Large-scale delivery of seasonal malaria chemoprevention to children under 10 in Senegal: an economic analysis

Abstract

Seasonal Malaria Chemoprevention (SMC) is recommended for children under 5 in the Sahel and sub-Sahel. The burden in older children may justify extending the age range, as has been done effectively in Senegal. We examine costs of door-to-door SMC delivery to children up to 10 years by community health workers (CHWs). We analysed incremental financial and economic costs at district level and below from a health service perspective. We examined project accounts and prospectively collected data from 405 CHWs, 46 health posts, and 4 district headquarters by introducing questionnaires in advance and completing them after each monthly implementation round. Affordability was explored by comparing financial costs of SMC to relevant existing health expenditure levels. Costs were disaggregated by administration month and by health service level. We used linear regression models to identify factors associated with cost variation between health posts. The financial cost to administer SMC to 180 000 children over one malaria season, reaching ∼93% of children with all three intended courses of SMC was $234 549 (constant 2010 USD) or $0.50 per monthly course administered. Excluding research-participation incentives, the financial cost was $0.32 per resident (all ages) in the catchment area, which is 1.2% of Senegal's general government expenditure on health per capita. Economic costs were 18.7% higher than financial costs at $278 922 or $0.59 per course administered and varied widely between health posts, from $0.38 to $2.74 per course administered. Substantial economies of scale across health posts were found, with the smallest health posts incurring highest average costs per monthly course administered. SMC for children up to 10 is likely to be affordable, particularly where it averts substantial curative care costs. Estimates of likely costs and cost-effectiveness of SMC in other contexts must account for variation in average costs across delivery months and health posts.

Keywords: Seasonal malaria chemoprevention (SMC); Sub-Saharan Africa; campaigns; community health workers; cost function; cost variation; intermittent preventive treatment; malaria; mass drug administration; primary health care.

Figure 1.

Total and average costs by health post with cost drivers. Health posts are ordered (left to right) in both graphs from largest to smallest total economic costs, including research participation incentives. District-level costs have been divided evenly across the health posts within each district. As total costs decrease, the average cost per course administered tends to increase, although there is some variation in this trend.

Figure 2.

Total economic cost vs the number of courses administered at each health post. The figure illustrates the variation in the total costs incurred for SMC administration between health posts. Costs incurred at the district level are allocated equally across health posts in that district. Research participation incentives paid directly to head nurses and district health staff for trial participation are included as they are likely to have led to more assiduous implementation. The 46 health posts are presented with a different marker for each of the 4 districts. Dashed line: mean total economic cost per health post

Figure 3.

Economies of scale: average economic cost per course administered vs the number of courses administered at each health post. The figure illustrates the variation in the average economic cost per course of SMC administered between health posts. The upper figure presents data on a standard arithmetic scale and the lower figure illustrates the same data with both the x-axis and y-axis presented on a logarithmic scale. Costs incurred at the district level are allocated equally across health posts in that district. Research participation incentives paid directly to head nurses and district health staff for trial participation are included as they are likely to have led to more assiduous implementation. The 46 health posts are presented with a different marker for each of the 4 districts. Dashed line: mean economic cost per course administered across the entire implementation area.