Impact of MenAfriVac on Meningococcal A Meningitis in Cameroon: A Retrospective Study Using Case-by-Case-Based Surveillance Data from 2009 to 2015

• Published in: Journal of Tropical Medicine
• Main Authors: Bouba Gake, Bonaventure Babinne Graobe, Bouba Abdouraman, Crescence Satou Ngah, Ahmadou Aissatou, Nelly-Michèle Gake, Elise Claudine Seukap, Elias Nchiwan Nukenine, Alain G. Etoundi Mballa, Marie-Christine Fonkoua, Jean-Pierre Lombart
• Format: Article in Journal/Newspaper
• Language: English
• Published: Hindawi Limited 2021
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Arctic
• Online Access: https://doi.org/10.1155/2021/4314892; https://doaj.org/article/586d74e38475409b941d53a1b90e5ae4

Meningococcal meningitis is a public health concern in Africa. Conjugated vaccine against serogroup A Neisseria meningitidis (MenAfriVac) was used in mass vaccination and was proved to have a good impact in the meningitis belt. There is a lack of information about the impact of this intervention in Cameroon after mass vaccination was undertaken. This study aimed at filling the gap in its unknown impact in Cameroon. A retrospective longitudinal study using biological monitoring data of case-by-case-based surveillance for meningitis was obtained from the National Reference Laboratories from 1 January 2009 to 20 September 2015. Immunization coverage data were obtained from Regional Public Health Delegations where immunizations took place. We compared the risks of vaccine serogroup occurrence before and after vaccinations and calculated the global impact using Halloran’s formula. Annual cases of meningitis A decreased gradually from 92 in 2011 to 34 in 2012 and then to 1 case in 2013, and since 2014, no cases have been detected. The impact was estimated at 14.48% (p=0.41) in 2012 and then at 98.63% (p<0.0001) after the end of vaccinations in 2013. This survey confirms the effectiveness of the MenAfriVac vaccine in Cameroon as expected by the WHO. The surveillance must be pursued and enhanced to monitor coming immunizations measures with multivalent conjugated vaccines for this changing threat.