New Brunswick

Prof 'shocked' by New Brunswick medical officer's advice about avoiding E. coli

When it comes to E. coli on your romaine lettuce, washing won't cut it, says professor and food microbiologist.

Washing romaine lettuce isn't the answer when there's a risk of E. coli, says microbiologist Keith Warriner

Keith Warriner, a University of Guelph microbiologist specializing in food safety, says both Canadian and U.S. regulators should issue a mandatory recall of romaine lettuce because of recent E. coli cases. (University of Guelph)

When it comes to your romaine lettuce, don't count on washing to remove E. coli, says a professor and food microbiologist. 

"We've known for years now that washing doesn't cut it," said Keith Warriner of the University of Guelph.

Warriner said he was "shocked" by advice the public got this week from Dr. Jennifer Russell, New Brunswick's chief medical officer of health, after people got sick from E. coli in Ontario, Quebec and New Brunswick.

Russell advised people to throw away their romaine lettuce. But if they decided to consume the lettuce, she said, they should wash it under cool, running water. 

Warriner said washing is too risky.  

Just leave romaine lettuce for now and try iceberg or leafy greens.- Keith Warriner, University of Guelph

With E. coli O157, it only takes 10 to 100 cells to cause illness, he said.

"To put it in perspective, you can get about a billion cells on a pin head," said Warriner, who doesn't eat lettuce himself.

"And the thing about washing is that it can't get into the grooves between plant cells, where E.coli can reside."

Grocery stores have already pulled romaine lettuce from their shelves, but the Canadian Food Inspection Agency hasn't issued a recall.

A blanket" recall — making it mandatory for all stores and restaurants to stop selling or serving romaine lettuce, regardless of the source — should be issued, Warriner said.

Illness in 3 provinces

Earlier this week, a case of E. coli was confirmed in New Brunswick and linked to contaminated lettuce, making 19 confirmed cases in Canada from the same strain of the bacteria.  

If ingested, Warriner said, E.coli can be deadly because it produces a shiga toxin that causes the kidneys to break down. 

A person infected with E. coli is typically treated with antibiotics, but Warriner said this actually produces even more shiga toxins.  

Warriner said people should just avoid romaine altogether.

"It's simply not worth the risk of kidney failure conditions. At the moment nobody is really sure what's contaminated, what isn't."

Where does it come from?

E. coli bacteria are naturally found in the intestines of farm animals. Contamination of vegetables and fruit can occur when they come in contact with animal feces. Most forms of the bacteria are harmless. 

This is the third outbreak of E. coli related to lettuce in North America this year.

Earlier this week, a case of E. coli was confirmed in New Brunswick and was linked to contaminated lettuce. (Andrew Caballero-Reynolds/AFP/Getty Images)

"Just leave romaine lettuce for now and try iceberg or leafy greens," Warriner said.

The Health Department has said symptoms of E. coli appear within four days of infection and include frequent diarrhea, often bloody, and stomach cramps.

Symptoms can last up to 10 days.

With files from Information Morning Fredericton, Nicole Ireland


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