Table 1.

Characteristics of the studies and participants.

ID	First author (reference)	Type of study	Publication year	Country	Study population	Age	Gender (%)	Sign and symptoms	Laboratory data
1	Bao et al. 14	Experimental (animal study)	2020	China	34 transgenic mice	6–11 months old	Male/female	Weight loss, interstitial pneumonia, and virus replication in the lungs	N/A
2	Bao et al. 15	Experimental (animal study)	2020	China	23 transgenic mice	4–6 months old	Male/female	Weight loss	Based on serological analyses, 10 out of 23 mice were infected after direct contact and respiratory droplets exposure
3	Basu 16	Cross-sectional	2021	USA	2 SARS-CoV-2 positive	49 (37 and 61 years old)	Female (100)	N/A	N/A
4	Bullard et al. 17	Cross-sectional	2021	Canada	90 SARS-CoV-2-positive samples	45	Male (49) Female (51)	N/A	N/A
5	Bullard et al. 18	Case series	2021	Canada	305 COVID-19 patients (97 children aged ⩽ 10 years, 78 children aged 11-17 years, 130 adults)	N/A	N/A	N/A	Culture growth in 31% of samples was seen; 19% in young children, 23% in older children, and 44% in adults
6	Chan et al. 19	Case series	2020	China	273 Specimens from 15 SARS-CoV-2-positive patients	N/A	N/A	N/A	28.2% were COVID-19-RdRp/Hel and RdRp-P2 positive. All of them were positive for COVID-19-RdRp/Hel assay
7	Cross et al. 20	Experimental (animal study)	2020	USA	6 African green monkeys	N/A	N/A	Declined appetite, increased temperature, hypercapnia (3/6), gas distinction of small intestines. All monkeys had pulmonary consolidation with hyperemia and hemorrhage. Three of them had multifocal neutrophilicbroncho-interstitial pneumonia	Lymphocytopenia (5/6), thrombocytopenia (3/6 animals), granulocytosis (6/6), mild increase in ALT (2/6), a moderate increase in CRP (5/6), prolonged aPTT (6/6). SARS-CoV-2 vRNA was detected in the nasal swabs of all animals
8	Deng et al. 21	Experimental (animal study)	2020	China	5 Rhesus macaques	3-5 years old	Male (100)	Opaque glass signs, obscure lung marking, severe progressive pulmonary infiltration, patchy lesions, increased density, and interstitial pneumonia appeared in the lungs	Viral load detected in nasal and throat swabs of CJ- and IT-inoculated animals from 1 to 6 days’ post-inoculation. Only in CJ-inoculated animals, viral load detected in conjunctival swabs and only in IT-inoculated animals is viral load detected in anal swabs
9	Dhakal et al. 22	Experimental (animal study)	2021	USA	Golden Syrian hamsters	8–10 week	Male/female	Bodyweight loss, lung injury	Females had two-fold greater IgM, IgG, and IgA responses and significantly greater IgG antibodies against the virus
10	Johnston et al. 23	Experimental (animal study)	2021	USA	3 naïve African green monkeys 4rhesus Macaques 4cynomolgus macaques	N/A	N/A	Fever, lung opacity, mild hypoxia and erythema around the eyes, rectal bleeding	Lymphocyte and neutrophil fluctuations were noted for most animals on the study and were likely a result of the inflammatory response to infection
11	Kumar et al. 24	Experimental (animal study)	2021	USA	Male Syrian golden hamsters	N/A	N/A	N/A	N/A
12	Rathnasinghe et al. 25	Experimental (animal study)	2020	USA	2 hACE2 mice	6 weeks old	Female (100)	In K18-hACE2 mice: 75% body weight loss, lethargy, ruffled fur, hunched posture, and labored breathing	Rathnasinghe et al. 25 In K18-hACE2 mice: viral replication in the spleen and the lungs. Viral titers in the lung were 2–3 log higher than Ad-HaCE2 mice
13	Rosenke et al. 26	Experimental (animal study)	2020	USA	24 Syrian hamsters	4–6 weeks old and >27 weeks old	Male/female	Moderate broncho-interstitial pneumonia, along with high viral load in lungs and extensive virus shedding. Minor changes in respiratory pattern, lung lesions, loss of <10% body weight	In oral and rectal swabs high levels of viral gRNA were detected. On day 11 after infection, all oral swabs were positive and suggested that viral replication in upper respiratory areas was still ongoing
14	Ryan et al. 27	Experimental (animal study)	2021	UK	18 ferrets (three groups, every 6 ferrets)	N/A	Male/Female	In all ferrets of medium and high group: mild multifocal bronchopneumonia	In all ferrets of the medium and high group and one ferret of low group: Viral RNA shedding in the upper respiratory tract
15	Sia et al. 28	Experimental (animal study)	2020	China	Golden hamsters	4–5 weeks	Male (100)	Pneumocyte hyperplasia and weight loss	N/A
16	Song et al. 29	Experimental (animal study)	2021	China	18 hamsters	12 weeks	Male/female	N/A	N/A
17	Van der Moeren et al. 30	Cross-sectional	2021	Netherland	248 (74 qRT-PCR positives, 174 qRT-PCR negatives) clinical combined oro-nasopharyngeal samples of individuals with COVID-19-like symptoms	N/A	N/A	Rhinitis, cough, elevated temperature, shortness of breath, or sudden loss of sense of taste or smell	DAA result: positive = 54 (Ct-value 12.2–27.7), negative = 20 (Ct-value 22.6–39.5)
18	Woolsey et al. 31	Experimental (animal study)	2020	USA	6 adult African green monkeys	N/A	N/A	Decreased appetite, fever, and hyperemia multifocal lesions of each lobe. The small intestine was somewhat loose and dilated with gas and yellow fluid. Mild lymphoid enlargement. Pulmonary edema and pulmonary hemorrhage. Pneumonia.	N/A
19	Yamayoshi et al. 32	Case series	2020	Japan	SARS-CoV-2-positive samples	N/A	N/A	N/A	N/A

SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; COVID-19: coronavirus disease 2019; qRT-PCR: quantitative real-time polymerase chain reaction; ALT: alanine aminotransferase; CRP: C-reactive protein; aPTT: activated partial thromboplastin time; CJ: conjunctivally; IT: intratracheally.