Context: Recently, Doctors and scientists in India have expressed caution on a study, which argues that countries that have deployed the BCG-tuberculosis vaccine in their immunisation programmes have seen fewer deaths from COVID-19.
Key Findings of the study

• The study argues that 55 middle and high-income countries chosen for the analysis, that have a current universal BCG policy had 0.78 deaths per million people, whereas middle and high income countries that never had a universal BCG policy (5 countries) had a larger mortality rate, with 16.39 deaths per million people.
• India, while having a universal BCG policy in place and relatively fewer deaths as a proportion of confirmed coronavirus infections.
• Italy where the COVID-19 mortality is very high, never implemented universal BCG vaccination.
• On the other hand, Japan (and which has a BCG policy since 1947) had one of the early cases of COVID-19 but it has maintained a low mortality rate despite not implementing the most strict forms of social isolation.
• Spain, France, the United States, Italy and the Netherlands don’t have universal BCG policies and have seen many deaths from COVID-19.However, the study is not backed yet.
• BCG Vaccine confers a strong immune response

About BCG Vaccine

• Bacillus Calmette–Guérin (BCG) vaccine is a vaccine primarily used against tuberculosis (TB).
• In countries where tuberculosis or leprosy is common, one dose is recommended in healthy babies as close to the time of birth as possible.
• In areas where tuberculosis is not common, only children at high risk are typically immunized, while suspected cases of tuberculosis are individually tested for and treated.
• Adults who do not have tuberculosis and have not been previously immunized but are frequently exposed may be immunized as well.
• BCG also has some effectiveness against Buruli ulcer infection and other nontuberculous mycobacteria infections.
• Additionally it is sometimes used as part of the treatment of bladder cancer.
• India and Pakistan introduced BCG mass immunization in 1948, the first countries outside Europe to do so.
• Several studies have shown that the BCG vaccine, because it accentuates a powerful immune response, has conferred a significant degree of protection against leprosy and non-invasive bladder cancers.
• The BCG vaccine is known to confer a strong immune response and a significant degree of protection against leprosy and non-invasive bladder cancers.
• Those countries where the elderly were likely to have had a BCG shot in their childhood were likely to be better protected against coronavirus because COVID-19 was particularly lethal to the elderly.