What is the biology of SARS-CoV-2?

Coronaviruses are enveloped, positive-sense single-stranded RNA viruses with a nucleocapsid of helical symmetry (protein coat) (Zulma et al., 2016). Coronaviruses are members of the subfamily “Coronavirinae” (family; Coronaviridae, 62 order; Nidovirales) that contains four genera. Alpha and beta coronaviruses are known to harm humans and animals (Khan et al., 2020). Gamma and delta coronaviruses generally infect birds, although some of them can cause infection in mammals. For human health, beta-coronaviruses are the most important group as this group contains the highly pathogenic viruses in humans including SARS-CoV-2, MERS-CoV and SARS- CoV (Cui et al., 2019; Su et al., 2016; Forni et al., 2017).