COVID-19 Death and BCG Vaccination Programs Worldwide

Abstract

Several clinical trials are being conducted worldwide to investigate the protective effect of the bacillus Calmette-Guérin (BCG) vaccine against death in healthcare providers who are working directly with coronavirus disease 2019 (COVID-19) patients. Clinical studies suggested that certain live vaccines, particularly the BCG vaccine, could reduce the mortality due to other diseases caused by non-targeted pathogens, most probably through the nonspecific effects (heterologous effects). By the end of May 2020, the available information on the COVID-19 pandemic indicated the great effect of the BCG vaccine in reducing the number of COVID-19 death cases. The occurrence of death due to COVID-19 was found to be 21-fold lower in countries with a national BCG vaccination policy than in countries without such a policy, based on the medians of COVID-19 death case per 1 million of the population in these two groups of countries (p<0.001, MannWhitney test). Therefore, it can be concluded that the early establishment of a BCG vaccination policy in any country is a key element in reducing the number of COVID-19 and tuberculosis death cases.

Keywords: BCG Vaccine; COVID-19 Death Cases; COVID-19 Mortality; COVID-19 Pandemic; Coronavirus.

Fig. 1.

Summary of coronavirus disease 2019 (COVID-19) death case per million of population in countries with more than 10,000 COVID-19 cases in the presence and absence of Bacillus Calmette-Guérin (BCG) vaccination policies, as per the World Health Organization situation report on 28 May 2020. p-values represent results of Mann-Whitney comparison between BCG and non-BCG countries.