Study Finds BCG Vaccination Does Not Lower Risk of COVID-19 Among Healthcare Workers

A recent randomized controlled trial has found that the Bacille Calmette-Guerin (BCG) vaccine does not result in a lower risk of contracting COVID-19 among healthcare workers compared to a placebo. The study also found that vaccination with the BCG vaccine did not change the risk of symptomatic or severe COVID-19 among healthcare workers. The BCG vaccine was initially developed to prevent tuberculosis infection and has been proposed as a preventative measure for respiratory illness in both children and adults. However, there is a knowledge gap in understanding whether the incidence and severity of COVID-19 is lower in those who previously received the BCG vaccine.

Study Overview

The international, double-blind, placebo-controlled trial studied participants who were randomly assigned in a 1:1 ratio to receive either the intradermal BCG vaccine or saline placebo. Patients were followed for 12 months and those who had previously tested positive for SARS-CoV-2, had contraindications to the BCG vaccine, received the BCG vaccine within the past year, received any other live attenuated vaccine within the past month, or any COVID-19–specific vaccine were excluded from the study. The primary outcome measured was the incidence of symptomatic COVID-19 and the incidence of severe COVID-19 by six months follow-up.

Study Findings

Based on the primary analysis, the estimated risk of symptomatic COVID-19 by 6 months was 14.7% in the BCG group and 12.3% in the placebo group. The risk difference was 2.4% with a 95% confidence interval (CI) of −0.7 to 5.5. When looking at the risk of severe COVID-19, the estimated risk of severe COVID-19 by six months was 7.6% in the BCG group and 6.5% in the placebo group. The risk difference was 1.1% with a 95% CI of −1.2 to 3.5. Additionally, the hazard ratio for any COVID-19 episode in the BCG group as compared with the placebo group was 1.23 with a 95% CI of 0.96 to 1.59.

The study was limited by the inability to recruit the planned sample, making it underpowered and susceptible to type II error. Nevertheless, these findings are significant as they demonstrate that the BCG vaccine does not confer any protective benefit among healthcare workers in preventing symptomatic or severe COVID-19.

Conclusion

The study’s findings may help guide future COVID-19 prevention strategies. While the BCG vaccine remains an important tool in preventing tuberculosis, it does not appear to be effective in preventing COVID-19 among healthcare workers. Further research is needed to fully understand the relationship between the BCG vaccine and COVID-19 prevention.

1. COVID-19 vaccine effectiveness
2. BCG vaccine and COVID-19
3. Healthcare worker COVID-19 protection
4. BCG vaccine and healthcare worker risk
5. BCG vaccine for COVID-19 prevention

News Source : 2 Minute Medicine
Source Link :BCG vaccine does not lower risk of COVID-19 infection among healthcare workers/