FilariasisFilariasis is a chronic infection caused by filarid worms. Around 10 species of Filaridae family are parasitic to man. Adult worms live in the tissues or body cavities of the vertebrate hosts. The female filarid worms produce embryonated eggs, which during oviposition contain embryos that become delicate thread like organisms called microfilariae. The microfilarae are circulated in the peripheral blood or other cutaneous tissue from where they are transmitted by blood sucking arthropods. The disease is widely prevalent in Asian countries including India.The lymph glands of patients get enlarged. Adenolymphangitis often accompanied by swelling of a limb, recurrent fever, eosinophilia and pulmonitis. Sterile abscess appears at varying intervals. Diagnosis is made on the basis of clinical symptoms and demonstration of microfilariae in thick blood smears. The disease can be prevented by reducing the vector population and environmental sanitation.