Elephantiasis, or filariasis, is caused by

1. Filariasis is a chronic disease of the lymphatic vessels. 2. Wuchereria is the filarial worm responsible. 3. Ascaris, the common round worm, causes intestinal infection instead. 4. Gross deformity of the lower limbs follows long standing lymphatic obstruction. _Source: syllabus Biology Ch7 'Human Health and Disease', section 7.1_