Quantitative risk assessment of Listeria monocytogenes in retail pork of Hubei Province

ObjectiveTo predict the risk of population morbidity by evaluating the contamination level of Listeria monocytogenes in commercially available fresh pork from the retail to the consumption stage and combining it with its cross-contamination of ready-to-eat food.MethodsBased on the monitoring results in Hubei Province to determine the contamination level of Listeria monocytogenes in pork， a growth prediction model and a cross-contamination model were applied， and a Monte Carlo method was used for simulation and analysis to estimate the level of contamination of ready-to-eat foods by pork in the kitchen and to project the population health risk in combination with a dose-response model.ResultsThe amount of Listeria monocytogenes transferred to ready-to-eat food by cross-contamination was 1.30 and 1.90 CFU for chilled and hot pork， respectively， which resulted in obtaining an annual probability of morbidity of 2.52×10-9-7.62×10-9 for susceptible population and 2.61×10-11-6.86×10-11 for non-susceptible population. The results of the sensitivity analyses showed that the treatment of of raw pork followed by preparation of ready-to-eat food， daily pork consumption， and initial contamination level of pork were the main factors affecting the risk of morbidity.ConclusionThe probability of Listeria monocytogenes in commercially available pork in Hubei Province causing morbidity in residents is low. To further reduce the health risk to residents， it is recommended to reduce the contamination level of Listeria monocytogenes in pork at source and to guide residents to regulate household kitchen operation and cooking consumption habits， and reduce the cross-contamination in pork handling.