There are three types of filariasis caused by nematode infections.
Filariasis is a tropical infectious disease caused by nematode parasites. There are about eight known filarial parasites, which use human as a host in their life cycle. Filariasis can be divided into three categories according to the part of the body in which the filarial worms occupy.
Lymphatic filariasis can be causes by three worms Wuchereria bancrofti, Brugia timori and Brugia malayi. In lymphatic filariasis the nematodes occupy the lymphatic system, including the lymph nodes. Chronic cases of lymphatic filariasis are known as Elephantiasis.
Tropical elephantiasis shows symptoms line night cough, breathing problem, fever, weight loss, etc. These symptoms are due to the allergies created by the larval forms of the parasites.
The parasite occupies the fat layer below the skin in subcutaneous filariasis and is caused by the African eye worm (Mansonella streptocerca, Onchocerca volvulus) and the Guinea worm (Dracunculus medinensis).
When the parasites (Mansonella perstans and Mansonella ozzardi) occupy the serous cavity of the abdomen, it leads to the serous cavity filariasis. In all the three cases the vector or the transmitting agents are flies or mosquitoes, which suck blood. Some copepod crustaceans also spread Guinea worm.
The first medicine used to treat filariasis, Diethylcarbamasin citrate (DEC), came into use in the year 1948. Now,albendazole combimned with ivermectin is used to kill adult filarial worms. DEC is a microfilaricide, which kills only the larval form of filarial worms. The DEC changes the morphological features of the microfilarial larva, which are later engulfed by the macrophages (white blood cells). The antibiotic doxycycline was suggested to cure Elephantiasis.
Side effects: The most common side effects of anti-filarial drugs are loss of appetite, nausea, headache, tiredness and giddiness.
Prevention of filariasis can be achieved by taking antifilarial drugs as a preventive measure, if the disease is wide spread in the community. Avoiding mosquito bites using creams and mosquito net bed are safer ways to stay away from filarial infections.
© 2010 Dr.P.Elayaraja