Strain variability is one of the most important factors to influence the accuracy of foodborne pathogens risk assessment, such as Listeria monocytogenes, Salmonella spp. Strain-to-strain variation is defined as the inherent differences among identically treated strains of the same microbial species. The differences cannot be eliminated by changing test methods or improving test protocols. This review addresses presently related studies of strain variability. Based on the effect of strain variability on the outcome of risk assessment, we summarize sources of variabilities in food chain, strain phenotypic variabilities and the methods to integrate strain variability in growth and inactivation into predictive modelling, and indicate the inadequacies in the study of strain variability. We suggest further study the mechanism of strain variability, expand the comparison of variability among different sources, and integrate the variability of gene expression, protein and cell metabolism into the predictive modelling.
菌株变异性是影响食源性致病菌风险评估结果准确性的一个重要因素，它普遍存在于单核细胞增生李斯特氏菌、沙门氏菌等各种食源性致病菌中。菌株变异性是菌株之间的固有差异，不能通过改变试验方法或改善试验方案消除。本文针对近年来菌株变异性的研究内容，基于菌株变异性对风险评估结果的影响，从食品链中变异性的来源、食源性致病菌表型变异性以及整合菌株生长、失活变异性到预测微生物模型中的方法三个方面进行综述，并指出目前菌株变异性研究中的不足，提出深入研究菌株变异性机制，扩展不同来源变异性的比较，进一步整合基因表达、蛋白质和细胞代谢等菌株变异性于预测模型中的建议。.
Keywords: foodborne pathogens; risk assessment; strain variability.