 From VOA Learning English, this is the health report in special English. Nigerian doctor Ucha Amazigo has received the Prince Mahidan Award for Outstanding Efforts in Public Health. Dr. Amazigo recently traveled to Thailand to receive the award. She has been a leader in sub-Saharan Africa in the fight against the disease known as river blindness. The disease begins when people are bitten by the black flies that spread the infection. The disease is known as river blindness because the flies live near fast-moving rivers and streams. Tiny worms spread throughout the body. This insights the body's immune system to attempt to fight the invaders. But the body's intense response can destroy the eye nerves. The infection can cause not only blindness, it also causes a painful skin disease. The cause of river blindness was first identified in Guatemala almost 100 years ago. The disease continues to be a serious health problem in many African nations and in Yemen. Medical treatment lasting as long as 20 years is necessary to keep victims free from the parasite that causes the disease. Dr. Amazigo is a former director of the World Health Organization's African Program for Oncocerecius Control. That is the medical name for river blindness. Dr. Amazigo organized local treatment programs in communities. Now, 117,000 communities under 19 African governments treat the disease locally. In 1987, the drug manufacturer, Merck, launched a program to provide a medicine called ivermectin to everyone affected by the disease. The company said it would provide the treatment for free as long as necessary through the community-directed program. For VOA Learning English, I'm Carolyn Presuti.