Parasitic helminthes are worms of great medical and veterinary importance. They include the Nematodes (Roundworms) and the Platyhelminthes (Flatworms) which consist of the Trematodes (Flukes) and Cestodes (Tapeworms). These invertebrates are agents of debilitating, deforming and fatal diseases of humans and their agricultural animals and so responsible for great morbidity and mortality. Domestic and wild animals affected by a barrage of helminthes infections may also transmit these infections to humans by zoonoses [1, 2]. Helminthes infections may be vectored, food or water borne. Infections due to parasitic helminthes are no doubt widespread in tropical as well as temperate regions with both regions having their own share of peculiar and distinctive infections. In fact, in Tropical Africa, helminthiasis is regarded as part of the “Neglected tropical diseases” [1]. The platyhelminthes (flatworms) are acoelomates that possess the beginning of some advanced features of the animal kingdom such as cephalization, bilateral symmetry and triploblastic body organization. The trematodes or flukes are endoparasitic platyhelminthes with complex life cycles. The Digeneans are a peculiar group of trematodes in having mollusca (snails) as their intermediate hosts in a life cycle involving one or two hosts; for example: Schistosoma haematobium and Schistosoma mansoni (blood flukes of man), Fasciola hepatica and Fasciola gigantica (sheep and cattle liver flukes) and Paragonimus westermani (human lung fluke). Cestodes differ in a number of ways from other flatworms. Their bodies are elongated, ribbon-like and flattened, made up of many segments called proglottids. Most cestodes require at least two hosts of which vertebrates are usually the intermediate host [2]. All these features are adaptations to their exclusively parasitic mode of existence; for example, Taenia solium and Taenia saginata (pork and beef tapeworms of man), Echinococcus granulosus and Echinococcus multilocularis (dog tapeworms) and Diphyllobothrium latum (broad fish tapeworm of man).
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