Current national policies for infant universal bacille Calmette-Guérin vaccination were associated with lower mortality from coronavirus disease 2019

An exciting debate has emerged whether bacille Calmette-Guérin (BCG) vaccination is effective for the coronavirus disease 2019 (COVID-19) pandemic. Some advocated that BCG-vaccinated people are less suffered from the virus because BCG vaccination is recommendedin COVID-19 high burden countries. However, the others objected because this seemingly attractive relationship is explainable with confounding factors. In a multiple regression with 171 countries adjusting socioeconomical and climatic covariates, countries with current universal pediatric BCG policy were associated with 30-fold (95% confidence interval, 17–52) decrease of COVID-19 mortality per population compared to countries without the policy.