Fish-born parasitic zoonoses with special reference to anthropogenic impact

Abstract

Compared with other well-studied parasitic diseases, fish-borne parasitic zoonoses have been public health orphans in the world of research funding, especially because these zoonoses have been limited for the most part to populations living in low- and middle-income countries (Chai et al., 2005). Zoonotic parasites are a significant food safety problem, particularly in Asia, because fish are a very important source of protein for people living in rural areas (Thien et al., 2009). In an attempt to change the nature, so they can adjust it for their needs, humans, directly or indirectly, affect parasites occurrence. As a result of global warming it is expected for some species to become locally extirpated and experience range contractions, while introductions of others, including potentially harmful pathogens, will occur in both freshwater and marine systems (Marcogliese, 2001.). Geographical barriers are slowly being breached by international travel developing into a major industry, by improved refrigerated food transport, by growing international markets, by increased tourism and by demographic changes such as migration (Chai et al., 2005; Dorny et al., 2009). Populations at risk are expanding also as a result of changes in cultural habits and culinary practices, such as the increase of eating raw, marinated, smoked, salted, pickled, airdried or undercooked fish meat and fish products. Eating sushi, sashimi, koi-pla, kinilaw and cevishe is becoming inceasingly fashionable in many countries (Macpherson, 2005). In the last decade it has been noted increasing in the number of people eating meals prepared in restaurants, canteens and fast food outlets as well as from street food vendors who do not always respect food safety (Dorny et al., 2009). All of these has led to a dramatic rise in the incidence of a large number of fish-borne zoonotic parasitic infections in previously uninfected ethnic groups (Macpherson, 2005). The role of some factors like ages, malnutrition, HIV infection and other underlying medical conditions should not be neglected in etiopathogenesis of fish-borne parasitic zoonoses (Dorny et al., 2009).