Vaccines to eliminate epidemic meningitis in sub-Saharan Africa
Meningitis is a deadly and debilitating disease that causes an estimated 70,000 cases alone in an area of sub-Saharan Africa known as the meningitis belt, which stretches from Senegal to Ethiopia and has the largest burden of meningitis in the world.
The meningococcus bacterium, or Neisseria meningitidis, causes meningitis, a life-threatening infection in infants, children, and young adults. Even with adequate antibiotic treatment, at least 10 percent of patients die, while up to 20 percent of survivors develop severe complications, including brain damage, hearing loss, or learning disabilities. Left untreated, the disease can lead to fatality rates greater than 70 percent. Vaccination is critical to protecting children from this deadly disease, but existing vaccines are only partially effective against the major meningococcal strains causing disease in the developing world.
Advancing vaccines for broader protection against meningitis
In late 2010, a new meningococcal A conjugate vaccine, MenAfriVac™, was introduced in Burkina Faso, Mali, and Niger. Six months after the introduction of the vaccine, these countries reported the lowest number of confirmed meningitis A cases ever recorded during an epidemic season. The development of this new vaccine was made possible by the Meningitis Vaccine Project, a partnership between PATH and the World Health Organization. The meningococcal A vaccine is now being introduced sequentially in other African countries and will, in all likelihood, significantly reduce the burden of this disease.
Although introduction of the new meningococcal conjugate vaccine should end the public health threat from group A meningococcal disease, other cases caused by non-group A meningitis—15 to 20 percent of meningococcal infections—will continue to occur. Non-group A meningococcal infections will continue to challenge African public health systems unless a vaccine against these infections becomes available at an affordable price.
PATH is working to control these non-group A meningococcal infections through our polyvalent meningitis vaccine project by accelerating the development of an affordable, thermostable, polyvalent meningococcal conjugate vaccine that will prevent disease from non-group A meningococci. Ultimately, our goal is to develop an effective, affordable, and accessible vaccine tailored to needs in the meningitis belt and other underserved countries.
The polyvalent vaccine will have a long shelf life and a stability profile that would allow the vaccine to be stored outside the cold chain. These attributes would dramatically simplify the deployment of meningococcal vaccines in Africa. For example, a polyvalent vaccine of extended shelf life would make it cost-effective to maintain vaccine stocks in several African sites, thus facilitating the mobilization of vaccine shortly after the onset of an epidemic. Through public-private partnerships, PATH is working to develop a safe, effective, and affordable thermostable polyvalent meningococcal vaccine to protect children most in need.