With COVAXIN by Bharat Biotech getting regulatory nod for human trials, there has been an expectation of a Corona vaccine emerging from India.
Worldwide, there have been 140 candidates for developing vaccine, and among them 11 have entered the phase of human trial. COVAXIN by Bharat Biotech is one among those 11.
Vaccine in Simple Terms
A vaccine is a method to artificially induce the immunological memory. Once the antigens of the nasty pathogen are introduced, the immune system is triggered into developing pairing antibodies and immunological memory.
How COVAXIN by Bharat Biotech Expected to Work
The Bharat Biotech’s COVAXIN uses the virus isolated from an Indian patient by the National Institute of Virology (NIV) Pune to develop the inactivated virus vaccine.
Novel coronavirus infects the human cells with the help of its spike proteins. The spike protein of the virus binds with the ACE2 receptors on the surface of the human respiratory tract cells. Once the virus fuses, the viral genome is slipped into the human cell where around a thousand copies of the virus are made in just ten hours. These baby viruses emigrate to nearby cells.
Infection can be arrested if only we can deactivate the spike protein of the novel coronavirus. Thus, the antigen on the spike protein is a crucial vaccine target. If the antibody blocks the spike protein, then the virus cannot bind the cell and multiply.
The genomic code of the spike protein is spliced into a harmless DNA plasmid. This modified plasmid DNA with the genetic code of viral spike protein is introduced into the host cells. The cellular machinery translates the DNA and produces the viral protein encoded in the genome. The human immune system recognises the alien protein and develops a matching antibody.
After this vaccination, if at any time, people are infected by the novel coronavirus, then sensing the spike protein antibodies are released instantly. The immune killer cells seize deactivated viruses. Contagion is arrested even before infection sets in.
The Vaccine Race
Over seven vaccines are currently being researched in India with two receiving the nod for human trials. ZyCov-D Vaccine by Zydus Cadila is another Indian candidate.
Indian manufacturers account for 60% of vaccine supplies to UNICEF. The vaccine for novel coronavirus may be developed anywhere in the world, but without Indian manufacturers’ involvement, the production of required quantity is not going to be feasible.