The disease onchocerciasis, a major cause of blindness which affects some 37 million people worldwide, can be wiped out using drugs, says the UN health agency.
New studies showed treatment with the drug ivermectin stopped further infections and transmission of the disease in three areas of Africa, the World Health Organization said.
Scientists hailed the findings a "historic milestone" in the fight against the disease also known as river blindness, because it is spread by blackfly which breeds in rivers.
People in Africa, where 99 percent of infections occur, had been given free treatments of ivermectin since its development in 1987 by drug manufacturer Merck.
The drug kills the larvae of the parasite that causes the disease, but not the adult worms, so scientists thought treatments were needed every six months or year to keep it under control.
Around 60 million people were treated in 26 African countries in 2008.
But the new studies, published Tuesday in the journal PLoS Neglected Tropical Diseases, suggest it can be wiped out with a long enough course of ivermectin.
They showed that after 15 to 17 years of regular treatment, only a few infections remained.
Treatment was stopped in the three test areas, in Mali and Senegal and follow-up assessments between one-and-a-half and two years later showed no further infections or transmissions of the disease.
"Although further studies are needed to determine to what extent these findings can be extrapolated to other areas in Africa, the principle of onchocerciasis elimination with ivermectin treatment has been established," the WHO said in a statement.
The studies were carried out by research teams from the ministries of health in Mali and Senegal, in collaboration with the WHO multi-disease surveillance center in Burkina Faso.
Main funding came from the Bill & Melinda Gates Foundation.