The Meningitis Vaccine Project

Abstract

Epidemic meningococcal meningitis is an important public health problem in sub-Saharan Africa. Current control measures rely on reactive immunizations with polysaccharide (PS) vaccines that do not induce herd immunity and are of limited effectiveness in those under 2 years of age. Conversely, polysaccharide conjugate vaccines are effective in infants and have consistently shown an important effect on decreasing carriage, two characteristics that facilitate disease control. In 2001 the Meningitis Vaccine Project (MVP) was created as a partnership between PATH and the World Health Organization (WHO) with the goal of eliminating meningococcal epidemics in Africa through the development, licensure, introduction, and widespread use of conjugate meningococcal vaccines. Since group A Neisseria meningitidis (N. meningitidis) is the dominant pathogen causing epidemic meningitis in Africa MVP is developing an affordable (US$ 0.40 per dose) meningococcal A (Men A) conjugate vaccine through an innovative international partnership that saw transfer of a conjugation and fermentation technology to a developing country vaccine manufacturer. A Phase 1 study of the vaccine in India has shown that the product is safe and immunogenic. Phase 2 studies have begun in Africa, and a large demonstration study of the conjugate vaccine is envisioned for 2008-2009. After extensive consultations with African public health officials a vaccine introduction plan has been developed that includes introduction of the Men A conjugate vaccine into standard Expanded Programme on Immunization (EPI) schedules but also emphasizes mass vaccination of 1-29 years old to induce herd immunity, a strategy that has been shown to be highly effective when the meningococcal C (Men C) conjugate vaccine was introduced in several European countries. The MVP model is a clear example of the usefulness of a "push mechanism" to finance the development of a needed vaccine for the developing world.