By Dr Ananya Mandal, MD. Elephantiasis is a syndrome caused by infection with a nematode parasite called the filarial worm.The parasite is transmitted form human to human via the female mosquito and grows into an adult worm that lives in the lymphatic system of a human. Lymphatic filariasis is caused by the parasites Wuchereria bancrofti, Brugia malayi, and Brugia timori, which live in the lymphatic system. 2  Another group of filarial worms including Mansonella ozzardi and Mansonella perstans occupy the serous cavity of the abdomen (serous cavity filariasis).