Additionally, fish tapeworms are responsible for classic zoonotic diseases such as diplogonoporiasis (Kino et al, 2002) and diphyllobothriasis, also known as 'tapeworm pernicious anemia'. The latter is due to vitamin B12 deficiency, a condition that encompasses megaloblastic, macrocytic anemia with thrombocytopenia and leukopenia. This deficiency is a result of a high demand for vitamin B12 in the ATPgenerating pathways in Diphyllobothrium latum and D. dendriticum, a feature common to many tapeworm species (Arme et ai., 1983; Schantz, 1996; Dick et al, 2001). It has also been shown that some larval tapeworms have the potential to induce anaphylactic reactions in animals that are fed fish meat infected with these larvae, and a possibility for the development of similar hypersensitivity in humans has been suggested (Vazquez-Lopez et al, 2001, 2002).