Correlation between COVID-19 case fatality rate and percentage of BCG vaccination: is it true the vaccine is protective?

The Egyptian Journal of Bronchology

Table 1 Correlations of BCG coverage percentage in 183 countries (countries that follow a national BCG immunization program and those that did not have or have ceased their national BCG vaccination programs) and the number of cases/1000 population and number of serious and critical cases/1000 and deaths/1000 population and case fatality rates (in 121 countries)

Variable		BCG coverage%	Cases/1000 population¹	Serious cases/1000 population^2,3	Deaths/1000 population⁴	CFR⁵
BCG coverage	Pearson correlation	1	− 0.592-^**	− 0.256-^**	− 0.608-^**	− 0.388^**
	Sig. (2-tailed)		< 0.001	0.001	< 0.001	< 0.001
	N	180	180	180	180	121
Death rate	Pearson correlation	− 0.608-^**	1	0.321^**	1	1
Death rate	Sig. (2-tailed)	< 0.001	–	< 0.001	1	–
	N	180	183	183	183	121

Coronavirus related statistics were based on data obtained from https://www.worldometers.info/coronavirus/ (according to the latest update on May 2nd, 2020, 20:44 GMT). BCG related statistics were based on Global Health Observatory data repository, BCG Immunization coverage estimates by WHO region, 2018. Doi:10.1371/journal.pmed.1001012.g002
¹Statistically significant negative moderate correlation (R = − 0.592) between BCG coverage and number of cases/1000 (incidence rate) of COVID-19 among the studied countries, P < 0.001
²Statistically significant negative correlation (R = − 0.25) between BCG coverage and number of serious cases/1000 (incidence rate of COVID-19 serious cases) among the studied countries, P = 0.001
³Statistically significant positive correlation (R = 0.32) between death rate and incidence rate of COVID-19 serious cases among the studied countries at P value < 0.001
⁴Statistically significant negative moderate correlation (R = − 0.6) between BCG coverage and death rates at P value < 0.001
⁵Statistically significant negative weak correlation (R = 0.38) between BCG vaccination coverage and case fatality rate of COVID-19 among the studied countries at **=P value < 0.001