Cost of the national malaria control program and cost-effectiveness of indoor residual spraying and insecticide-treated bed net interventions in two districts of Madagascar.

Abstract

Background: Madagascar has made significant progress in the fight against malaria. However, the number of malaria cases yearly increased since 2012. ITNs and IRS are key interventions for reducing malaria in Madagascar. Given the increasing number of cases and limited resources, understanding the cost-effectiveness of these strategies is essential for policy development and resource allocation.

Methods: Using a societal perspective, this study aims to estimate the cost of the National Malaria Control Program (NMCP) through the first national malaria strategic plan (implemented over the period 2009-2013) and to assess the cost-effectiveness of two individually implemented malaria control interventions (ITNs and IRS) in two districts, Ankazobe and Brickaville. The cost-effectiveness ratio (CER) of ITN intervention was then compared to the CER of IRS intervention to identify the most cost-effective intervention. The cost of the NMCP and the costs incurred in the implementation of each intervention at the district level were initially estimated. On the basis of two results, the CERs of ITN or IRS correspond to the total cost of ITN or IRS divided by the number of people protected or the number of disability-adjusted life years (DALYs) averted. A deterministic univariate sensitivity analysis was conducted to assess the robustness of the results with a discount rate of 2.5% (0-5%) (costs and DALYs) and a 95% CI (person protected).

Results: From 2009 to 2013, the NMCP cost USD 45.4 million (USD 43.5-47.5, r = 0-5%) per year, equivalent to USD 2.0 per capita per year. IRS implementation costs were four times higher than those of ITNs. The CER of IRS per case protected (USD 295.1 [285.1-306.1], r = 0-5%) was higher than the CER of ITNs (USD 48.6 [USD 46.0-51.5, r = 0-5%] in Ankazobe and USD 26.5 [USD 24.8-28.4, r = 0-5%] in Brickaville). The CERs per DALY averted of IRS was USD 427.6 [USD 413.0-546.3, r = 0-5%] in Ankazobe and, for ITNs, it was USD 85.4 [USD 80.8-90.5, r = 0-5%] in Ankazobe and USD 45.3 [USD 42.2-48.4, r = 0-5%] in Brickaville. Compared to the country GDP per capita (USD PPP 1494.6 in 2013), ITN intervention was "highly cost-effective" while the CER for IRS interventions was sensitive to parameter variation (CI, 95% of persons protected), which ranges from highly cost-effective to only cost-effective (USD 291.5-2004, r = 2.5%).

Conclusion: In the Malagasy context, IRS intervention cost more and was less effective than ITN intervention. Willingness to pay for IRS is questioned. A relevant budget impact analysis should be conducted before a potential extension of this intervention.