Quantitative Risk Assessment Of Salmonella In Poultry In Shandong Province

[Background]Salmonella is one of the most common food borne pathogens. It broadly exists in nature and always leads to infectious diarrhea by eating contaminated food. The infection caused by salmonella happened around a year but mainly in summer and autumn. There’re fever, diarrhea, abdominal pain, vomiting, nausea and other clinic symptoms of gastroenteritis. Chicken meat is salmonella’s common host, so eating the contaminated chicken is the chief cause of infection. The risk surveillance and risk assessment of salmonella in poultry in Shandong Province can help risk managers to provide scientific and effective measures for controlling salmonella. [Objectives]To investigate the contamination rate, contamination concentration and serotype distribution of salmonella in the whole process of broiler cultivation, slaughtering and retail of Shandong Province in 2012, to collect data for quantitative risk assessment of salmonella.To construct a quantitative risk assessment model of salmonella on carcass in poultry slaughterhouse, to find out effective interventions to reduce salmonella contamination by sensitive analysis, and to provide scientific basis about controlling salmonella measure for risk managers.To estimate the risk of human salmonellosis due to consumption of poultry in Shandong Province, and to find out the major influencing risk factors by sensitive analysis. [Methods]We collected 1197 samples from the chicken breeding farm, slaughterhouse, large supermarkets and farmer’market in Jinan and Zibo City of Shandong Province in 2012 and did the qualitative, quantitative and serotype test for salmonella according to GB 4789.4-2010.We constructed a modular process risk model(MPRM) from evisceration to chilling in Excel Sheet using the data of the process parameters in poultry and the salmonella concentration surveillance of Shandong Province in 2012.The MPRM was simulated by @risk software.We analyzed the salmonella concentration surveillance data on poultry of Shandong in 2012 and constructed a modular process risk model(MPRM) simulating the level of salmonella throughout the retail-to-table pathway. Combining the poultry consumption and population data of Shandong Province, the risk characterization was analyzed by the dose-response β-Poisson model developed by WHO/FAO.[Results]The salmonella positive rate of the fecal in breeding farm was 26.7%, the chicken before slaughter was 16.5%, the poultry carcass after defeathering was 42.9%, the poultry carcass after chilling was 35.9%, the water sample in chilling pool was 24.1%, the chicken meat in retail was 35%.There were 375 positives sample, the Indiana and Enteritidis Salmonella accounted for 44.3% and 34.1% respectively. There were 331 quantitative test result.20.2% of the quantitative data were less than 0.3 MPN,56.2%,16.9% and 6.6% accounted for 0.3-10 MPN,10-110MPN and more than 110MPN respectively.The concentration of salmonella on carcass after chilling was 8.08MPN/g which was calculated by model. The sensitive analysis indicated that the correlation coefficient of the concentration of salmonella after defeathering and in chilling pool were 0.89 and 0.26,which were the primary factors to the concentration of salmonella on carcass after chilling.The assessment result indicated that the risk probability of salmonellosis by consumption of poultry in Shandong province is 2.2×10-4, the number of illness per 10,000 in a year is 137. The sensitive analysis showed that the correlation coefficient of the salmonella concentration from retail and the cross-contamination in kitchen were 0.96 and 0.26. [Conclusions]The salmonella contamination was serious through the broiler chain. The salmonella positive rate on carcass after deathering, after chilling and in retail were the top three. The serotype test indicated that Indiana and Enteritidis Salmonella were the primary serotype in Shandong Province. The quantitative result showed that the salmonella contamination was mostly low concentration.The study provided a quantitative assessment model structure for salmonella on carcass in poultry slaughterhouse. The risk manager could control the contamination of salmonella on carcass after chilling by reducing the concentration of salmonella after defeathering and in chilling pool.The predicting risk is a little high, we could reduce the risk by strengthening the supervision in retail and advising consumer correct cooking and cutting in kitchen.