On the first day of a remarkable campaign to stop one of the most devastating diseases in Africa, five months ago, I wrote from Burkina Faso in the heart of West Africa.

On December 6, 2010, millions of people lined up in one of the poorest countries in the world to receive the new MenAfriVac™ vaccine, which will protect them from the most virulent strain of meningitis on the continent, meningococcal A meningitis.

Epidemics of meningococcal meningitis have decimated Africa for more than a century, causing hearing loss, mental retardation, epilepsy, and death. To eradicate them, the government of Burkina Faso committed to immunizing the entire target population—ages 1 to 29—within two weeks. So eager were people to receive the vaccine that, in some areas, more than three-fourths of the target population was vaccinated in just three days!

From Burkina Faso, the vaccine was rolled out in Mali and Niger—two more of the hardest-hit countries in what is known as the “meningitis belt.” Within a month, almost 20 million people had been vaccinated. This massive and rapid campaign could not have happened without untold numbers of dedicated people, from the town criers who gave advance notice in villages to the nurses who rose before dark and spent 12-hour days vaccinating every person who came.

The success of the campaign also depended upon an innovative vaccine development model spanning four continents. Partners in this effort ranged from the Meningitis Vaccine Project, to funders like the Bill & Melinda Gates Foundation, to the Serum Institute of India Ltd., which committed to making the vaccine for less than $0.50 (U.S.) per dose. Finally, critical to the rollout was the GAVI Alliance, which supports the introduction of vaccines in the developing world.

Now the GAVI Alliance has announced that it is releasing $100 million to roll out MenAfriVac in Cameroon, Chad, and Nigeria before the 2012 epidemic season begins. Chad and Nigeria are both hyperendemic, while northern Cameroon’s location between the two countries means preventive immunization there will help stop the spread of any epidemic.

This is the beginning of the end of meningitis epidemics in this part of the world.

During this year’s meningitis season, which goes from January to May, the number of confirmed cases in the countries where the campaign was launched is already considerably lower than usual. But to conquer the disease, we must vaccinate an additional 300 million people by 2015.