Three more Canadian cases have been confirmed in the current E. coli outbreak associated with romaine lettuce, the Public Health Agency of Canada said on Friday.That brings the total number of people who have fallen ill in this country to 22, including four cases in Ontario, 17 in Quebec and one in New Brunswick. The agency said there is no evidence that other parts of Canada have been affected. The outbreak has also sickened more than 30 people in the U.S.The romaine lettuce contaminated with E. coli O157 likely came from California, the head of the U.S. Food and Drug Administration (FDA) said on Friday. That conclusion is “based on growing and harvesting patterns,” FDA Commissioner Dr. Scott Gottlieb tweeted. “The goal now is to withdraw the product that’s at risk of being contaminated from the market, and then re-stock the market,” he said.However, in a telephone briefing with media on Friday, the Canadian Food Inspection Agency said that although it was incorporating the information from the FDA into its investigation, it could not yet confirm whether or not the romaine lettuce making Canadians sick was grown in California.UPDATE ON OUTBREAK: The romaine implicated in the current outbreak is likely from California based on growing and harvesting patterns. The goal now is to withdraw the product that’s at risk of being contaminated from the market, and then re-stock the market…..—@SGottliebFDAGottlieb said the FDA wants “to help unaffected growers get back into production,” noting that romaine lettuce would soon be harvested from other growing regions in the U.S., including Florida and Arizona.The agency also wants to make more specific product labelling “the new standard” to help trace food back to the source, he said. The FDA was “working with growers and distributors on labelling produce for location and harvest date and possibly other ways of informing consumers.” Labelling has proven to be a challenge in investigating food contamination, Matthew Wise, deputy branch chief for outbreak response at the U.S. Centers for Disease Control and Prevention, told CBC on Friday. “One of the things that we don’t sort of see on packaging is where a leafy green product was grown,” Wise said. “A lot of times those bags are listed with … the location of the corporate headquarters from the company or something like that. He said that makes it “almost impossible” for someone looking at a bag of lettuce to know whether, for example, it was grown in Arizona, California, Florida or Texas.