Table 1.

A Summary of the Key Features of Influenza and SARS-CoV-2

	Influenza	SARS-CoV-2
Disease	Influenza infection	COVID-19
Structure (45,133)	Segmented, negative-stranded RNA viruses; the envelope of influenza A is formed by HA, NA, M1, and M2 proteins, whereas influenza B is formed by NA, HA, NB, and BM2 proteins.	Positive, single-stranded RNA virus with glycoprotein spikes in the shape of a crown present in its envelope.
Global R0 (133,134)	1.3	2.2
Case fatality rate (133,135,136)	0.2%	1%–2%
Transmission	Respiratory droplets
Incubation time (133,137)	2–4 days	3–7 days
Diagnosis (133,137)	Molecular test, serology, imaging
Cardiovascular complications	Proinflammatory and prothrombotic effects that increase the risks of acute MI and heart failure. Patients with known CVD who get infected with influenza could also present with fever, tachycardia, potential volume overload, and arrhythmia.	Proinflammatory and prothrombotic effects leading to acute MI or myocardial injury and heart failure, disseminated thrombosis, hypotension, arrhythmia, sudden cardiac death, and pediatric inflammatory multisystem syndrome.

BM2 = influenza B matrix ion channel 2; CVD = cardiovascular disease; HA = hemagglutinin; M1 = matrix ion channel 1; MI = myocardial infarction; NA = neuraminidase; NB = type III integral membrane protein; R0 = basic reproduction number; RNA = ribonucleic acid; SARS-CoV-2 = severe acute respiratory syndrome coronavirus-2.