Table.

Virological assessment results for SARS-CoV-2 at baseline and day 8 after the event

	Control group (n=495)	Experimental group (n=465)
Baseline screening
Ag-RDT positive	0	0
TMA positive*	15 (3·0%)	13 (3%)
Cell culture positive	0	0
RT-PCR positive	1 (<1%)	1 (<1%)
Ct value	37	37
Follow-up assessment
Ag-RDT positive	2 (0·4%)	0
TMA positive†	15 (3·0%)	12 (3%)
TMA positive at baseline	4	3
TMA negative at baseline	11	9
RT-PCR positive	2 (0·4%)	0
Ct value	26·3; 28·3	NA
Infected with SARS-CoV-2	2 (0·4%)	0

Ag-RDT=antigen-detecting rapid diagnostic tests. TMA=transcription-mediated amplification test. RT-PCR=real-time reverse transcriptase-polymerase chain reaction. Ct=cycle threshold. NA=not applicable.

^*Three TMA results in the control group were inconclusive.

^†One TMA result in the experimental group was inconclusive.