Table 1.

Characteristics of SARS-CoV-2

Particulars	Characteristics
Family	Coronaviridae
Sub family	Orthocoronavirinae
Order	Nidovirales
Genera	Four: αCoV, β-CoV, γ-CoV, and δ-CoV
RNA	Linear, single-stranded RNA genomes of positive polarity
Infection
α-CoV and β-CoV	Infect the respiratory, gastrointestinal, and CNS of humans and mammals
γ-CoV and δ-CoV	Infect the birds
β-CoV	SARS-CoV (2002–2003)
	MERS-CoV (2012)
	2019-nCoV (2019)
Nucleotide sequence similarity	79% with SARS-CoV and 50% with MERS-CoV
Natural host	Bat; 96.2% genome sequence similarity to RaTG13, a bat coronavirus detected in, Rhinolophus affinis
Intermediate hosts	Pangolins; 99% genome sequence similarity with pangolin-CoV
Protein structure	Spike protein (S-protein)
Receptor	Human angiotensin converting enzyme 2 (ACE2)
Binding affinity	High affinity between ACE2 and SARS-CoV-2 S protein Population with higher expression of ACE2 might be more susceptible to COVID-19