Quantifying the indirect effects of key child survival interventions for pneumonia, diarrhoea, and measles

To date many studies have measured the effect of key child survival interventions on the main cause of mortality while anecdotally reporting effects on all-cause mortality. We conducted a systematic literature review and abstracted cause-specific and all-cause mortality data from included studies. We then estimated the effect of the intervention on the disease of primary interest and calculated the additional deaths prevented (i.e. the indirect effect). We calculated that insecticide-treated nets have been shown to result in a 12% reduction [95% confidence interval (CI) 0·0-23] among non-malaria deaths. We found pneumonia case management to reduce non-pneumonia mortality by 20% (95% CI 8-22). For measles vaccine, seven of the 10 studies reporting an effect on all-cause mortality demonstrated an additional benefit of vaccine on all-cause mortality. These interventions may have benefits on causes of death beyond the specific cause of death they are targeted to prevent and this should be considered when evaluating the effects of implementation of interventions.