This disease rarely has symptoms but can cause a large amount of swelling in the arms, legs and even genitals. The Wuchereria Bancrofti is a human parasitic roundworm that is a major cause of lymphatic filariasis also known as elephantiasis. People suffering from this disease say that the growth is so painful and the accompanying physical changes can really affect the person socially and financially. These filarial worms are spread by mosquito vector. The Bancrofti is the most common and affects over 120 million people, primarily in Central Africa and the Nile delta, South and Central America and the tropical regions of Asia. Only limited treatments exist but as of today, no vaccines have been developed.