What is BCG vaccine? Is it a new tool to fight COVID-19?
Coronavirus which was first identified in China is now a global pandemic. Many parts of the world are under complete lockdown to contain the spread of the highly contagious disease. Amidst this, the US researchers at the New York Institute of Technology have linked BCG vaccination with fewer COVID-19 cases. The researchers conducted a study and found that the countries without universal policies of BCG vaccination, such as Italy, the Netherlands, and the United States, have been more severely affected compared to countries with universal and long-standing BCG policies such as Japan, Brazil, etc.
What is BCG vaccine?
As per, the US Centres for Disease Control and Prevention, BCG, or bacilli Calmette-Guerin, is a vaccine for tuberculosis (TB) disease. BCG is given between six months after the birth of a child. It was first used in the world in the year 1920.BCG is used in many countries with a high prevalence of TB to prevent childhood tuberculous meningitis and miliary disease.
What does BCG vaccination consist of?
BCG vaccine consists of the strains of bacterium that cause lung tuberculosis in humans. The strain is named Mycobacterium Bovis. During vaccine making, the strength of active bacteria is reduced so that it does not cause disease in healthy people. It is called an active ingredient in the language of medicine. In addition to this, the vaccine contains sodium, potassium and magnesium salts, glycerol and citric acid.
Why BCG vaccination appeared in the study of coronavirus?
The New York Institute of Technology's Department of Biomedical Sciences conducted a study which came out on 21 March. In this study, scientists found that BCG vaccination helps in fighting diseases such as viral infections and sepsis. This raised hopes that BCG vaccination may play an important role in Coronavirus related cases. Scientists arrived at two results after looking at the data from different countries and the health infrastructure:
- In the countries where BCG vaccination is given, there are fewer cases of death due to coronavirus and the countries where BCG started early, have even fewer cases of deaths from Coronavirus comparatively. For example, Brazil started the vaccination of BCG in 1920 and Japan in 1947. Here the risk of spreading corona is 10 times less. At the same time, the 1984 BCG vaccination began in Iran. It is believed that people up to 36 years of age have been vaccinated in Iran, but the elderly are not vaccinated. Because of this, they have a high risk of coronavirus.
- In countries where there is no BCG vaccination, there are more cases of infections and deaths. Such countries include the United States, Italy, Lebanon, Belgium and the Netherlands, where the risk of corona outbreak is 4 times higher.
BCG vaccine in India
The BCG vaccine was first introduced in India as a pilot project in the year 1948. The very next year, in 1949, it was started in schools across the country. In 1962, the National TB Program started n India and children were vaccinated soon after birth across the country. According to this, it can be assumed that a large population in India is BCG vaccinated.
Dr K Srinath Reddy of the Public Health Foundation, Dr Rajendra Prasad Tongra, Advisor to India at WHO and Dr MC Mishra, former Director of AIIMS, believed that India is in a better position as most people in India are vaccinated against the BCG in childhood to prevent TB. It not only protects against TB but is also beneficial in respiratory diseases. The coronavirus also reaches the lungs through the windpipe.
The researchers at the Murdoch Children's Research Institute will be conducting a trial of the Bacillus Calmette–Guerin (BCG) vaccine with 4,000 health care professionals in hospitals around Australia to determine if it can reduce COVID-19 symptoms. They will be taking the blood samples at the start and end of the trial to determine who contracted Coronavirus. These researches have given a ray of hope however we cannot completely rely on the BCG vaccine until its confirmation.