Uncovering COVID-19 vaccine acceptance and intent in 15 developing countries: a multi-level, clustered analysis of six months of repeated, cross-sectional data

BACKGROUND: COVID-19 vaccination hesitancy is antithetical to preventing communicable disease. The study's aim was to determine social ecological factors associated with vaccination acceptance / intent in select developing countries. METHODS: To examine vaccine acceptance / intent in fifteen developing countries, data was sourced from the Global COVID-19 Trends and Impacts Survey and analyzed with a multi-level, clustered, cross-sectional design. Weighted Generalized Additive Modeling (GAM) with 1,000 stratified cluster bootstraps mitigated intra-cluster correlation and temporal dependencies. RESULTS: Statistically significant linear variables included those age 55 + (OR = 1.204, 95% CI [1.095, 1.324], p < 0.001) and identification as female (OR = 1.538, 95% CI [1.448, 1.630], p < 0.001), which were responsible for increased odds of vaccine acceptance / intent. Percent Fear of Vaccine Side Effects (EDF = 2.50, p < 0.001) demonstrated a nonlinear decline in vaccine acceptance / intent. Time (Month) (EDF = 1.94, p < 0.001) was associated with a concave parabolic trend. Cultural Principal Components (PCs) 1-3, respectively, (EDF = 3.97, p < 0.001). EDF = 4.87, p < 0.001), and (EDF = 4.95, p < 0.001) demonstrated oscillating patterns of vaccine acceptance / intent depending upon cultural score direction and magnitude. All PCs demonstrated lower levels of vaccination acceptance / intent with no definitive cultural leaning. There was, however, a push-pull effect among all three dimensions, demonstrating PCs either drove or suppressed vaccination acceptance / intent. CONCLUSIONS: Vaccine decision-making complexities are associated with cultural and individual influences. Such findings could inform future vaccine campaign strategies.