The U.S. Department of Agriculture Food Safety and Inspection Service said Public Health Alert it "has reason to believe, based on information provided by the Canadian Food Inspection Agency, beef from cattle slaughtered during the period associated with the recall was produced under insanitary conditions that resulted in a high event period -- a period when the trim from carcasses exhibited an unusually high frequency of positive findings for the possible presence of E. coli O157:H7."
The alert said products produced Aug. 24, 27, 28, 29 and Sept. 5 "are considered adulterated and must be either destroyed or verified as having received a full lethality treatment."
The FSIS said all receivers of affected beef from the Canadian-initiated recall have been notified and have removed product from commerce, and will take appropriate action if prohibited activity is found.
The U.S. government tested raw boneless beef trim product from Canadian Establishment 038, XL Foods, Inc., confirmed positive for E. coli O157:H7 on Sept. 3, the U.S. and Canadian agencies began an investigation and CFIA announced a recall by XL Foods, Inc. of a variety of ground beef products on Sept. 16.
FSIS also issued a Public Health Alert on Sept. 20 provided updated information.