Table 1.

Characterizations of animal models for COVID-19.

Animals/Design	Challenge Dose	Route	Lethality	Clinical Features	Infected Organs	References
hACE2 transgenic C3B6 mice	3 × 104 TCID50	i.n.	No	Interstitial pneumonia and pathology, weight loss	Lungs, eye, heart, and brain	[11]
hACE2 transgenic C57BL/6 mice	4 × 105 PFU 40 μL, 107 PFU/mL	i.n./i.g. i.t.	No No	Interstitial pneumonia, pathology, and elevated cytokines ARDS, lung pathology, neutrophilic infiltration	Lung, trachea, and brain	[12,13] [14]
hACE2-transduced BALB/c and C57BL/6 mice	105 PFU	i.n. + i.t.	No	Pneumonia, lung pathology, and weight loss	Lung, heart, spleen, and brain	[15,16]
BALB/c or C57BL/6 mouse-adapted SARS-CoV-2	7.2 × 105 PFU 106.2 PFU/104.4 PFU 102~105 PFU	i.n. i.n. i.n.	No No Yes	Moderate pneumonia and inflammatory responses / ALI, lung disease, elevated cytokines	Lung, upper and lower respiratory tract	[17] [18] [19]
Golden hamsters	8 × 104 TCID50/105 PFU	i.n.	No	Lung pathology, weight loss, rapid breathing	URT, duodenum epithelial cells, and lung consolidation areas	[20,21,22,24,25,26,27,64]
Ferrets	105.5 TCID50	i.n.	No	Elevated body temperature, acute bronchiolitis	Nasal turbinate, trachea, lungs, and intestine	[28,29]
Rhesus macaques	106 TCID50	i.n.	No	Interstitial pneumonia and pathology, weight loss, asthenia, respiratory disease	Nose, throat, lung, and anus	[40,41,42,43,44,45,46,47,48,49,50]
Cynomolgus macaques	/	i.n. + i.t.	No	Lung pathology, no overt clinical signs	Nose, throat trachea, bronchi, and lung lobes	[51,52,53]

Note: TCID₅₀: median tissue culture infective dose; i.n.: Intranasal inoculation; i.g.: Intragastric inoculation; i.t.: Intratracheal inoculation.