Virus load and virus shedding of SARS-CoV-2 and their impact on patient outcomes

Table 1 Characteristics and outcomes of the patients

		All	Viral shedding (d)		P value
			< 14	≥ 14
	Total	145	53 (37%)	92 (63%)
Demographics	Age, yr	46.1 (42.6-49.9)	39.6 (34.2-45.9)	50.3 (46.1-54.9)	0.004
	Sex, male, n (%)	79 (54.5%)	25 (47.2%)	54 (58.7%)	0.18
	BMI (kg/m2)	23.6 (22.9-24.2)	22.9 (21.9-24.1)	23.9 (23.2-24.7)	0.131
	History of Hubei contact	129 (89.0%)	50 (94.3%)	79 (85.9%)	0.117
	Smoking	3 (2.1%)	0	3 (3.3%)	0.184
	Symptom to admission (d)	4.6 (4.1-5.1)	4.4 (3.6-5.3)	4.7 (4.1-5.3)	0.553
	Symptom to ICU (d)	12.0 (10.8-13.4)	10.5 (8.7-12.7)	12.4 (10.9-14.2)	0.236
Comorbidities	Hypertension	26 (17.9%)	5 (9.4%)	21 (22.8%)	0.043
	Diabetes	11 (7.6%)	4 (7.6%)	7 (7.6%)	0.989
	Heart disease	18 (12.4%)	3 (5.7%)	15 (16.3%)	0.061
	COPD	4 (2.8%)	1 (1.9%)	3 (3.3%)	0.627
Laboratory findings on admission	Temperature (°C)	37.4 (37.3-37.5)	37.3 (37.0-37.5)	37.5 (37.3-37.6)	0.256
	WBC (× 109/L)	4.84 (4.58-5.12)	4.89 (4.46-5.36)	4.82 (4.49-5.16)	0.784
	PLT (× 1012/L)	175.51 (166.47-185.05)	201.84 (185.82-219.25)	161.75 (151.91-172.23)	< 0.001
	LYMPH (× 109/L)	1.20 (1.10-1.29)	1.21 (1.06-1.37)	1.19 (1.07-1.31)	0.839
	IL-6 (ug/L)	18.24 (14.93-22.29)	12.55 (8.58-18.36)	21.72 (17.34-27.20)	0.012
	CR (mg/L)	67.47 (64.12-71.00)	62.03 (57.87-66.50)	70.87 (66.21-75.86)	0.013
	Viral load in respiratory tract [log (copies)]	3.69 (3.06-5.07)	3.36 (2.49-4.83)	4.22 (3.10-5.12)	0.192
	PAO2/FIO2				0.897
	< 100	1 (0.7%)	0	1 (1.1%)
	≥ 100, < 200	8 (5.9%)	3 (6.4%)	5 (5.7%)
	≥ 200, < 300	19 (14.1%)	7 (14.9%)	12 (13.6%)
	≥ 300	107 (79.3%)	37 (78.7%)	70 (79.6%)
Severity score	APACHEII	4.2 (3.7-4.7)	3.4 (2.8-4.1)	4.8 (4.2-5.5)	0.003
	SOFA	1.7 (1.5-1.9)	1.4 (1.2-1.7)	1.9 (1.6-2.2)	0.027
	GCS	14.8 (14.5-15.2)	15.0 (15.0-15.0)	14.7 (14.2-15.3)	0.45
Symptoms	Fever	123 (84.8%)	41 (77.4%)	82 (89.1%)	0.057
	Sore muscles	32 (22.1%)	13 (24.5%)	19 (20.7%)	0.588
	Cough	84 (57.9%)	31 (58.5%)	53 (57.6%)	0.917
	ARV in the first 3 d	0.008
	None				16 (11.0%) 10 (18.9%)
	Kaletra	40 (27.6%)	8 (15.1%)	32 (34.8%)
	Kaletra & Other ARV	40 (27.6%)	19 (35.9%)	21 (22.8%)
	Other ARV but Kaletra	49 (33.8%)	16 (30.2%)	33 (35.9%)
	ARV in the first 3 d				0.014
	0	16 (11.0%)	10 (18.9%)	6 (6.5%)
	1	84 (57.9%)	22 (41.5%)	62 (67.4%)
	2	38 (26.2%)	18 (34.0%)	20 (21.7%)
	3	7 (4.8%)	3 (5.7%)	4 (4.4%)
	Globulin	61 (42.1%)	12 (22.6%)	49 (53.3%)	< 0.001
	Steroid	57 (39.3%)	12 (22.6%)	45 (48.9%)	0.002
	Thymosin alpha-1	59 (40.7%)	13 (24.5%)	46 (50.0%)	0.003
	Antibiotics	50 (34.5%)	15 (28.3%)	35 (38.0%)	0.235
	Other treatments	11 (7.6%)	0	11 (12.0%)	0.009
	HFO	18 (12.4%)	7 (13.2%)	11 (12.0%)	0.826
	MV	16 (11.0%)	1 (1.9%)	15 (16.3%)	0.008
	NMV	46 (31.7%)	11 (20.8%)	35 (38.0%)	0.031
	CRRT	4 (2.8%)	0	4 (4.4%)	0.124
Outcome	Negative	108 (74.5%)	53 (100%)	55 (59.8%)	< 0.001
	Viral shedding (d)	17.3 (15.8-18.9)	12.1 (11.0-13.3)	24.4 (22.6-26.3)	< 0.001
	Length of ICU stay (d)	13.6 (9.4-19.8)	7.0 (3.7-13.1)	16.3 (10.7-24.9)	0.067
	Length of hospital stay (d)	25 (23-28)	21 (18-24)	28 (25-32)	0.002
	Death	3 (2.1%)	0	3 (3.3%)	0.184
	Discharge	57 (39.3%)	29 (54.7%)	28 (30.4%)	0.004

Continuous variables were described by mean values with 95% confidence intervals, while categorical variables were presented using percentages. BMI: Body mass index; ICU: Intensive care unit; WBC: White blood count; PLT: Platelet; LYMPH: Lymphocyte; IL-6: Interleukin 6; CR: Serum creatinine; APACHEII: Acute Physiology And Chronic Health Evaluation II; SOFA: The Sequential Organ Failure Assessment; GCS: Glasgow Coma Scale; COPD: Chronic obstructive pulmonary disease; ARV: Antiretroviral therapy; HFO: High flow oxygen; MV: Mechanic ventilation; NMV: Non-invasive ventilation; CRRT: Continuous Renal Replacement Therapy.

Table 2 Univariate and multivariate regression analyses of the risk factors for viral shedding

Variables	Univariate		Multivariate
	HR (95%CI)	P value	HR (95%CI)	P value
Sex, male	1.1 (0.7, 1.6)	0.757	0.8 (0.5, 1.3)	0.422
Age (yr)
< 60	Reference
≥ 60	0.5 (0.4, 0.8)	0.002	0.6 (0.4, 1.0)	0.030
Diabetes	0.9 (0.5, 1.8)	0.870	1.4 (0.7, 2.7)	0.370
IVIG	0.5 (0.3, 0.7)	< 0.001	0.6 (0.3, 1.2)	0.182
Antibiotics	0.5 (0.4, 0.8)	0.002	0.7 (0.4, 1.3)	0.273
Steroids	0.5 (0.3, 0.7)	<0.001	0.8 (0.4, 1.7)	0.588
PAO2/FIO2
< 300	Reference
≥ 300	1.3 (0.8, 2.2)	0.247	1.0 (0.5, 1.7)	0.898
Chloroquine	26.8 (3.0, 239.3)	0.003	19.0 (1.9, 186.2)	0.012
NLR	1.0 (0.9, 1.0)	0.386	1.0 (1.0, 1.1)	0.632

IVIG: Intravenous immunoglobulin; NLR: Neutrophil-lymphocyte ratio.

Table 3 Impact of severe acute respiratory syndrome coronavirus 2 viral shedding on outcomes

	Non-adjusted		Model I		Model II
	HR (95%CI)	P value	HR (95%CI)	P value	HR (95%CI)	P value
ICU duration	0.52 (0.90-0.96)	0.02	0.49 (0.42-0.94)	0.03	0.48 (-0.01-0.97)	0.05
Hospital stay	0.15 (-0.01,0.32)	0.07	0.11 (-0.05-0.26)	0.18	0.11 (-0.05-0.26)	0.18
In-hospital mortality	1.07 (0.98, 1.17)	0.15	0.06 (-0.04-0.16)	0.23	0.06 (-0.04-0.16)	0.23

Data was presented as HR (95%CI) with P value for death and coefficient (95%CI), P value for intensive care unit length and hospital length. Model I, adjusted for age and sex; Model II, adjusted for age, sex, and body mass index. ICU: Intensive care unit.