A study published this week in the medical journal The Lancet found the MenAfriVac vaccine developed through a partnership led by PATH and the World Health Organization (WHO) had a dramatic impact on cases of meningitis, with the incidence of meningitis of any kind dropping by 94 percent following a mass immunization campaign in Chad, West Africa.
Researchers at the London School of Hygiene & Tropical Medicine evaluated the effectiveness of Chad's mass immunization campaign in 2011 that reached approximately 1.8 million children and young adults with a single dose of the vaccine.
The researchers found that the incidence of meningitis of any kind during the 2012 meningitis season in the three regions where vaccination took place was 2.5 per 100,000 people, compared to an incidence of 43.6 per 100,000 in regions where mass vaccination was not undertaken. In addition, zero cases of deadly group A meningococcal meningitis were detected in the three vaccinated regions.
Meningitis, particularly the A strain, is a major public health threat in Africa's "meningitis belt" stretching from Senegal to Ethiopia. With each epidemic, the disease decimates communities, killing one in ten people who are sickened and leaving one-quarter of survivors severely debilitated. The largest recent outbreak was in 2009 and involved 14 countries, with more than 88,000 suspected cases and more than 5,000 deaths.
In 2001, the Bill & Melinda Gates Foundation provided a ten-year grant to establish the Meningitis Vaccine Project to lead the development, testing, licensure, and widespread introduction of a conjugate vaccine to protect millions from group A meningococcal meningitis.
This study validates the remarkable success of this effort involving collaborators across four continents. "This is one of the most dramatic outcomes from a public health intervention that I have seen during a long career of research in Africa," said study author Professor Brian Greenwood, MD, of the London School of Hygiene & Tropical Medicine.
"This landmark study is further evidence of what a success story this public-private partnership has become in the arena of global health," said Steve Davis, president and CEO of PATH. "When we began this project in 2001, we knew that developing the vaccine was only half the battle. It required intense work to meet rigorous regulatory and technical requirements; to test the vaccine's safety and efficacy; and to strengthen the countries' capacity to administer it for the long haul. We are deeply grateful to all the institutions and the individuals who have made this vision a reality."
More than 100 million people across ten African nations have now received the lifesaving protection of the MenAfriVac vaccine. By 2016, PATH, WHO, and our partners plan to reach more than 300 million children and adults, ages 1 through 29, with the vaccine across the 25 countries of the meningitis belt. Widespread coverage will create "herd immunity" that will protect even those who have not been vaccinated. Immunity with just one dose of the vaccine is expected to last at least ten years.