In Africa south of the Sahara, all-cause under-5 mortality is an important indicator of the burden of malaria. Children in this age group are those most likely to develop severe disease and to be at risk of dying from malaria.

In addition to the around 18% of all-cause deaths in African children under 5 years of age that are directly attributable to malaria, an even greater proportion of child deaths is probably indirectly related to malaria: repeated malaria infections contribute to the development of severe anaemia and make

young children more susceptible to severe outcomes of other common childhood illnesses such as diarrhoea and respiratory diseases. In addition, malaria in pregnant women contributes to low birth weight, a major risk factor for infant mortality. Further demonstration of the importance of malaria as a contributor to deaths among young children is the series of community-randomized ITN trials that demonstrated a reduction in all-cause under-5 mortality by up to 25%. National household surveys provide more comprehensive data on all-cause under-5 mortality than is available for malaria-specific mortality, which is difficult to define and measure at a population-level with adequate specificity and sensitivity.

Throughout Africa south of the Sahara, the decrease in all-cause under-5 mortality that was apparent during the 1970s and 1980s leveled off in the 1990s. Besides HIV/AIDS, increased mortality caused by malaria in the 1990s compared with earlier decades is probably among the explanations for this trend.