A review SARS-CoV-2 the other face to SARS-CoV and MERS-CoV: About future predictions

Abstract COVID-19 outbreak is proving to be an unprecedented disaster that lays its dark shadow on global health, economics and personal freedom. SARS and MERS epidemics provide scientific data that is useful in better understanding and resolution of COVID 19. Similarities among SARS-CoV, MERS-CoV and SARS-CoV-2 have been investigated in the light of available data. SARS-CoV, MERS-CoV and SARS-CoV-2 evolved in bats and have positive-sense RNA genomes of 27.9kb, 30.1kb and 29.9kb, respectively. Molecular and serological tools used for diagnosis of SARS and MERS patients resemble COVID-19 diagnostic tools. Stability and longevity data of SARS and MERS epidemics contribute in the current pandemic precaution policies. Trials to produce vaccines for SARS-CoV and MERS-CoV failed, therefore the current review predict that trials for SARS-CoV-2 vaccine production if achieved, will be require more time not only for vaccine production but also to be available for patients, during this time antiviral agents, Convalescent plasma and monoclonal antibodies provide potential tratments for sever patients. The mortality rate caused by the SARS-CoV and MERS-CoV reached 15% and 37%, respectively. The first declarations about mortality rate of SARS-CoV-2 was around 2-4% but now this rate differs globally and reached more than 13% in some countries. A realistic COVID-19 outbreak scenario suggest that the pandemic might last for three years with fluctuation in the number of infected cases, unless a vaccine or antiviral drug is to be discovered.