Philariasis (filariasis) is an infectious parasitic disease that is prevalent to tropical regions. This disease is caused by a thread-like filarial worms and it is transmitted by the flies or mosquitoes (culex, specific to urban regions, anopheles, specific to rural regions and aedes, specific to Pacific islands).
There exists three types of filariasis, depending on the region occupied by one of the 9 filarial worms: lymphatic filariasis, serous cavity filariasis and subcutaneous filariasis.
In lymphatic filariasis, the worms brugia timori, brugia malayi and wuchereria bancrofti occupy the lymph nodes. In subcutaneous filariasis, the worms african eye worm and guinea worm are located in the subcutaneous fat layers of the skin. In serous cavity filariasis, the worms mansonella can be found in the serous cavity of abdomen.
The infection can be diagnosed in blood samples that are usually taken by night, since microfilaria circulate by night, when flies and mosquitoes sting.
The symptoms of lymphatic filariasis are thickening of the skin and underlying tissues and edema (fluid accumulation) of the lower extremities and permanent disabilities. The symptoms of subcutaneous filariasis are arthritis, skin rashes, blindness. The symptoms of serous cavity filariasis can be easily confounded with the symptoms of subcutaneous filariasis, the difference being made by the abdominal pains caused by the worms that reside in the deep tissues of the serous cavity of the abdomen.
The treatment of filariasis is a single dose of 400 mg albendazole and 6 mg/kg diethylcarbamazine citrate, this combined dose eliminating the microfilariae from the bloodstream.