ABSTRACT
Abstract. Staphylococcus aureus food poisoning and Salmonellosis outbreaks have been associated with two popular ready-to-eat items: sushi and sashimi. Thus this study aims to determine the prevalence of S. aureus and S. enterica in sushi and sashimi in Malaysia. Sushi (149) and sashimi (51) were collected from 14 retail outlets comprising supermarkets, hypermarkets, restaurants and open-air night markets. Bacterial isolation was carried out using Baird-Parker and CHROMagar Salmonella Plus selective media. The food pathogens isolated from microbiological media were then confirmed by molecular analysis. The results confirmed an overall S. aureus and S. enterica contamination of 42% (84/200) in the sushi and sashimi samples. Regarding prevalence of the individual pathogens involved, S. aureus was detected in 26% (52/200) and S. enterica in 16% (32/200) of the contaminated samples. This study demonstrates a high occurrence rate of S. aureus and S. enterica in sushi and sashimi foods in Malaysia, and warrants the necessity to monitor the microbiological process of RTE foods to ensure food safety for consumers.
ABSTRACT
Salmonella enterica is one of the leading causes of human foodborne infections. The objectives of this study are to investigate S. enterica prevalence in sushi and sashimi in Malaysia, to determine the presence of virulence genes and the antimicrobial resistance profiles of isolated S. enterica. In the 200 samples tested, 16% were positive for S. enterica. Sixty-six percent of the S. enterica isolates harboured at least one virulence gene and the most common virulence gene was sifA (37.5%). Antibiotic susceptibility testing showed 65.6% (21/32) of the isolates to be resistant to at least one antibiotic tested, with sulfamethoxazole resistance as the most common (50%). Resistance to the drugs-of-choice (fluoroquinolones and third-generation cephalosporin) for severe salmonellosis were also detected – ceftriaxone (25%), ceftazidime (28.1%) and ciprofloxacin (9.4%). Two isolates (9.5%) were resistant to all antibiotic tested while 12 isolates (37.5%) exhibited multi-drug resistance (MDR) with 10 different MDR profiles. Most of the isolates presented MDR profilesAP, AUG, FOX, NA (penicillins, beta-lactams, cephems and quinolone) with or without the addition of other drugs. In conclusion, the high rate of S. enterica prevalence in the sampled sushi and sashimi warrants increased safety measures for sushi and sashimi preparation.