Researchers have again studied the effectiveness of the BCG vaccine in preventing Covid-19. They concluded that it was not effective, thus confirming the results of other previous studies.
- At the start of the Covid-19 pandemic, BCG appeared as a possible protection because it promotes the immune response.
- Several studies have already shown that BCG is in fact ineffective against Covid-19.
- A new study comparing BCG and a placebo shows that this vaccine does not significantly reduce the risk of Covid-19.
The Bacille Calmette-Guérin, more commonly known as the BCG vaccine, is mainly used to protect against tuberculosis. This vaccine is given to millions of people each year, especially in countries where this disease is still widespread. However, at the start of the Covid-19 pandemic, some researchers speculated that BCG might also protect against other infections, including Covid-19. This idea arose due to the properties of the vaccine which would cause epigenetic changes favoring an immune response against different pathogens.
Previous studies have already demonstrated the ineffectiveness of BCG against Covid-19
A study conducted in Australia in September 2020 has already concluded that BCG was not effective in preventing infections or severe forms of Covid-19. Another study conducted in France in October 2020 showed that BCG had no preventive effect against Covid-19 in healthcare professionals. Yet, despite these results, some countries have continued to administer BCG to their populations, such as Brazil, which launched a vaccination campaign in May 2020, or India, where the vaccine is recommended for people at high risk.
BCG against Covid-19: a new study confirms its ineffectiveness
A new study published in the New England Journal of Medicine confirmed that the BCG vaccine does not protect against infection with SARS-CoV-2, the virus responsible for Covid-19. This study was conducted with nearly 4,000 participants, about half of whom received the BCG vaccine and the other half a placebo. The participants were followed for six months and the researchers analyzed the risk of symptomatic Covid and severe Covid. After six months, the researchers found that the risk of symptomatic Covid was 14.7% in the BCG group and 12.3% in the placebo group. For severe cases requiring hospitalization, the risk was 7.6% in the BCG group and 6.5% in the placebo group. The results indicate that the BCG vaccine did not significantly reduce the risk of Covid-19 compared to placebo.
BCG is not intended to protect against Covid-19
Although BCG has shown promise in preventing some infections, it is not intended to protect against Covid-19. The researchers also warn against its use for purposes other than those indicated, as this could hinder the effectiveness of vaccines specifically designed to combat Covid-19.
The study results underscore the importance of continuing to research specific vaccines to fight the current pandemic, such as messenger RNA vaccines that were developed specifically to prevent Covid-19.