Elephantiasis is a disfiguring tropical disease caused by blockage of the lymphatic system in the lower limbs and in other parts of the body. The persistent blockage combined with the reaction from the skin causes severe thickening making the skin appear like that of an elephant- a pachyderm.
The microscopic Filarial parasitic worms that cause this problem can be Wuchereria bancrofti, Brugia Malayi and Brugia timori. They can all be transmitted through repeated mosquito bites - usually the anopheles type. Actually the problem is a bit more complex as there is a bacteria that lives inside the worms called Wolbachia that initiate the lymphatic overreaction. Many medics feel it is not simply a blockage but it is due to repeated skin infections that can follow once the protection of the lymphatic fluid is lost. Lymphatic drainage is essential to trap minor infections from cuts and bruises and helps us to heal fast from minor skin breaches. The absence of a good drainage system means bacteria can thrive on the skin and cause repeated infections.
The lymphatic system ( not the blood vessels) get clogged up and fail to drain resulting in massive swellings ( the same problem - but not this extent- can happen after lymph node surgery for cancers where one can get lymphoedema in the arm or legs if a particular group of lymph nodes are removed - in the groin or in the armpits)