Onchocerciasis, or river blindness, is a public health epidemic affecting millions of people worldwide. It is found in 36 African countries, and is the second leading infectious cause of blindness. The bite of the blackfly infects the unlucky victim with a parasitic worm, which lives on in the body and eventually causes blindness, among many other problems.
Imagine a once-a-year medication that would kill any parasitic Onchocerca volvulus worms in your system. Now, imagine that this medication cost 40 U.S. cents. And finally, imagine not being able to obtain that 40-cent, vision-preserving medication for yourself or your children.