Exploring the role of bacillus calmette-guerin vaccination in protection against COVID-19

Background: In recent studies, it has been established that countries having Bacillus Calmette-Guerin (BCG) vaccination programs reported less COVID-19 cases and deaths per population Preliminary studies suggest that BCG vaccination could upregulate the vaccine-induced immunity against SARS-CoV-2. Hence, the recent study was aimed to determine the association of BCG vaccine with the development of COVID-19 in health care workers. Methods: The participants included in the study were healthcare workers (doctors, paramedics, and other supporting staff) working in the high and low-risk zones of COVID-19 in the hospital. The Graph Pad statistical analysis tool was used to determine the association of preliminary BCG vaccination with their COVID-19 status. Results: A total of 200 health care workers working in different departments of the hospital were enrolled in the study. The relative risk of COVID-19 positivity in BCG vaccinated versus unvaccinated was 0.79 (0.50-1.25). There was also a significant negative correlation between two groups. The relative risk of COVID-19 positivity in those with a BCG scar was 0.63 (0.44-0.92). The relative risk of COVID-19 infection in those with a history of tuberculosis was 1.08 (0.56-2.09). Conclusion: The present study did not support the beneficial effect of BCG vaccine in protection against the development of COVID-19 disease.