The burden of malaria mortality among African children in the year 2000

Abstract

Background: Although malaria is a leading cause of child deaths, few well-documented estimates of its direct and indirect burden exist. Our objective was to estimate the number of deaths directly attributable to malaria among children <5 years old in sub-Saharan Africa for the year 2000.

Methods: We divided the population into six sub-populations and, using results of studies identified in a literature review, estimated a malaria mortality rate for each sub-population. Malaria deaths were estimated by multiplying each sub-population by its corresponding rate. Sensitivity analyses were performed to assess the impact of varying key assumptions.

Results: The literature review identified 31 studies from 14 countries in middle Africa and 17 studies and reports from four countries in southern Africa. In 2000, we estimated that approximately 100 million children lived in areas where malaria transmission occurs and that 803 620 (precision estimate: 705 821-901 418) children died from the direct effects of malaria. For all of sub-Saharan Africa, including populations not exposed to malaria, malaria accounted for 18.0% (precision estimate: 15.8-20.2%) of child deaths. These estimates were sensitive to extreme assumptions about the causes of deaths with no known cause.

Conclusions: These estimates, based on the best available data and methods, clearly demonstrate malaria's enormous mortality burden. We emphasize that these estimates are an approximation with many limitations and that the estimates do not account for malaria's large indirect burden. We describe information needs that, if filled, might improve the validity of future estimates.

Figure 1

Seven sub-populations in Africa with different risks of dying from malaria

Figure 2

Distribution of malaria mortality rates as a function of parasite prevalence among studies of childhood mortality from middle Africa, 1980–2001 (74 estimates from 20 Group A studies; all studies except one were conducted in rural areas). The dashed vertical line indicates the chosen threshold between ‘low-intensity’ (i.e. parasite prevalence <25%) and ‘high-intensity’ (i.e. parasite prevalence ≥25%) malaria transmission

Figure 3

Distribution of malaria mortality rates as a function of study year (46 rates from 15 Group A studies; all studies of rural populations in middle Africa exposed to high-intensity malaria transmission) The dashed horizontal lines indicate the predicted malaria mortality rate from the final Poisson regression model for rural populations in middle Africa exposed to high-intensity malaria transmission: the predicted rate is constant over study years 1980–89 (7.43 per 1000 per year) and constant over study years 1990–2001 (11.36 per 1000 per year)