The burden of acute respiratory infection in children under 5 attributable to economic inequality in low- and middle-income countries.

Background: Quantifying the disease burden among children that could potentially be reduced through improvements in individual economic status and regional economic equality can greatly benefit policy making and resource allocation. However, such quantification has rarely been done. This study aimed to assess the inequality-related burden of acute respiratory infection (ARI) (the leading cause of child mortality in low- and middle-income countries (LMICs)) among under five children.

Methods: This study integrated the Demographic and Health Survey data from 53 countries and linked individual records to a novel proxy of economic development status, the satellite night-time light (NTL). We assessed the number of children affected by ARI attributable to within-country economic disparities (eg, NTL

Results: The odds of experiencing ARI were decreased significantly (3.5% ((95% confidence interval (CI) 1.4% to 4.4%)) for every 10-digit number increase in NTL. The exposure-response function showed constant decreasing in the risk of ARI as NTL level increases. It is estimated that within-country economic disparities contributed to 11.0% (95% CI 6.1% to 15.6%) of all children affected by ARI in 2001, which was decreased to 8.1% (95% CI 4.2% to 11.8%) in 2019. In contrast, the inequality-related burden remained stable. In sub-Saharan Africa, it increased from 4.8% (95% CI 1.7% to 8.0%) in 2001 to 6.8% (95% CI 3.0%-9.8%) in 2019. Eliminating within-country inequality would have avoided 522 136 (95% CI 2 66 760 to 7 57 414) cases of ARI among children across the 133 LMICs in 2019.

Conclusion: Our study revealed a protective effect of economic status on preventing ARI in children under 5 years of age. The considerable burden of childhood ARI was attributable to the economic inequality in LMICs. Optimising the allocation of economic resources can safeguard child health.