Risk assessment of Salmonella in pork in Hanoi, Vietnam

Abstract

Quantitative Microbial Risk Assessment (QMRA) was used to assess the health risk of pork meat contaminated by Salmonella spp. in Hanoi, Vietnam. A total of 72 pork samples were collected from 4 formal markets in Long Bien District, Hanoi. Salmonella spp. was analyzed by the Most Probable Number (MPN) method. A survey consisting of self-administered structured questionnaires was conducted in 210 households to determine the consumption of pork and examine cooking and eating habits. A health risk assessment was performed for 4 scenarios of cross-contamination of Salmonella spp. including contamination from raw meat to cooked food via i) hands, ii) knife, iii) cutting board, and iv) full cross-contamination. The results showed that Salmonella spp. was detected in 25% of pork samples (18/72). The concentration of Salmonella spp. varied from 100 to 27,500 per 25 grams of pork (mean: 673 per 25 grams). Pork consumption, a component of exposure assessment, was estimated by amount and frequency. The mean amount of pork consumption was estimated at 86.1 grams per person per day; mean frequency of pork consumption was 219 days per person per year. Infection risk of Salmonella spp. was from 2.1×10-4 to 4.9×10-4 by single exposure (per consumption). The annual risk was from 4.3×10-2 to 9.5×10-2. Although this study considered only one stage of exposure in the “farm to fork” chain, the findings showed that this stage is critical and represents a potential health risk for consumers. Appropriate practices for pork meat preparation and consumption at the household level need to me targeted as risk management measures.