Abstract:
COVID‑19 pandemic caused by SARS-CoV-2 created a bio threat
situation throughout the world. This article features evolution and clinical outcomes of
SARS-CoV-2, SARS-CoV-1 and MERS-CoV. COVID‑19 originated in Wuhan,
China and resulted in severe morbidity and mortality. Features of SARS are similar
to COVID‑19. MERS exhibited a relatively milder disease, mainly in Middle East
countries. Coronaviruses are large (100 nm) viruses exhibiting a spherical shape with a
lipoprotein envelope and can cause diseases in animals and humans. All coronaviruses
are sensitive to physicochemical agents. They attach to angiotensin Converting Enzyme
-2 (ACE-2) and serine protease receptors of lungs. Literature review and genetic homology
were conducted using data sources and bioinformatics tools for the comparison of SARSCoV-
2 with SARS-CoV-1 and MERS-CoV. Genome analysis between SARS-CoV-2
with SARS-CoV-1 and MERS-CoV revealed that SARS-CoV-2 and SARS-CoV-1 are
95% related with each other whereas SARS-CoV-2 and MERS-CoV are 65% related.
SARS-CoV-2 and SARS-CoV-1 are genetically more related than MERS-CoV. Animal
reservoirs for SARS-CoV-2 and SARS-CoV-1 may be bats, pangolins, etc. MERS can be
transmitted from infected camels. SARS-CoV-2 might have evolved from SARS-CoV-1
or from another animal reservoir coronavirus. It can be transmitted from infected animals
and humans through respiratory route. Strict public health measures such as physical
distancing and maintaining good hygiene should be taken to contain their community
spread. SARS-CoV-2 can undergo antigenic variation resulting in difficulty to develop
drugs and vaccines. COVID‑19 has caused a severe blow to the economy of both developed
and developing nations.
