Remember BCG? It may be India’s weapon against coronavirus, says US study
Srinagar, Mar 31: Remember the BCG shots we all have received in our childhood! Well, according to a March 28 study, the countries with universal policies of BCG vaccination including India could have better chances against coronavirus than those that did not have such a policy in place.
The findings published by NYIT College of Osteopathic
Medicine (NYITCOM), researchers, led by Gonzalo Otazu, Ph.D., assistant
professor of biomedical sciences reveal the Bacillus Calmette-Guerin (BCG) vaccine,
also known as tuberculosis (TB) vaccine, could be a potential weapon in
combatting the deadly coronavirus.
“We found that 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,” the researchers said in an official statement on Monday.
According to the study accessed by The Kashmir Monitor, the
vaccination is believed to offer broad-ranging protection against respiratory
infections, which present similar symptoms to COVID-19.
“The broad use of the BCG vaccine across a population could
reduce the number of carriers, and combined with other measures could act to
slow down or stop the spread of COVID-19,” the study says.
As one of the most widely used vaccines in the world, the
BCG vaccine has existed for nearly a century and has been shown to be an
effective tool in preventing meningitis and disseminated TB in children.
“Several vaccines including the BCG vaccination have been
shown to produce positive ‘heterologous’ or non-specific immune effects leading
to improved response against other nonmycobacterial pathogens…This phenomenon
was named ‘trained immunity’ and is proposed to be caused by metabolic and
epigenetic changes leading to promotion of genetic regions encoding for
pro-inflammatory cytokines…,” it reads.
Dr Otazu, who is also a researcher in the new Center for
Biomedical Innovation, completed the study with the assistance of NYITCOM
students Aaron Miller, Mac Josh Reandelar, Kimberly Fasciglione, and Violeta
Roumenova, along with Center technician Yan Li.
The team compared various nations’ BCG vaccination policies
with their COVID-19 morbidity and mortality and found a significant positive
correlation between the year when universal BCG vaccination policies were
adopted and the country’s mortality rate.
In other words, the earlier a policy was established, the
more likely that a significant portion of the population, especially the
elderly, would be protected.
“For example Iran, which has a current universal BCG
vaccination policy that only started in 1984, has an elevated mortality rate
with 19.7 deaths per million inhabitants. In contrast, Japan, which started its
universal BCG policy in 1947, has approximately 100 times fewer deaths per
million people, with 0.28 deaths. Furthermore, Brazil started universal
vaccination in 1920 and has an even lower mortality rate of 0.0573 deaths per
million inhabitants,” the study reads.
India started BCG vaccination of children in 1949, and
currently 97% of 26 million children born in India receive the BCG vaccine
free. India’s universal immunisation programme, under which the BCG vaccine is
given, went up to the current figure of 97%, according to the ministry of
health and family welfare data.
The vaccine is manufactured in India, and costs less than Rs
100 per vial in the private sector.
“We found that countries without universal policies of BCG
vaccination (Italy, Nederland, USA) have been more severely affected compared
to countries with universal and long-standing BCG policies,” the study says.
It also answers why Covid-19 spread in China despite
children getting BCG vaccinated since the 1950s.
“During the Cultural
Revolution (1966-1976), tuberculosis prevention and treatment agencies were
disbanded and weakened. We speculate that this could have created a pool of
potential hosts that would be affected by and spread Covid-19,” said the study.
So why do some nations vaccinate while others do not?
As TB cases fell in the late 20th century, several
higher-income countries in Europe dropped their universal BCG policies between
1963 and 2010. In the United States, the CDC currently recommends the BCG
vaccine only for very select persons who meet specific criteria and in
consultation with a TB expert.
Among the 180 countries with BCG data available today, 157
countries currently recommend universal BCG vaccination. The remaining 23
countries have either stopped BCG vaccination due to a reduction in TB
incidence or have traditionally favoured selective vaccination of “at-risk”
Methods and results
The team collected the BCG vaccination policies across
countries from the BCG World Atlas 6 and complemented the database in respect
to dates of initiation of BCG vaccination. Data of COVID-19 cases and death per
country were obtained from Google crisis response map as latest as till March
The countries were divided in three categories: low income
(L) with an annual income of 1,025 dollars or less, lower middle income with an
income between 1,026 and 3,995 dollars, and middle high and high income
countries, which included countries with annual incomes over 3,996 dollars.
“In order to determine if BCG vaccination was protective for
COVID-19 infections, we used the number of deaths per million inhabitants per
country attributed to COVID-19. Most of the countries with low-income levels
(17/18) reported zero deaths attributed to COVID-19 and have universal BCG
policies in place consistent with a protective role of BCG vaccination,” the
It added that middle high and high- income countries that
have a current universal BCG policy (55 countries) had 0.78± 0.40 deaths per
“In contrast, middle high and high income countries that
never had a universal BCG policy (5 countries) had a larger mortality rate,
with 16.39 ± 7.33 deaths per million people. This difference between countries
was highly significant,” it stated.
Corroborating the study, Australia, Netherlands, Germany and
the United Kingdom have announced they will begin large-scale human trials to
see whether BCG vaccination protects health workers from Covid-19 by triggering
an immune response to reduce symptoms, prevent severe illness or prevent
Australia announced on Friday that it will begin BCG vaccine
trials with around 4,000 physicians and nurses, who are at higher risk of
becoming infected with the respiratory disease than the general population, and
in older persons, who are at higher risk of serious illness.
Netherlands has recruited around 1,000 healthcare workers in
eight Dutch hospitals to either receive the BCG vaccine or a placebo.