RESUMEN
Staphylococcus aureus is one of the most prevalent bacterial pathogens causing food-borne disease worldwide. Staphylococcal food poisoning is caused by ingestion of staphylococcal enterotoxins (SEs) pre-formed in the implicated food. In this study, the incidences of S. aureus and classical SEs (SEA-SEE) contamination in 'Nham', a traditional Thai fermented pork product, were determined. Among 155 Nham samples tested, as high as 39.35% of the samples were positive for S. aureus (2-3500 MPN/g), but none were positive for the SEs. The risk factors for S. aureus contamination were highly correlated with the manufacturer and the pH of the product. A predictive model determined the probability of the presence of S. aureus to be < or = 0.24 at the pH < or = 4.6. During the fermentation process, the number of S. aureus slightly increased in the first day and decreased afterward. S. aureus counts continued to decrease when Nham was stored refrigerated. The negative result for enterotoxins and low counts of S. aureus in Nham surveyed in this study, and reduction of the pathogen counts during fermentation and storage suggested that there is very low risk of staphylococcal food poisoning from consuming properly fermented Nham.
Asunto(s)
Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Productos de la Carne/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Animales , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Enterotoxinas , Fermentación , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Humanos , Concentración de Iones de Hidrógeno , Valor Predictivo de las Pruebas , Factores de Riesgo , Intoxicación Alimentaria Estafilocócica/epidemiología , Intoxicación Alimentaria Estafilocócica/prevención & control , Porcinos , TailandiaRESUMEN
We compared rapid fingerprinting using repetitive sequence-based PCR (rep-PCR) for subtyping Campylobacter jejuni isolates to the widely used multilocus sequence typing (MLST). Representative C. jejuni isolates (n = 16) from broilers were analyzed using MLST and rep-PCR. Both techniques demonstrated an equal discriminatory power of 0.8917, and 9 subgroups were identified. Clonal identification of all 16 isolates was identical for both techniques. The rep-PCR as described in this study may be used as a rapid and cost-effective alternative for subtyping of C. jejuni isolates, or as an effective screening tool in large epidemiological studies.