Abstract
INTRODUCTION: Routine immunisation is a cost-effective way to save lives and protect people from disease. Some low-income countries (LIC) achieved remarkable success in childhood immunisation. Yet, previous studies comparing the relationship between economic growth and health spending with vaccination coverage have been limited. We investigated these relationships among LIC to understand what financial changes lead to childhood immunisation changes. METHODS: We identified which financial indicators were significant predictors of vaccination coverage in LIC by fitting regression models for several vaccines, controlling for population density, land area and female years of education. We then identified LIC with high vaccination coverage (LIC+) and compared their economic and health spending trends with other LIC (LIC-) and lower-middle income countries. We used cross-country multi-year regressions with mixed-effects to test financial indicators' rate of change. We conducted statistical tests to verify if financial trends of LIC+ were significantly different from LIC-. RESULTS: During 2014-2018, gross domestic product per capita (p=0.67-0.95, range given by tests with different vaccines), total/private health spending per capita (p=0.57-0.97, p=0.32-0.57) and aggregated development assistance for health (DAH) per capita (p=0.38-0.86) were not significant predictors of vaccination coverage in LIC. Government health spending per capita (p=0.022-0.073) and total/government spending per birth on routine immunisation vaccines (p=0.0007-0.029, p=0.016-0.052) were significant positive predictors of vaccination coverage. From 2000 to 2016, LIC+ increased government health spending per capita by US$0.30 per year, while LIC- decreased by US$0.16 (significant difference, p<0.0001). From 2006 to 2017, LIC+ increased government spending per birth on routine immunisation vaccines by US$0.22 per year, while LIC- increased by US$0.10 (p<0.0093). CONCLUSION: Vaccination coverage success of some LIC was not explained by economic development, total health spending nor aggregated DAH. Vaccination coverage success of LIC+ was associated with increasing government health spending particularly in routine immunisation vaccines.