Lymphatic filariasis

Lymphatic filariasis, commonly known as elephantiasis, is a painful and profoundly disfiguring disease. While the infection is usually acquired in childhood its visible manifestations occur later in life, leading to temporary and permanent disability. Lymphatic filariasis has a major social and economic impact on endemic countries.

The disease is caused by three species of nematode thread-like worms - Wuchereria bancrofti and Brugia malayi and Brugia timori, known as filariae. Male worms measure about 3-4 centimetres in length and female worms between 8-10 centimetres. Both male and female worms live together and form 'nests' in the human lymphatic system, the network of nodes and vessels that maintain the delicate fluid balance between the tissues and blood. The lymphatic system is an essential component of the body's immune system.

Filariae are responsible for a variety of clinical manifestations, including lymphoedema of the limbs, genital disease (hydrocele, chylocele and swelling of the scrotum and penis) and recurrent acute disease episodes. The vast majority of infected people are asymptomatic but virtually all of them have sub clinical lymphatic damage and as many as 40% have renal involvement with proteinuria and haematuria.

The infection can be treated with drugs. However, chronic conditions may not be curable by anti-filarial drugs and require other measures, eg. surgery for hydrocele, care of the skin and exercise to increase lymphatic drainage in lymphoedema.

Annual treatment of all individuals at risk (individuals living in endemic areas) with recommended anti-filarial drugs combination of either diethyl-carbamazine citrate (DEC) and albendazole, or ivermectin and albendazole; or the regular use of DEC fortified salt can prevent occurrence of new infection and disease.