A worker harvests romaine lettuce in Salinas, Calif on Aug. 16, 2007. Some restaurant chains have stopped serving dishes with romaine lettuce amid a deadly E. coli outbreak linked to the leafy vegetable.THE CANADIAN PRESS/AP, Paul Sakuma

What you need to know: The lettuce-linked E. coli outbreak

What consumers should know about the romaine lettuce-linked E. coli outbreak

Since mid-November, dozens of people have become ill and two people have died in Canada and the U.S. due to infection with E. coli 0157:H7, which has been linked in this country to contaminated romaine lettuce. Here is a primer on E. coli and what consumers can do to avoid becoming sick:

What is E. coli? Escherichia coli bacteria normally live in the intestines of healthy people and animals and are typically harmless. But infection with the O157:H7 strain, which produces a shiga toxin, can cause severe abdominal cramps, bloody diarrhea and vomiting. Healthy adults usually recover within a week, but young children and older adults have an increased risk of developing a life-threatening type of kidney failure called hemolytic uremic syndrome.

How does contamination occur? E. coli can be shed in the feces of cattle, poultry and other animals, polluting water used to irrigate crops and the soil where fruits and vegetables are grown. Leafy greens, such as lettuce and spinach, can become contaminated during and after harvest from handling, storing and being transported. An individual infected with E. coli also can transmit it to other people.

“This strain of E. coli causes more outbreaks than all other strains combined, so it’s the big problem,” said Herb Schellhorn, a microbiologist at McMaster University in Hamilton, who specializes in the study of E. coli and other water- and food-borne pathogens.

What’s the source of this outbreak? A Canadian Food Inspection Agency-led investigation has determined that romaine lettuce is at the heart of the E. coli outbreak in five eastern provinces, but the source of the produce has not yet been identified. The U.S. Centers for Disease Control has concluded the E. coli involved in 17 cases in 13 states has a closely related genetic signature as the strain behind Canada’s 41 cases, but has not confirmed the food source. One person in Canada and one in the U.S. have died.

“This time of year, most of our lettuce will come from southern places … so if it’s affecting both countries, it may be from California or Mexico or other countries that produce romaine lettuce,” said Schellhorn. ”But it also can be contaminated during the processing by individuals who are infected or if there was fecal contamination introduced at some point in the distribution (process).”

He said the longer it takes to pin down the source of adulteration, the more difficult it will become over time, given that romaine is a perishable item.

“It’s not like it’s frozen and we can go into meat lockers and test food materials for contamination. Depending on how it was contaminated, if it was in one large place and it’s the water that was contaminated, that could have implications for other food materials that might have been exposed.”

While that ”doesn’t appear to be the case” with this outbreak, Schellhorn said E. coli. 0157:H7 is highly infectious and exposure to only a very small amount can cause disease.

What can consumers do? The Public Health Agency of Canada says on its website that thoroughly washing potentially contaminated romaine lettuce — or any other fresh produce — in water can remove the bacteria.

But Schellhorn suggests it’s better to be safe than sorry.

Not only does he advise not purchasing romaine lettuce currently on grocery store shelves, he suggests consumers toss out any they have in the fridge.

“It’s not worth taking a chance … Lettuce isn’t that expensive, it has a short shelf life anyway,” he said.

“I think I would just throw it out.”

Sheryl Ubelacker, The Canadian Press

Like us on Facebook and follow us on Twitter.

Just Posted

United for Saanich among 62 slates running across British Columbia

The only communities outside Greater Victoria and the Lower Mainland featuring slates are Nelson and Sechelt

Puff, puff, pass: Cannabis is officially legal across Canada

B.C. has only one bricks-and-mortar marijuana store

PHOTOS: Celebration, heartbreak from weekend World Rowing in Sidney

On-water photographers capture the action for coastal rowing’s North American debut

10 things still illegal in the new age of recreational cannabis

Pot is legal – but there are still a lot of rules, and breaking some could leave you in jail

North Saanich residents commended for bravery in crash response

Six residents did not hesitate after serious single-vehicle crash

VIDEO: How to roll a joint

The cannabis connoisseur shares his secrets to rolling the perfect joint

Advance voting begins Oct. 10 in Greater Victoria

The polls open at 8 a.m. for the 2018 municipal election with the general election taking place Oct. 20

Find your future at Black Press career fair in Victoria

More than 70 booths expected at Bay Street Armoury on Oct. 25

1,000 needles pulled from Cowichan River

Duncan area cleanup project nets three huge truckloads of garbage

Harry and Meghan bring rain to drought-stricken Outback town

Prince Harry and his wife Meghan are on day two of their 16-day tour of Australia and the South Pacific.

Demand for legalized cannabis in early hours draws lineups, heavy web traffic

Government-run and privately operated sales portals went live at 12:01 a.m. local time across Canada, eliciting a wave of demand.

Killer-rapist Paul Bernardo set to make parole pitch today

Paul Bernardo, whose very name became synonymous with sadistic sexual perversion, is expected to plead for release on Wednesday.

Hero campaign raises $1.1 million for Canada non-profits

Lowe’s Canada Heroes campaign was held throughout September

Scope of Hurricane Michael’s fury becomes clearer in Florida Panhandle

Nearly 137,000 Florida customers remain without power from the Gulf of Mexico to the Georgia border

Most Read