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.
ABSTRACT
@#Background: The interaction of the non-deletional α+-thalassaemia mutations Haemoglobin Constant Spring and Haemoglobin Quong Sze with the Southeast Asian double α-globin gene deletion results in non-deletional Haemoglobin H disease. Accurate detection of non-deletional Haemoglobin H disease, which is associated with severe phenotypes, is necessary as these mutations have been confirmed in the Malaysian population. Methods: DNA from two families with Haemoglobin H disease was extracted from EDTAanticoagulated whole blood and subjected to molecular analysis for α-thalassaemia. A duplex polymerase chain reaction was used to detect the Southeast Asian α-globin gene deletion. Polymerase chain reaction-restriction fragment length polymorphism analysis was then carried out to determine the presence of Haemoglobin Constant Spring and Haemoglobin Quong Sze. A combine- amplification refractory mutation system protocol was optimised and implemented for the rapid and specific molecular characterisation of Haemoglobin Constant Spring and Haemoglobin Quong Sze in a single polymerase chain reaction. Results and Conclusions: The combine- amplification refractory mutation system for Haemoglobin Constant Spring and Haemoglobin Quong Sze, together with the duplex polymerase chain reaction, provides accurate pre- and postnatal diagnosis of non-deletional Haemoglobin H disease and allows detailed genotype analyses using minimal quantities of DNA.