For a century, epidemics of meningococcal A meningitis, a bacterial infection of the lining of the brain and spinal cord, have swept across 26 countries in sub-Saharan Africa killing and disabling young people every year. The disease is highly feared on the continent; it can kill or cause severe brain damage within hours.

But just 5 years after an affordable meningitis A vaccine was introduced, its use has led to the control and near elimination of deadly meningitis A disease in the African “meningitis belt.” In 2013, only 4 laboratory-confirmed cases of meningitis A were reported by the 26 countries in the belt, which stretches across the continent from Senegal to Ethiopia.