Filariasis is a filarial infection caused by parasitic nematodes (roundworms) spread by different vectors. They are included in the list of neglected tropical diseases.
The most common type is lymphatic filariasis caused by three species of Filaria that are spread by mosquitoes. Other types of filariasis are onchocerciasis also known as river blindness caused by Onchocerca volvulus; Loa loa filariasis (Loiasis) caused by Loa loa; Mansonelliasis caused by three species of Mansonella, and Dirofilariasis caused by two types of Dirofilaria. All of these worms belong to the superfamily Filarioidea.