ENTEROHAEMORRHAGIC ESCHERICHIA COLI ON BEEF PROCESSING SURFACES*

Abstract

Enterohaemorrhagic Escherichia coli (EHEC) is primarily an emerging foodborne bacterial pathogen. It is associated with severe complications such as haemorrhagic colitis and haemolytic uraemic syndrome in humans. Biofilm formation by EHEC on various food contact surfaces in processing plants is an important reason for cross-contamination. The present study was undertaken to know the occurrence of EHEC in beef processing surfaces, since ruminants are the reservoir host for this organism. For the study, 30 surface swabs were collected in 0.1 percent peptone water from three different cattle slaughter houses in Kerala. The selective enrichment was carried out in EC O157: H7 selective broth at 370 C for 24 h and plated on to Eosin Methylene Blue agar by incubating at 370 C for 24 h. The E. coli positive colonies were streaked on to Cefixime Tellurite- Sorbitol Mac Conkey agar and incubated at 370 C for 48 h. For further confirmation, suspected colonies were transferred on to 4- Methyl umbelliferyl beta- DGlucuronide agar plates and incubated at 37 0 C for 24 to 48 h. Positive isolates were subjected to biochemical tests. Out of the 30 samples tested for EHEC, two samples were found to be positive. This study shows that EHEC on processing surfaces can act as an important source of infection to beef consumers and it envisages thenecessity foreffectivedisinfection procedures in beef processing surfaces.

Keywords

• enterohaemorrhagic escherichia coli
• beef processing