Bacillus Calmette-Guérin vaccination and clinical characteristics and outcomes of COVID-19 in Rhode Island, United States: a cohort study

Coronavirus disease 2019 (COVID-19) has resulted in a global pandemic, and there is limited data on effective therapies. Bacillus Calmette-Guérin (BCG) vaccine, a live-attenuated strain derived from an isolate of Mycobacterium bovis and originally designed to prevent tuberculosis, has shown some efficacy against infection with unrelated pathogens. In this study, we reviewed 120 consecutive adult patients (≥18 years old) with COVID-19 at a major federally qualified health centre in Rhode Island, United States from 19 March to 29 April 2020. Median age was 39.5 years (interquartile range, 27.0-50.0), 30% were male and 87.5% were Latino/Hispanics. Eighty-two (68.3%) patients had BCG vaccination. Individuals with BCG vaccination were less likely to require hospital admission during the disease course (3.7% vs. 15.8%, P = 0.019). This association remained unchanged after adjusting for demographics and comorbidities (P = 0.017) using multivariate regression analysis. The finding from our study suggests the potential of BCG in preventing more severe COVID-19.