Antibody persistence in the population after mass vaccination with group A meningococcal conjugate vaccine in Burkina Faso
Dr Judith Mueller
- Start Date:
21 July 2011
Agence de Médecine Préventive, Ouagadougou, Burkina Faso
From late 2010 on, group A meningococcal (MenA) conjugate vaccines will be introduced by mass campaigns into the 1- to 29-year-old population of Burkina Faso to prevent epidemic meningococcal meningitis. Information on antibody persistence in vaccinees will be needed to determine the optimal interval of repeat mass campaigns during subsequent years. In order to capture various effects that may affect the magnitude and duration of population immunity, we propose to evaluate antibody persistence after vaccine introduction by repeated cross-sectional seroprevalence surveys in the general population.
Each survey will include 700 individuals aged 1-39 years randomly sampled from the general population of Bobo-Dioulasso, Burkina Faso. The surveys will be conducted in 2011 (approximately 6 months after the mass campaign with MenA conjugate vaccine), 2013 (30 months post-vaccination) and 2015 (54 months post-vaccination). Serum samples will be obtained and a brief questionnaire administered.
Serological analyses will be performed on all serum samples, including measurement of anti-A IgG concentration and anti-A serum bactericidal antibody titers.
Data will be analysed to determine the age-specific proportion of putatively protected individuals in the population at each survey, based on established correlates of protection, and to determine risk factors for poor antibody persistence. We then will model the data to obtain estimates of the number of cases prevented at different intervals of mass vaccination campaigns. The expected outcome is a recommendation for the optimal interval of mass vaccination campaigns.