Elephantiasis is a parasitic disease which is transmitted from human to human by mosquito bites. The parasite tends to lodge in the lymph nodes that drain the lower extremities, producing massive enlargement and deformity of the legs and genitalia. Dramatic photographs of those affected appear in every infectious diseases text.

The causative organism is Wuchereria bancrofti and the disease is also called bancrofitan filariasis and lymphatic filariasis.

Brugia malayi causes a similar disease.