, the likely source of the outbreak in Canada was identified as contaminated romaine lettuce, but the source of contamination was not identified,” Canadian public health officials reported.

“Given that there have not been any new illnesses reported in the investigation since late April 2018, the Canadian outbreak appears to be over and the outbreak investigation has been closed.”

The eight victims in Canada all reported eating chopped romaine lettuce in the days before becoming sick. They all said the romaine was in packaged salads from grocery stores or in salads from restaurants. Two of the Canadians reported traveling to the United States and eating romaine there before becoming ill. Canadians became sick between March 18 and April 22.

In the United States, illness onset dates that were known as of June 1 ranged from March 13 through May 12.

“State and local health officials continue to interview ill people to ask about the foods they ate and other exposures they had before they became ill. Of the 158 people interviewed, 140 (89%) reported eating romaine lettuce in the week before their illness started,” according to the CDC’s June 1 update.

The CDC and FDA began warning the public to avoid romaine lettuce from the Yuma, AZ, growing area on April 13. Individual growers and produce associations reported the last romaine of the season shipped out of Yuma on April 16.

Investigators from the FDA and state departments of agriculture have had difficulties tracing the implicated romaine back to specific growers, packers, processors or distributors. As of the June 1 update from FDA, it remained unknown who grew the implicated romaine and how it became contaminated.

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