Reduction of Shiga toxin-producing Escherichia coli in a beef abattoir.

The aim of this work was to reinforce actions tending to reduce Shiga toxin-producing Escherichia coli (STEC) in beef products from an Argentinean commercial abattoir implementing Hazard Analysis and Critical Control Point (HACCP) practices. An environmental stx map was built with 421 environmental samples from the slaughter, quartering, cool chamber and deboning sectors (February-May 2013). For stx determination, 125 carcass and 572 anatomical cut samples were used. Based on the environmental stx mapping results, improvement actions were designed and implemented (June and July 2013). After implementing improvement actions, 160 carcass and 477 anatomical cut samples were collected to identify stx and verify the impact of improvement actions (August-December 2013). Our results showed stx-positivity in pre-operational (10.1%) and operational (15.5%) environmental samples and in carcass and beef cut samples before (4.8 and 10.1%; p = 0.144) and after (1.2 and 4.8%; p = 0.0448) implementing improvement actions, respectively. Although improvement actions reduced stx in beef cuts, it is difficult to implement and sustain a system based on stx zero-tolerance only by reinforcing Good Manufacturing Practices, Sanitation Standard Operating Procedures and HACCP practices. The application of combined intervention strategies to reduce STEC in carcasses and beef cuts should be therefore considered.