 The BCG vaccine has been shown to have bystander benefits in protecting against heterologous infections and a recent interim analysis of the activate trial suggests protection against respiratory infections in the elderly population. Epidemiologic studies suggest a potential benefit of BCG vaccination on COVID-19 outcomes. A unique natural experiment from differential past BCG vaccination policies between former East and West German states provides evidence that prior BCG vaccination may have a protective effect against COVID-19. Using the COVID-19 international modelling, COMO, consortium model, we estimated a 5% heterologous vaccine efficacy in the highly vaccinated former East Germany. A comparable BCG vaccination campaign undertaken prior to the pandemic in former West Germany, along with known country-wide transmission reduction measures, is associated with a 37% decrease in projected mortality by mid-summer 2020. These findings support a combined heterologous vaccine and non-pharmaceutical interventions, HVI plus NPI, approach to mitigate the SARS-CoV-2 pandemic until SARS-CoV-2 specific vaccines are widely distributed. This article was authored by Daniela Marin-Hanandez, Douglas F. Nixon and Nathaniel Hupert. We are article.tv, links in the description below.