Filariasis control. Potential breeding site for mosquitoes that transmit lymphatic filariasis. The tyres must be emptied of the water in which the mosquito larvae develop, and then covered against the rain or buried underground. Larger areas of water must be sprayed with insecticide. Lymphatic filariasis is a disease caused by parasitic worms transmitted by mosquitoes. The worms cause the body's lymph vessels to become blocked. Lymph fluid then accumulates in the surrounding tissues (oedema). Repeated infection may result in elephantiasis as the affected part of the body, commonly a limb, becomes massively enlarged. Photographed in Samoa in 1999.