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Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii are protozoan parasites that have been highlighted as emerging foodborne pathogens by the Food and Agriculture Organization of the United Nations and the World Health Organization. According to the European Food Safety Authority, 4786 foodborne and waterborne outbreaks were reported in Europe in 2016, of which 0.4% were attributed to parasites including Cryptosporidium, Giardia and Trichinella. Until 2016, no standardized methods were available to detect Giardia, Cryptosporidium and Toxoplasma (oo)cysts in food. Therefore, no regulation exists regarding these biohazards. Nevertheless, considering their low infective dose, ingestion of foodstuffs contaminated by low quantities of these three parasites can lead to human infection. To evaluate the risk of protozoan parasites in food, efforts must be made towards exposure assessment to estimate the contamination along the food chain, from raw products to consumers. This requires determining: (i) the occurrence of infective protozoan (oo)cysts in foods, and (ii) the efficacy of control measures to eliminate this contamination. In order to conduct such assessments, methods for identification of viable (i.e. live) and infective parasites are required. This review describes the methods currently available to evaluate infectivity and viability of G. duodenalis cysts, Cryptosporidium spp. and T. gondii oocysts, and their potential for application in exposure assessment to determine the presence of the infective protozoa and/or to characterize the efficacy of control measures. Advantages and limits of each method are highlighted and an analytical strategy is proposed to assess exposure to these protozoa.

Among 24 foodborne parasites ranked by FAO/WHO, 15 are associated with food of non-animal origin (FoNAO). Control of these hazards is essential for food safety. Control measures to inactivate parasites in FoNAO are reviewed. Preventing contamination is key to ensuring the safety of fresh produce. However, additional control measures can further reduce the likelihood of occurrence of infectious parasites in FoNAO. Key Findings and Conclusions: The efficacy of treatments depends on parasite species, developmental stage, matrix, and application conditions. Conventional pasteurization (72 °C; 15 s) inactivates parasites in most matrices, although some parasites are more heat resistant, and this may be an inappropriate method for many FoNAO that are intended for eating fresh and raw. Freezing at −20 °C for 2 days inactivates most, but not all, parasites, and some are highly resistant to freezing. Parasites generally survive chemical disinfection, making its application at effective doses often unsuitable at an industrial scale. Ozone and chlorine dioxide are the most promising in terms of efficacy and dosage, nevertheless challenges remain in their application especially for the most fragile produce. High-pressure processing is an efficient technology, providing good inactivation of parasites. Further research should focus on standardizing experimental approaches for evaluation of inactivation techniques and development of methods to measure parasite inactivation in food matrices. • Various parasites can be transmitted to people via foods of non-animal origin (FoNAO). • Potential methods for inactivation of transmission stages in FoNAO are reviewed. • Thermal methods may not be appropriate for FoNAO; some parasites survive freezing. • Chemical methods have mostly been characterised in simple matrices rather than food. • Standardised evaluation methods are lacking, making comparisons difficult. [ABSTRACT FROM AUTHOR]