U.S. officials think they've traced the source of the lettuce involved in latest E. coli outbreak

The U.S. Food and Drug Administration believes it has traced the source of the latest E. coli outbreak. The agency said Monday the romaine linked to the outbreak appears to be from the California's Central Coast region. It said romaine from elsewhere should soon be labelled with harvest dates and regions so people know it's safe to eat.

The Canadian Food Inspection Agency (CFIA) said it is continuing its own investigation in conjunction with the Public Health Agency of Canada (PHAC) and Health Canada (HC) into the current outbreak of E. coli O157. But it has advised the Canadian food industry, including importers, not to import romaine lettuce from the suspect areas identified by the FDA until further notice.

The CFIA is also implementing additional control measures to ensure products from California's Central Coast region are not being admitted to Canada, including greater scrutiny of product destined for this country.

Twenty-two people in Ontario, Quebec, and New Brunswick have been sickened by E. coli since October. Forty-three people in 12 U.S. states have also been sickened.

Labelling changes 

In the U.S., the FDA is advising people not to eat romaine that doesn't have clear labelling information stating where the produce is from. For romaine that doesn't come in packaging, grocers and retailers are being asked to post the information by the register.

Romaine harvesting recently began shifting from California's Central Coast to winter growing areas, primarily Arizona, Florida, Mexico and California's Imperial Valley. Those winter regions weren't yet shipping when the illnesses began. The FDA also noted hydroponically grown romaine and romaine grown in greenhouses aren't implicated in the outbreak.

The labelling arrangement was worked out as the produce industry called on the FDA to quickly narrow the scope of its warning so it wouldn't have to waste freshly harvested romaine. An industry group said people can expect to start seeing labels as early as this week. It noted the labels are voluntary, and that it will monitor whether to expand the measure to other leafy greens and produce.

The FDA said the industry committed to making the labelling standard for romaine and to consider longer-term labelling options for other leafy greens.

Robert Whitaker, chief science officer of the Produce Marketing Association, said labelling for romaine could help limit the scope of future alerts and rebuild public trust after other outbreaks.

"Romaine as a category has had a year that's been unfortunate," Whitaker said.

The FDA still hasn't identified a source of contamination in the latest outbreak. 

Even though romaine from the Yuma, Ariz., region is not implicated in the current outbreak, it was blamed for an E. coli outbreak this spring that sickened more than 200 people and killed five. Contaminated irrigation water near a cattle lot was later identified as the likely source.

Leafy greens were also blamed for an E. coli outbreak last year. U.S. investigators never specified which salad green might be to blame for those illnesses, which happened around the same time of year as the current outbreak. But Canadian officials identified romaine as a common source of illnesses in Canada.