The Public Health Agency of Canada (PHAC) said the lettuce, distributed by FreshPoint Inc. to some KFC and KFC-Taco Bell is the most probable cause of the E.coli O157:H7 illness.
Due to the short shelf life, contaminated products are unlikely to still be available and the products were not distributed to grocery stores, said PHAC.
The grower of the contaminated shredded lettuce has still not been confirmed.
The Canadian Food Inspection Agency (CFIA) has traced the lettuce to its origin in California and is in the process of verifying that appropriate food safety controls were followed at each step of production, processing and distribution.
There are 10 cases in Nova Scotia and Ontario and six cases in New Brunswick.
Distribution of the two products packaged for use by KFC occurred in New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island and Quebec.
The majority of cases are recovering or have recovered but the outbreak has resulted in 11 hospitalizations of people from ages two years to 83 with dates of illness ranging from 22 December to 3 January.
“The Public Health Agency of Canada continues to lead the coordination of the investigation into this outbreak in close collaboration with its health and food safety partners,” said the agency.
“E.coli O157 food-borne illnesses are not uncommon in Canada. In recent years, an average of about 440 cases of this type of E.coli infection was reported annually in Canada.”