Filarioidea

The Filarioidea are a superfamily of highly specialised parasitic nematodes. Species within this superfamily are known as filarial worms or filariae (singular 'filaria'). Infections with parasitic filarial worms cause disease conditions generically known as filariasis. Drugs against these worms are known as filaricides. Filarioidea all are specialised parasites and the definitive host is always a vertebrate, a mammal, bird, reptile or amphibian, but not a fish. The intermediate host is always an arthropod. Most of Filarioidea parasitise wild species, birds in particular, but some, especially in the family Onchocercidae, attack mammals, including humans and some domestic animals. Conditions that result from parasitism by Onchocercidae include some of the most troublesome diseases of the warmer regions, including river blindness and elephantiasis.