World Health Organization (WHO) cautious of using BCG vaccine for COVID-19

World Health Organization (WHO) cautious of using BCG vaccine for COVID-19

Part of: GS Prelims and GS-II – Health  

In News:

• The World Health Organization (WHO) highlighted a few critical issues over the use of BCG vaccine for COVID-19 recently.
• They emphasized the importance of randomised controlled trials (RCTs) of the vaccine to understand its safety and efficacy before using it on healthcare workers.

Key takeaways:

• Randomised controlled trials using BCG vaccine are under way in the Netherlands and Australia to find out whether the vaccine can reduce the incidence and severity of COVID-19 among healthcare workers.
• The reasons as to why countries should wait for the results of the BCG vaccine RCTs are:
  • The association of fewer COVID-19 cases in countries that have a universal BCG vaccination programme is based on population rather than individual data. 
  • The beneficial effects of the BCG vaccine given at birth are “unlikely” to reduce the severity of COVID-19 decades later. 
  • It is already known that the virus induces cytokine storm in some patients, leading to further complications — and even death.
  • BCG vaccination is likely to give a false sense of security to people, especially during the pandemic, especially if it is not effective against the novel coronavirus. 
  • Using the vaccine without evidence of its benefits could further decrease vaccine supply to protect children against TB in high-risk countries.

Important value additions:

Randomised controlled trials

• These are quantitative, comparative, controlled experiments in which investigators study two or more interventions in a series of individuals who receive them in random order. 
• The RCT is one of the simplest and most powerful tools in clinical research.

BCG vaccine

• Bacillus Calmette–Guérin (BCG) vaccine is used against tuberculosis (TB).
• In countries where tuberculosis or leprosy is common, one dose is recommended in healthy babies at the time of birth. 

Cytokine storm syndrome (CSS) 

• It is a form of systemic inflammatory response syndrome (SIRS) that can be triggered by a variety of factors such as infections and certain drugs.
• It occurs when large numbers of white blood cells are activated and release inflammatory cytokines, which in turn activate yet more white blood cells.