Fish substitutions which may increase human health risks from zoonotic seafood borne parasites: A review

Abstract

In recent times, broad scale fish substitution has been identified globally. Life threatening or serious human health concerns identified in published literature associated with this type of food fraud are consumption of toxins, highly allergenic species, or contaminates which may be present in substituted fish. However, zoonotic parasites as a risk to human health in substituted fish has not been considered. This review aimed to aggregate cases of fish substitution described in published literature and discuss descriptively the potential of substituted fish to be a greater zoonotic parasite human health risk than fish in the labelled product. A literature search was conducted for cases of fish substitution from 2000 to May 2019. In 55 publications, 9450 samples of “Sold as” fish were identified substituted with a different fish species. Descriptive discussion of human health threats posed by fish-borne zoonotic parasites considered fish preparation/parasite fauna of “Sold as” compared to “Identified as” species. Fish pairings which may be a human health risk (“Sold as”: “Identified as”: zoonotic parasite) were, Sablefish: Patagonian toothfish (N = 7704)/Antarctic toothfish (N = 154): Anisakis simplex; Generic halibut: Generic flounder (N = 38) and Olive flounder (N = 15) respectively: Kudoa spp.; seven saltwater fish species: Striped catfish (N = 16): zoonotic trematodes; seven and two salt water species: Nile tilapia (N = 25) and Generic tilapia (N = 20), respectively: Gnathostoma spp. zoonotic trematodes, Cryptosporidium parvum and Dibothriocephalus latus (syn. Diphyllobothrium latum). Fish substitution was identified in commercial sectors (sector: mislabelled sample number), online vendors: 7854; Retail: 411; Restaurants: 316; Wholesale: 92; Market/restaurant/grocery: 69; Grocery: 68; Sushi restaurants: 68 and Retail/sushi bars/non-sushi restaurants: 67. In conclusion, review of the literature showed varying amounts of fish substitution in all publications. Substituted fish included species vulnerable to infection with a zoonotic parasite not commonly found in the fish which it substituted for. Zoonotic fish borne parasites in substituted fish may pose a human health risk and testing for fish authenticity may be advisable. In addition, medical professionals should be made aware, in cases of fish borne human illness where parasitism is considered, clinical presentation may not match the parasite profile of the fish the consumer is believed to have consumed.