A joint investigation between the Canadian Food Inspection Agency (CFIA) and the U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS) has identified a likely source of the multistate outbreak of E. coli O157:H7 infections linked to the Topps Meat Company.

As the result of the Topps Meat Company recall investigation, FSIS had delisted Ranchers Beef, Ltd., Canadian establishment No. 630, on Oct. 20, 2007. No product from that firm has been eligible to come into the U.S. since that date.

Today, FSIS notified industry to hold all boneless beef manufacturing trim from Ranchers Beef, Ltd., Canadian establishment No. 630, or raw products produced in whole or in part from these products until the joint investigation is completed. The Agency has also today issued a notice (PDF format) to inspection program personnel in the field to retain these products.

Although products subject to recall should be returned to the point of purchase, consumers preparing other ground beef products should always follow the four Be Food Safe steps of Clean, Separate, Cook and Chill. Consumers should only eat ground beef patties that have been cooked to a safe temperature of 160 °F. The only way to be sure a ground beef patty is cooked to a high enough temperature to kill harmful bacteria is to use an accurate food thermometer.

On Oct. 23, FSIS announced new, ongoing and upcoming actions to protect public health against the risk of E. coli O157:H7, including expanded testing, including testing of imported trim at the border. On October 19, FSIS notified countries that export beef to the U.S. of new policies and programs and is working with them to ensure they implement the same or equivalent measures to protect the public from E. coli O157:H7 risks. On Oct. 4, FSIS publicly outlined the timeline of the Topps recall, the preliminary findings from its investigation of the Topps recall, actions already taken by the agency and further steps to reduce E. coli 0157:H7.