Molecular characterization of Escherichia coli O157:H7 recovered from meat and meat products relevant to human health in Riyadh, Saudi Arabia

Saudi J Biol Sci. 2015 Nov;22(6):725-9. doi: 10.1016/j.sjbs.2015.06.009. Epub 2015 Jun 17.

Abstract

Raw meat can harbor pathogenic bacteria, potentially harmful to humans such as Escherichia coli O157:H7 causing diarrhea and hemolytic-uremic syndrome (HS). Therefore, the current study was carried out to evaluate the prevalence and the molecular detection characterization of E. coli serotype O157:H7 recovered from raw meat and meat products collected from Saudi Arabia. During the period of 25th January 2013 to 25th March 2014, 370 meat samples were collected from abattoirs and markets located in Riyadh, Saudi Arabia "200 raw meat samples and 170 meat products". Bacteriological analysis of the meat samples and serotyping of the isolated E. coli revealed the isolation of 11 (2.97%) strains of E. coli O157:H7. Isolation of E. coli O157:H7 in raw beef, chicken and mutton were 2%, 2.5%, and 2.5%, respectively, however, there was no occurrence in raw turkey. The incidences of E. coli O157:H7 in ground beef, beef burgers, beef sausage, ground chicken and chicken burgers were 5%, 10%, 0.0%, 5% and 0.0%, respectively. The multiplex PCR assay revealed that 3 (27.27%) out of 11 E. coli O157:H7 isolates from raw beef, chicken and mutton had stx1, stx2, and eae while 5 (45.45%) E. coli O157:H7 isolates from ground beef, ground chicken, and raw beef had both stx1 and stx2. However, from beef burgers, only one E. coli O157:H7 isolate had stx1 while two were positive for hlyA gene. These results call for urgent attention toward appropriate controls and good hygienic practices in dealing with raw meat.

Keywords: E. coli O157:H7; Hemolysin; Intimin gene; Meat; Multiplex PCR; Shiga toxin.