E. coli outbreak: What Canadians should know about washing, eating lettuce

NOTE: This story was originally published on Dec. 15, 2017. Since then, there has been a new outbreak of E. coli related to romaine lettuce, announced in Nov. 2018. The story below contains information about E. coli, romaine lettuce contamination and safe food handling.

One person has died amid an E. coli outbreak, the Public Health Agency of Canada confirmed on Dec. 14, 2017.

The outbreak in five provinces — Ontario, Quebec, New Brunswick, Nova Scotia and Newfoundland and Labrador — has led to 30 cases being investigated.

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Health officials said those who became sick all reported eating romaine lettuce before the illness. But the exact source of the lettuce hasn’t been tracked down.

What exactly happens during an E. coli illness?

Symptoms of E. coli infection include nausea, vomiting, headache, fever, severe stomach cramps and watery or bloody stool.

Most people recover in a few days but some can develop life-threatening illnesses that can cause death.

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Here’s what consumers should know about the outbreak, and how to stay safe:

How does lettuce become contaminated?

Jason Tetro, a visiting scientist at the University of Guelph in Ontario, explained that the bacteria is typically not found in produce such as lettuce. Instead, it’s in the water that’s used to irrigate produce on farms. For example, he said the water from a nearby river could be contaminated with manure from cows on the farm.

“That can get onto the lettuce, and eventually end up in a person,” Tetro told Global News.

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But Tetro noted that tracing the origin of an E.coli outbreak is incredibly difficult for this reason — especially if it isn’t isolated to a specific store, restaurant or province.

“We may never know what the actual source was, and instead, our only recourse may be to do a recall.”

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What is the best way to wash lettuce?

Not being able to trace back the source of the outbreak can be tricky for those deciding which lettuce to buy. But Tetro explained that if lettuce is properly washed, it can minimize the risk of contamination.

“If you are buying lettuce, romaine or otherwise, make sure each leaf is given a good washing under warm to hot water,” he advised.

Using “friction,” or rubbing the leaves with hands, is one way of making sure any bacteria is washed off.

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Does pre-washed lettuce need to be rinsed?

The shorter answer, according to Tetro, is yes.

“Let’s put it this way, did you see the person who washed it? No,” he said, explaining that consumers can never be too sure of how the produce was cleaned.

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“It’s much better for your own safety that you do something yourself.”

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Tetro advised that overall, Canadians buying lettuce (or any other food) should exercise basic food safety rules and use common sense.

“When you finish handling food make sure that there’s no cross-contamination with meats and other things, especially if it’s fresh produce. It’s not related to this case, but just to make sure you stay safe.”

— With files from The Canadian Press