ABSTRACT
Seven human coronaviruses have been identified at the time of writing. Three of them, including SARS-CoV-2, have caused outbreaks, which unfortunately is likely to happen again in the future. The ongoing COVID-19 pandemic caused by SARS-CoV-2 has been around for more than a year now, and has caused unprecedented damage to human lives and the global economy. While some light can be seen at the end of the tunnel, the pandemic is far from over. Recently, several variants of concern have appeared, reducing to some extent the efforts of national lockdowns and mass vaccination. Now several countries which showed an encouraging trend of reduced cases of COVID-19 are experiencing a second wave of the pandemic. Before the SARS, MERS and COVID-19 outbreaks, coronavirus infections were thought to be similar to common cold and flu infections, which after seasonal appearances would eventually run its course and disappear. In contrast, the current pandemic has claimed millions of human lives and the end of the pandemic is unclear. The fear over increased transmissibility and mortality because of the high rate of mutation in the RNA genome of SARS-CoV-2 is of concern and discussed in this chapter. An update on the epidemiology of the current pandemic and previous coronavirus outbreaks are discussed. Further, we have introduced the proteome of all identified human coronaviruses and presented in detail potential therapeutic targets for SARS-CoV and SARS-CoV-2.
