Associating the scale-up of insecticide-treated nets and use with the decline in all-cause child mortality in the Democratic Republic of Congo from 2005 to 2014

Background To reduce the malaria burden and improve the socioeconomic status of its citizens, the Democratic Republic of Congo scaled up key malaria control interventions, especially insecticide-treated nets (ITNs), between 2005 and 2014. Since then, the effects of these interventions on malaria mortality and morbidity have not been assessed. This study aimed to measure the impact of the National Malaria Control Programme’s efforts and to inform future control strategies. Methods The authors used data from the Demographic and Health Surveys 2007 and 2013–2014 to assess trends in all-cause childhood mortality (ACCM) against trends in coverage of malaria interventions at national and subnational levels. The authors used the plausibility argument to assess the impact of the malaria control interventions and used Kaplan–Meier survival probability and Cox proportional hazard models to examine the effect of ITN ownership on child survival. Contextual factor trends affecting child survival were also considered. Results Countrywide, household ownership of at least one ITN increased, from 9% in 2007 to 70% in 2013–2014. All provinces experienced similar increases, with some greater than the national level. ITN use increased between 2007 and 2013–2014 among children under five (6% to 55%). Severe anaemia (haemoglobin concentration < 8 g/dl) prevalence among children aged 6–59 months significantly decreased, from 11% (95% confidence interval [CI] 9–13%) in 2007 to 6% (95% CI 5–7%) in 2013–2014. During the same period, ACCM declined, from 148 (95% CI 132–163) to 104 (95% CI 97–112) deaths per 1000 live births. The decline in ACCM was greater among children aged 6–23 months (relative reduction of 36%), compared to children aged 24–59 months (relative reduction of 12%). Cox regression indicated that household ownership of at least one ITN reduced the risk of mortality by 24% among children under five (risk ratio = 0.76, 95% CI 0.64–0.90). Contextual factor analysis revealed marginal improvements in socioeconomic indicators and other health interventions. Conclusions Given the patterns of the coverage of malaria control interventions, patterns in ACCM by province, and marginal improvements in contextual factors, the authors conclude that the malaria control interventions have plausibly contributed to the decrease in ACCM in the Democratic Republic of Congo from 2005 to 2014.