|Koohmaraie, Mohammad - FORMER ARS EMPLOYEE|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 26, 2009
Publication Date: May 13, 2009
Citation: Bosilevac, J.M., Koohmaraie, M. 2009. Non-O157 Shiga toxin Producing Escherichia coli in United States Beef Production [abstract]. 7th International Symposium on Shiga Toxin (Verocytotoxin)-Producing Escherichia coli Infections (VTEC2009) Paper No. P03.2.2. p 71. Interpretive Summary: No interpretive summary is required.
Technical Abstract: Escherichia coli O157:H7 is classified as an adulterant in U.S. beef. Its presence is rigorously monitored. However, numerous non-O157 STEC have been associated with disease. The six most common non-O157 STEC associated with disease in the U.S. have been identified by the CDC as O26, O45, O103, O111, O121, and O145. Non-O157 STEC have become a concern of the beef industry and regulatory officials, but little data exists for STEC prevalence in ground beef or the primary source of beef that is to be ground. In the U.S. cull dairy and beef breeding cows and bulls are harvested and used almost entirely in the production of ground beef. This study reports the prevalence of STEC on final carcasses (n = 3,040) at slaughter plants that harvest cull cows and bulls, and reports the prevalence of STEC in commercial ground beef (n = 4,499) supplied by multiple commercial grinders. The prevalence of STEC on final carcasses as measured by PCR for stx1 and stx2 genes was found to be 3%. Forty-eight percent of these were confirmed by culture isolation of a STEC. The prevalence of stx1 and stx2 genes in ground beef was 26%. Recovery of STEC isolates from ground beef was lower than from carcasses. Thirty percent of stx positive ground beef samples were confirmed to have STEC present by culture isolation. The most commonly observed STEC was serotype O113. STEC that carried the intimin gene were infrequent (13% of carcass isolates and 2% of ground beef isolates) and when found were serotypes O103 and O121. Other common serotypes, O26, O45, O111, and O145 were not isolated from any beef sources.