Evaluation of response strategies against epidemics due to Neisseria meningitidis C in Niger

Halima Boubacar Maïnassara (1) , Garba Idé Oumarou (1) , Bassira Issaka (1) , Ali Sidiki (1) , Issa Idi (1) , Jean-Paul Moulia Pelat (1) , Arnaud Fontanet (2, 3, 4) , Judith E. Mueller (5, 6, 7, 8)

1 CERMES - Centre de Recherche Médicale et Sanitaire (Niamey, Niger)
2 Département Infection et Epidémiologie - Department of Infection and Epidemiology
3 CNAM - Conservatoire National des Arts et Métiers [CNAM]
4 Cellule Pasteur UPMC
5 EHESP - École des Hautes Études en Santé Publique [EHESP]
6 METIS - Département Méthodes quantitatives en santé publique
7 IP - Institut Pasteur [Paris]
8 Epidémiologie des Maladies Emergentes - Emerging Diseases Epidemiology

OBJECTIVE: To inform public health recommendations, we evaluated the effectiveness and efficiency of current and hypothetical surveillance and vaccine response strategies against Neisseria meningitidis C meningitis epidemics in 2015 in Niger. METHODS : We analysed reports of suspected and confirmed cases of meningitis from the region of Dosso during 2014 and 2015. Based on a definition of epidemic signals, the effectiveness and efficiency of surveillance and vaccine response strategies were evaluated by calculating the number of potentially vaccine-preventable cases and number of vaccine doses needed per epidemic signal. RESULTS : A total of 4763 weekly health area reports, collected in 90 health areas with 1282 suspected meningitis cases, were included. At a threshold of 10 per 100 000, the total number of estimated vaccine-preventable cases was 29 with district-level surveillance and vaccine response, 141 with health area-level surveillance and vaccination and 339 with health area-level surveillance and district-level vaccination. While being most effective, the latter strategy required the largest number of vaccine doses (1.8 million), similar to the strategy of surveillance and vaccination at district level (1.3 million), whereas the strategy of surveillance and vaccination at health area level would have required only 0.8 million doses. Thus, efficiency was lowest for district-level surveillance and highest for health area-level surveillance with district-level vaccination. CONCLUSION : In this analysis, we found that effectiveness and efficiency were higher at health area-level surveillance and district-level vaccination than for other strategies. Use of N. meningitidis C vaccines in a preventive strategy thus should be considered, in particular as most reactive vaccine response strategies in our analysis had little impact on disease burden.

Mots clés: Meningitis; Response strategies; Niger; Epidemics; Surveillance

Domaines: Santé publique et épidémiologie

Halima Boubacar Maïnassara, Garba Idé Oumarou, Bassira Issaka, Ali Sidiki, Issa Idi, et al.. Evaluation of response strategies against epidemics due to Neisseria meningitidis C in Niger. Tropical Medicine and International Health, 2017, 22 (2), pp.196-204. ⟨10.1111/tmi.12815⟩. ⟨hal-02461241⟩