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 (MenAfriVac) was introduced, its use has led to the control and near elimination of deadly meningitis A disease in the African “meningitis belt.”
The vaccine costs less than US$ 0.50 a dose and wherever it has been rolled out, meningitis A has disappeared.
An added benefit is that the vaccine also boosts protective immune responses to tetanus. Tetanus cases in newborn babies have fallen by 25% in countries that completed Meningitis A campaigns in 1 through 29 year olds, according to one of the studies in the collection.
MenAfriVac was introduced as an improvement over older polysaccharide vaccines, which can only be used after epidemics have started, do not protect the youngest children or infants, do not alter disease transmission and provide only short-term protection. Scientists found that 90% of individuals who were vaccinated with MenAfriVac still had protective antibodies in their system 5 years later. Studies show that this is a good predictor of even longer-term protection that scientists will continue to track.
“Countries now need to decide how best to sustain the protection that initial mass vaccination campaigns provided,” said Dr Marie-Pierre Preziosi of WHO, a member of the team that developed the vaccine. “Our experience from other vaccine-preventable diseases has shown that if we let our guard down, these diseases will severely rebound.”