Understanding the Molecular Biology of SARS-CoV-2 and the COVID-19 Pandemic: A Review

Coronaviruses are named after the crown-like spike proteins on their surface. In the 21st century, three coronaviruses, namely severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), SARS-CoV, and Middle East respiratory syndrome related coronavirus (MERS-CoV), have emerged in the human population, presumably evolving from pathogens infecting other animals. Coronaviruses are enveloped viruses responsible for 15-30% of the atypical pneumonia cases in humans worldwide. The current coronavirus disease 2019 (COVID-19) pandemic is caused by the newest SARS virus, SARS-CoV-2, an enveloped, positive-sense, single-stranded RNA betacoronavirus of the family Coronaviridae. As of April 2021, the World Health Organization has reported more than 3 million deaths from COVID-19 and more than 140 million people have been infected with the virus, thereby making it the worst SARS pandemic of all time. Here, I review the current understanding of the molecular biology of coronaviruses and their host interactions, bringing together knowledge of the infection process to aid in the development of therapeutic drugs and/or vaccines against SARS-CoV-2. I also briefly overview the current situation of available treatments, vaccinations, and emerging strains.