Filarial worm is a microscopic, thread-like worm that causes lymphatic filariasis or elephantiasis. It is a nematode in the Filariidae family and requires an arthropod and a vertebrate host for a complete life cycle. The spread of the worm form one person to another occurs through mosquito bites. They cycle begins when an infected mosquito introduces a filarial larvae into a human host during a blood meal. In the human body, the larvae develop into an adult and reside mainly in the lymphatics. The adults produce microfilariae that have a nocturnal periodicity and are sheathed. The microfilariae move into lymph, as well as blood channels where it moves actively. During a blood meal, a mosquito takes in the microfilariae where it moves through the midgut towards the thoracic muscles. In the muscles, the microfilariae develop into the first stage larvae through to the third-stage of larvae. Once produced the third stage larvae is produced, it migrates to the proboscis through the hemocoel. This larvae can larvae can thus infect another person when bitten by an infected mosque as it feeds on the transport meal (CDC).
Most individuals infected with the filarial worms do not show symptoms of infection with others never develop any clinical symptoms. Few people, however, develop lymphedema caused by the improper functioning of the lymph system. This results in the swelling and collection of fluids. The legs are mostly affected although swelling may also take place in the arms, genitalia and breasts. Clinical manifestations may occur even after one year post infection. Other symptoms such as bacterial infections may appear causing the skin to be thick and hard (CDC). Treatment of the disease involves the use of diethylcarbamazine or DEC. The drug kills the microfilaria, as well as some of the adult worms and has been used for more than 5o years. Bacterial infections can be treated using antibiotics or prevented through proper skin hygiene (CDC).
Works Cited
CDC. Parasites - Lymphatic Filariasis. 2013. Online. 22 April 2014. <http://www.cdc.gov/parasites/lymphaticfilariasis/biology_w_bancrofti.html>.
