At least 120 million people in 73 countries worldwide are estimated to be infected with filariasis parasites.
The most widespread is Wuchereria bancrofti, which affects about 100 million people in Africa, India, Southeast Asia, and South America.
In the Bangladeshi flood plains, the disease is present now in 23 districts. About 20 million are already infected there, most of which are incapacitated and another 30 million are at risk of infection.
I visited the worlds only Lymphatic Filariasis Hospital in rural Bangladesh to see how the disease is being treated.