Table 1.

Sampling time points in relation to patient illness and results of clinical samples

Room	Patient	On the day of environment sampling				Most recent clinical samples (Ct values, ORF1ab/N genes)b
		Days of illness or positive PCRa	Symptoms	Nebuli- zation	Positive clinical samples (Ct values, ORF1ab/N genes)c
1	A	33	None	+	All negative	Nasopharyngeal swab (36.5/27.7), day 31
2	B	34	Breath shortness, chest pain		All negative	Nasopharyngeal swab (36.5/19.4) & sputum (36.7/26), day 32
3	C	42	Cough	+	Nasopharyngeal swab (32.3/35.8)
		50	Cough, fever		Nasopharyngeal swab (-/35.5) & sputum (21.4/24.9)
4	D	39	Cough, sputum production, fever	+	All negative	Nasopharyngeal swab (28/29.3), day 37
		47	Cough, sputum production	+	Nasopharyngeal swab (-/37.3)
	E	40	None		All negative	Oropharyngeal swab (25.1/23.5), day 38
5	F	44	Cough, sputum production	+	Sputum (28.0/20.8)
		52	Cough, sputum production		Oropharyngeal swab (-/34.2) & sputum (23.4/25.1)
	G	33	None		Nasopharyngeal swab (37.3/34.7)
6	H	34	Cough, sputum production		Sputum (37.1/32.8)
		42	Cough, sputum production		Nasopharyngeal swab (28.0/28.3)
	I	35	None		Stool (37.9/26.0)
		43	Palpitation, chest burning sensation	+	Nasopharyngeal (-/36.1) & oropharyngeal swabs (28.2/25.3)

^aFor those without symptoms, the days refer to the positive PCR status

^bOn the day of environment sampling, nasopharyngeal swab, oropharyngeal swab, sputum and stool were collected for all patients with symptoms, while nasopharyngeal swab, oropharyngeal swab and stool were collected for all patients without symptoms. Cycle threshold (Ct) values of PCR were shown. -, negative at the 40th cycles

^cThe most recent positive clinical samples are shown for patients with no positive clinical samples on the day of environment sampling