Parasite detection in food:Current status and future needs for validation

Background Many parasites (protozoa and helminths) can be transmitted through food and lead to infections with high morbidity, as well as disease outbreaks. Although the importance of foodborne parasites (FBP) is recognised by many sectors of the food industry, standardized analytical methods and validation procedures for testing food for FBP are lacking. Scope and approach:Current methods for detection of FBP, and their validation, are critically reviewed, focusing on priority FBP in Europe: the helminths Echinococcus multilocularis, Echinococcus granulosus, Taenia saginata, Trichinella spp., and Anisakidae, and the protozoa Toxoplasma gondii, Cryptosporidium spp., and Giardia duodenalis. Key findings and conclusions:Standard methods exist for detection of T. saginata in beef, and Trichinella spp. in meat (and are mandatory at meat inspection in Europe), Anisakidae in fish, and Cryptosporidium spp. and G. duodenalis in leafy green vegetables and berry fruits. For other FBP or foods, methods used in sample surveys have been described, but validation data are generally absent; limits of detection are not provided, ring trials have rarely been performed, and for most FBP quality control materials, proficiency schemes, and reference standards are lacking. The use of surrogate particles or organisms for method development or validation purposes needs to be carefully considered. Documented procedures for validation, such as ISO17468 and ISO16140-2:2016 that were established for bacteria, are mostly inappropriate for FBP. The development and application of standardized and validated detection methods would enhance understanding of the foodborne route of transmission, improve risk assessments, and help identify and verify critical control points.Peer Reviewe

Visible parasites in fresh cephalopods sold on the Italian market: impact on consumers’ perception on safety and quality

Background: Visible parasites in seafood may represent a hazard, in the case of zoonotic species, and a defect, in the case of obvious contamination, making products unsafe and unfit for human consumption. Objective: to evaluate the presence of visible parasites in fresh cephalopod products sold in Italy Materials and Methods: data on the species most commonly commercialized as fresh in Italy were collected. Based on literature data Doryteuthis pealeii (Atlantic squid) and Eledone spp., comprising E. cirrhosa and E. moschata (horned octopus and musky octopus, respectively) were selected, considering that these commercial species had been rarely investigated. 55 Eledone spp. caught in the Mediterranean Sea (FAO area 37) and 54 D. pealeii from the Northwest Atlantic (FAO area 21) were examined by visual inspection and artificial digestion (viscera and mantle separately). Parasites were morphologically identified, counted and molecularly analysed. Prevalence (P) and mean abundance (MA) were calculated. Results: 7 specimens of D. pealei (P: 12.7% ±8.8 95%CI; MA: 0.2) were positive for plerocercoid larvae of Clistobothrium sp. (n=11) which were found in the viscera; in 2 other specimens 2 nematodes identified as Anisakis simplex were found in the viscera and in the mantle. In Eledone spp. 6 nematodes not belonging to Anisakis spp., for which morphological and molecular identification is ongoing, were found in the mantle of 4 specimens (P: 7.3% ±6.87 95%CI; MA: 0.1). Discussion and Conclusion: outcomes from this study show the possible presence, also in the mantle, of visible zoonotic parasites (A. simplex). In addition, the presence of large (1.5-2 cm), mobile plerocercoid larvae was detected. Such findings influence products’ safety and quality, as well as consumers’ related perception. Perspectives: the study will provide data for better implementing Food Business Operators inspection procedures aimed at guaranteeing products’ quality and consumers’ safety

Molecular Characterization of Clistobothrium sp. Viable Plerocercoids in Fresh Longfin Inshore Squid (Doryteuthis pealeii) and Implications for Cephalopod Inspection

Cephalopods, an appreciated seafood product, are common hosts of marine cestodes. The aim of this work is to report visible alive plerocercoids in longfin inshore squid (Doryteuthis pealeii), a cephalopod species commercialized as fresh and whole in Italy. Seventy D. pealeii from the Northwest Atlantic (FAO area 21) were collected and visually inspected. In total, 18 plerocercoid larvae were found in the viscera of 10 host specimens (P: 14.3% 95% CI 7.1–24.7; MI: 1.8, MA: 0.26; range 1–4) and molecularly analyzed targeting the variable D2 region of the large subunit (LSU) rRNA gene and the cytochrome c oxidase subunit I (COI) gene. The molecular characterization allowed to identify all the plerocercoids as Clistobothrium sp., a cestode of the Phyllobothriidae family with Lamnidae sharks as definitive hosts, and cephalopods as second intermediate hosts. These findings represent the first molecular record of Clistobothrium sp. in D. pealeii, thus contributing to elucidate its poorly known life cycle. Even if not affecting consumer’s health, these visible parasites may represent a reason for disgust for consumers. Therefore, the results suggest that Food Business Operators should also check for the presence of these visible parasites during inspection and underline the importance of a correct consumers’ education

Parasite detection in food: Current status and future needs for validation

Background: Many parasites (protozoa and helminths) can be transmitted through food and lead to infections with high morbidity, as well as disease outbreaks. Although the importance of foodborne parasites (FBP) is recognised by many sectors of the food industry, standardized analytical methods and validation procedures for testing food for FBP are lacking. Scope and approach:Current methods for detection of FBP, and their validation, are critically reviewed, focusing on priority FBP in Europe: the helminths Echinococcus multilocularis, Echinococcus granulosus, Taenia saginata, Trichinella spp., and Anisakidae, and the protozoa Toxoplasma gondii, Cryptosporidium spp., and Giardia duodenalis. Key findings and conclusions:Standard methods exist for detection of T. saginata in beef, and Trichinella spp. In meat (and are mandatory at meat inspection in Europe), Anisakidae in fish, and Cryptosporidium spp. and G. duodenalis in leafy green vegetables and berry fruits. For other FBP or foods, methods used in sample surveys have been described, but validation data are generally absent; limits of detection are not provided, ring trials have rarely been performed, and for most FBP quality control materials, proficiency schemes, and reference standards are lacking. The use of surrogate particles or organisms for method development or validation purposes needs to be carefully considered. Documented procedures for validation, such as ISO17468 and ISO16140-2:2016 that were established for bacteria, are mostly inappropriate for FBP. The development and application of standardized and validated detection methods would enhance understanding of the foodborne route of transmission, improve risk assessments, and help identify and verify critical control points