Waterborne Parasitic Diseases in Ocean

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Book Chapter

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Coastal Sciences, Gulf Coast Research Laboratory


Ocean Science and Engineering


Several parasites or those in the marine environment as posing no public health risk. Over the last few decades, more and more parasites in different groups have been determined to be zoonotic agents that either are known to infect humans or can serve as a potential public health risk based on experimental infections in nonhuman mammalian hosts or are closely related to known human-infecting agents. These parasites include metazoans and “protozoans” that occur in water or in seafood products. Protozoa occurs in quotation marks because its historic higher taxonomic groups are not necessarily closely related [3] and some include stages with more than one cell. For example, a single myxosporidian spore may develop from a stage consisting of 13 cells, and molecular data demonstrate no relationship between Myxosporea from commercial and subsistence vessels results in increased infections in fishes and marine mammals that feed on the wastes. Alternatively, regulations in some countries are lacking in regard to fishery products or for imported fishery products but not necessarily all meats, leaving consumers with the false impression that the products are safe. (6) Climatic and environmental health conditions are always changing, and, with those changes, infection dynamics of parasites quickly change. For example, during the El Niño of 1997–1998, the junction of the warmwater Kuroshio Current from the south with the cool Oyashio Current from the north moved 3,000 km northward from Kyushu to Hokkaido, Japan. This migration of the current’s junction and its temperature elevation of 3.4°C caused an increase in abundance of krill, the intermediate host of Pseudoterranova azarasi and members of the Anisakis simplex complex. The sea lion final host of P. azarasi occurred in Hokkaido but not Kyushu, and, in addition, protected cetaceans that are the final hosts of A. simplex sensu lato migrated north so as to feed heavily on krill or on fish that ate the krill, acquiring the juvenile nematodes from them. Consequently, the Japanese used to eating nearly parasite-free seafood

Publication Title

Infectious Diseases

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