Table 1.

Basic Characteristics of four passages patients

		Numbers (%)
		Passage 1 (n = 1)	Passage 2 (n = 8)	Passage 3 (n = 23)	Passage 4 (n = 46)	p values
Age	Median	48.00	51.50	48.00	44.00	0.19
Gender
Female		0	4 (50.00)	10 (43.48)	20 (43.47)	0.40
Male		1	4 (50.00)	13 (56.52)	26 (56.53)
Symptoms
Fever		1	7 (87.50)	16 (69.57)	26 (56.52)	0.19
Cough		1	8 (100.00)	18 (78.26)	38 (82.61)	0.36
Fatigue		1	8 (100.00)	23 (100.00)	44 (95.65)	0.50
Headache		0	1 (12.50)	2 (8.70)	1 (2.17)	0.32
Anorexia		0	1 (12.50)	4 (17.39)	12 (26.08)	0.56
Diarrhear		0	0 (0.00)	0 (0.00)	0 (0.00)
Nasal congestion		0	0 (0.00)	1 (4.35)	0 (0.00)	0.30
Pharyngalgia		1	4 (50.00)	10 (43.48)	7 (15.22)	0.01
Lymphadenopathy		0	0 (0.00)	0 (0.00)	0 (0.00)
Myalgia		1	1 (12.50)	1 (4.35)	7 (15.22)	0.41
Dyspnea		0	2 (25.00)	1 (4.35)	0 (0.00)	0.003
Vomit		0	0 (0.00)	1 (4.35)	1 (2.17)	0.77
Abdomin pain		0	1 (12.50)	1 (4.35)	0 (0.00)	0.10
Comorbidities
Hypertension		0	4 (50.00)	6 (26.09)	9 (19.57)	0.18
Diabetes		0	4 (25.00)	3 (0.00)	1 (0.00)	< 0.001
Tuberculosis		0	3 (37.50)	1 (4.35)	3 (6.52)	0.01
Hepatitis B		0	0 (0.00)	1 (4.35)	2 (4.35)	0.83
Cardiovascular disease		0	0 (0.00)	1 (4.35)	0 (0.00)	0.30
COPD		0	1 (12.50)	0 (0.00)	0 (0.00)	0.01
Malignancy		0	0 (0.00)	0 (0.00)	0 (0.00)
Chronic kidney Disease		0	0 (0.00)	0 (0.00)	0 (0.00)
Chronic liver disease		0	0 (0.00)	0 (0.00)	0 (0.00)
HIV		0	0 (0.00)	0 (0.00)	0 (0.00)
Medium incubation days		9.00	7.00 (2–12)	8.00 (4–13)	10.00 (7–15)	0.005

P values indicate differences among Passage 2, Passage 3 and Passage 4 patients. P < 0.05 was considered statistically significant. The comparisons of the clinical characteristics, excluding age and incubation days, were performed by χ2 test. ^a The comparison of age and the comparison of incubation days among different groups was performed by one-way ANOVA with Bonferroni’s post-test