River Blindness

treatment is ivermectin [given every 6 months for the life span of the adult worms (i.e., 10–15 years) or for as long as the infected person has evidence of skin or eye infection].
Ivermectin kills the larvae & prevents them from causing damage but it does NOT kill the adults. 
There is a promising treatment using doxycycline that kills the adult worms by killing the Wolbachia bacteria on which the adult worms depend in order to survive.
If you are infected, it is possible that your doctor will want to treat you both with ivermectin & doxycycline. 
Before any treatment is begun, however, you need to make sure that you are NOT also infected with Loa loa, another filarial parasite found in central Africa that is sometimes found in the same areas where O. volvulus is found, because Loa loa can be responsible for severe side effects to medications used to treat onchocerciasis" (river blindness), per https://www.cdc.gov/parasites/index.html