9. Conclusions
Because of structural similarity and binding to same host cell
receptors, SARS-CoV-2 and SARS-CoV may potentially share similar disease
pathogenesis and exhibit cross-immunity to some extent. The
understanding of biological characteristics of SARS-CoV and
technological advancement in vaccine production could make
first-generation COVID-19 vaccine available very soon, though it may not
be available to cater the current pandemic. There are about 7 or 8
SARS-CoV-2 antigenic candidates which could be employed for vaccine
development. But there is a need of vigorous testing for immunogenicity,
safety, efficacy, and level of protection conferred in the hosts.
Hastening the deployment of first-generation vaccine for current
pandemic could be achieved by propelling the nucleic acid based priming
vaccines followed by boosters of protein based vaccines to curtail the
mortality in high risk groups such as elderly persons and health care
workers. Parallel to this, more potent and efficient second-generation
vaccine production for future should be carried out to prevent disease
spread, mortalities, and viral shedding. Another intriguing aspect of
CoVs is that in every decade of 21st century there is
a new major CoV epidemic viz . SARS in 2002, MERS in 2012, and now
COVID-19. Such epidemics are expected in future too. Among CoVs S2
subunit is highly conserved and homologous which is a potential target
for development of a pan-CoV vaccines after enhancing its immunogenicity
and it can be used across all population worldwide and against divergent
strains of CoVs. Thus, there is a need to mobilize the international
funding agencies to support the development, manufacture, and
stockpiling of CoV vaccines.