The impact of meningitis epidemics is enormous and places heavy burden on the health systems of not only Niger, but all the countries within meningitis belt. In major African meningitis epidemics, the attack rate ranges from 100 to 800 per 100,000 inhabitants, but individual communities have reported rates as high as 1/100. Over one million cases of meningitis have been reported in Africa since 1988. In 1996-1997, the largest epidemic wave ever recorded in history swept across Africa, causing over 250,000 cases and 25,000 deaths.

Group A meningococcus has been the main cause of meningitis epidemics in Africa and account for 80-85% of all cases. In 2002, there was an exceptional major outbreak of group W135 meningococcal meningitis in Burkina Faso. Since then, enhanced surveillance activities have shown a dramatic decrease in cases of W135 infection, isolated clusters of group X and group C cases, and a major return of group A meningococcus throughout the meningitis belt. With 41,526 cases reported in 2006, 45,997 cases in 2007, and 88,199 cases in 2009, it has been anticipated that an ever longer epidemic wave may affect in sub-Saharan Africa in the near future.

A detailed socioeconomic study during the 2007 epidemic in Burkina Faso showed that a case of meningitis in a family costs about US $90, one third of a family's annual income. Families with few resources cycle inexorably downward to the next level of poverty. In addition, about 25 percent of survivors have long-term neurologic sequalae such as deafness, hemiplesia, or mental retardation, leaving them less likely to be economically self-sufficient citizens, so often becoming wards of an already financially stretched extended family.

Therefore, through successful vaccination campaigns in Niger and evidence-based data collected during and after the project period, the necessity and impact of introducing the group A meningococcal conjugate vaccine, and safety and effectiveness of the novel vaccine will be proven to health policy-makers in other meningitis belt countries. This will accelerate the acceptance of the novel conjugate vaccine in high-priority areas in sub-Saharan African countries.

Introduction in other core countries, bordering countries, or at-risk countries will be based on a review of the epidemiologic situation and the results of vaccine introduction in countries that have introduced the vaccine initially. Several criteria for ranking meningitis belt countries for the introduction of MenAfriVac™ were identified. These include:

• Disease burden

• Country readiness (existence of an updated comprehensive multi-year plan, quality of district micro-planning, quality of vaccine introduction plan and vaccine management, technical ability of country to successfully implement a national immunization campaign, and good surveillance system and laboratory capacity in the country)

• Participation in clinical trials for vaccine development

• Financial viability, and

• Vaccine availability

Under these criteria, Nigeria, Chad, and Cameroon have been selected as the next candidate for mass vaccination campaigns. Expansion of the campaign to other meningitis belt countries will contribute to following benefits

• Building a platform of mass immunization together with the ministry of health and providing important lessons for the expansion of group A meningococcal conjugate vaccine introduction to other regions in the initial countries

• Investing newly available public health resources in other areas of public health interventions

• Removing the financial drain on families and communities from epidemics and sequelae

• Significantly reducing epidemic meningitis incidence and resulting in other benefits in neighboring countries- especially if the proposed introduction in the initial countries lead to national policies for the adoption of the group A meningococcal vaccine in countries with similar settings.

Reference:
L. Jorda et al, Development of vaccine against meningococcal disease. The Lancet, 2002, volume 359 Issue 9316, p 1499-1508

J. Robbins et al, A rebuttal: epidemic and endemic meningococcal meningitis in sub-Saharan Africa can be prevented now by routine immunization with group A meningococcal capsular polysaccharide vaccine. Pediatric Infectious Disease Journal, 2000, 19(10): pp 945-953

WHO, Control of epidemic meningococcal disease. WHO practical guidelines 2nd edition, 1998

K. E. Nelson, C. Williams, Infectious disease epidemiology: theory and practice 2nd edition, Jones and Barlett Publishers, 2007. p. 643-652

WHO, WHO surveillance bulletins of meningitis. 2009

A. Colombini et al, Costs for households and community perception of meningitis epidemics in Burkina Faso. Clin Infect Dis., 2009, 49(10): 1520-5

Meningitis Investment Case, GAVI Alliance and Fund Board Meeting, 25 June 2008