Filariasis is a parasitic disease caused by filariasis parasitizing lymphatic tissue, subcutaneous tissue or serous cavity. The disease is transmitted by blood-sucking insects. The signs and symptoms of filariasis vary according to the location of filariasis. The early stage is mainly lymphangitis and lymphadenitis, and the late stage is a series of symptoms and signs caused by lymphatic obstruction. Diagnosis is mainly based on the detection of microfilaria in blood or skin tissue.