The 2019 novel coronavirus (2019-nCoV) infection is an emerging pandemic that poses
a severe threat to global public health. This pandemic started from the Wuhan City of Hubei
Province in China, and is speculated to have originated from bats and spread among humans with
an unknown intermediate transmitter. The virus binds to angiotensin-converting enzyme 2 (ACE2),
which is abundantly expressed on various human cells, including lung epithelial and intestinal
cells, thereby entering into these cells and causing infection. It is transmitted to other humans
through airborne droplets from infected patients. Presently there are no specific treatments or
vaccines that are available to curtail the spread of this disease. There are few indirect reports that
explain the potential importance of the mandated BCG vaccine as a protective factor against
COVID-19. There is a speculation that a live attenuated vaccine (BCG vaccine) can be beneficial
against COVID-19 to develop the initial immune response, and can also spread in the community,
thereby boosting herd immunity to fight against COVID-19. This review summarizes the conclusions
of various reports on the BCG vaccine, and is an attempt to establish BCG-vaccination mediated
herd immunity as an effective instant intermediate approach in curbing COVID-19 spread in
highly populous countries.
