PREVALENCE AND ANTIMICROBIAL RESISTANCE PROFILES OF SALMONELLA SEROTYPES, CAMPYLOBACTER AND YERSINIA SPP. ISOLATED FROM RETAIL CHICKEN AND BEEF, TEHRAN, IRAN

Prevalence and antimicrobial resistance profiles of Salmonella serotypes, Campylobacter and Yersinia spp. isolates from fresh chicken and beef meat obtained at retail outlets in Tehran, Iran, were determined. A total of 379 samples (190 chicken and 189 beef) were collected between April 2006 and April 2007 and analyzed for these foodborne pathogens, and isolates were subjected to antimicrobial resistance testing. Salmonella, Campylobacter and Yersinia were isolated from 124 (33%), 109 (29%) and 60 (16%) of the samples, respectively. S. Thompson was the dominant serovar of Salmonella, isolated from 75% to 58% of the Salmonella-positive chicken and beef samples, respectively, with S. Hadar a distant second. Of Campylobacter isolates, 71% were resistant to nalidixic acid and 47% to ciprofloxacin, with 37 (40%) multidrug resistant. A high percentage of Salmonella isolates were resistant to antibiotics, including 82% nalidixic acid, 69% tetracycline, 63% trimethoprim and 52% streptomycin. Eighty-five (68.5%) isolates were multidrug resistant. The most Yersinia spp. were resistant to cephalotin 59 (98%) and ampicillin 31 (52%), with 14 (23%) multidrug resistant. Such baseline information on the prevalence and antimicrobial resistance of foodborne pathogens on raw foods of animal origin is needed to not only determine the extent of the problem but also to serve as a point of reference for monitoring changes that occur over time. Such data are essential for use in developing effective risk management strategies.