Lymphatic Filariasis (Philariasis) is a parasitic and infectious tropical disease, that is caused by thread-like parasitic worms, of the type filarial nematode.
Examples are Wuchereria bancrofti, Brugia malayi, and Brugia timori. The parasites are transmitted by insect bites, usually mosquitoes. Lymphatic filariasis is extremely rare in Western countries.
The most spectacular symptom of lymphatic filariasis is elephantiasis—thickening of the skin and underlying tissues—which was the first disease discovered to be transmitted by a mosquito bite.
Elephantiasis is caused when the parasites lodge in the lymphatic system.
Elephantiasis affects mainly the lower extremities, whereas ears, mucus membranes, and amputation stumps are rarely affected; however, it depends on the species of filaria. W. bancrofti can affect the legs, arms, vulva, breasts, while Brugia timori rarely affects the genitals.
Filariasis is endemic in tropical regions of Asia, Africa, Central and South America with more than 120 million people infected and one billion people at risk for infection.
