Lymphatic filariasis (LF), commonly known as elephantiasis is a disfiguring, disabling disease, usually acquired in childhood. The adult produces millions of very small, immature larvae known as microfilariae, which circulate in the peripheral blood with marked nocturnal periodicity. The worms usually live and produce microfilariae for 4-6 years.
Lymphatic filariasis is transmitted through mosquito bites. The microfilariae enter the body of a mosquito when it feeds on the blood of a person carrying microfilariae in their blood (mf carriers). It takes 7-21 days for the microfilariae to develop inside the body of the mosquito.
Many mosquito bites over several months to years are needed to get lymphatic filariasis. People living for a long time in filaria endemic areas where the disease is common are at the greatest risk for infection. The infection can be detected by night blood survey.
At first, most people usually do not feel any symptoms until after the adult worms die. The disease usually is not life threatening, but it can permanently damage the lymph system and kidneys. Because the lymph system does not work right, fluid collects and causes swelling in the arms, breasts and legs. The name for this swelling is lymphoedema. For men, the genital area also becomes swollen, a condition known as hydrocele. Also, the swelling and the decreased function of the lymph system make it difficult for the body to fight germs and infections. These people will have more bacterial infections in the skin and lymph system. This causes hardening and thickening of the skin, which is called elephantiasis.
Prevention includes giving entire communities medicine that kills the microscopic worms and controlling mosquitoes. Avoiding mosquito bites is another form of prevention. The mosquitoes that transmit the filarial worms usually bite between the hours of dusk and dawn. If you live in an area with lymphatic filariasis take the following precaution:
People infected with adult worms can take a yearly dose of medicine (DEC) that kills the circulating microfilariae in the blood. While this does not kill all the adult worms, it does prevent infected people from giving the disease to someone else. Even after the adult worms die, lymphoedema can develop. To prevent lymphoedema from getting worse by following several basic principles: