Interesting real world experiment in East and West Germany.
From the nature article...
"We read with great interest the recent thorough study from Miller et al. [1], who reported a beneficial impact of early Bacillus CalmetteGurin (BCG) vaccination, and linked morbidity and mortality due to SARS-CoV-2 with BCG vaccination policy. They found that countries without policies of universal BCG vaccination (like Italy, the Netherlands, or the United States) have been more severely affected compared with countries with universal and long-standing BCG policies. Since senior citizens are particularly sensitive to COVID-19, newborn vaccination programs implemented in the 1940s and 1950s should be the most beneficial. Thus, we were impressed by the linear correlation between the year of the establishment of universal BCG vaccination and the mortality rate presented by Miller et al. [1]. In our view, this is a convincing argument for the hypothesis that the earlier the vaccination policy was established, the larger the segment of the elderly population being protected.
We would like to make the scientific community aware of a unique historical circumstance in Germany, where divergent BCG vaccination policies existed in the politically divided country (19491989) before German reunification in 1990. In East Germany, BCG vaccination programs were established by the communist government in 1951, and soon became compulsory in 1953, leading to near-universal (99.8%) BCG vaccination of newborns by day 3. By contrast, voluntary BCG vaccination (recommended since 1955) was far less common in West Germany, due to low incidence of the disease after the Second World War. In early years, only 720% of all newborns became BCG-vaccinated in Western Germany, with almost complete cessation of vaccination between 1975 and 1977 (Fig. 1a). Thus, we believe that the comparison of morbidity and mortality of SARS-CoV-2 would be particular informative in the light of the rather uniform genetic, social, and cultural background. Here, we record those data in formerly East and West German federal states (excluding Berlin, Fig. 1b). Our observations strongly support the analysis from Miller et al., and point toward BCG vaccination having a protective effect. "
