Table 3.

SARS-CoV-2-specific antibody titers in relation to detectable SARS-CoV-2 RNA and infectious SARS-CoV-2 in nasopharynx in all COVID-19 patients (n = 36).

Total SARS- CoV-2 IgG titer	Number of patients	PCR Positive		PCR negative		Culture positive		Culture negative
		no.	%	no.	%	no.	%	no.	%
< 20	2	2	100	0	0	2	100	0	0
20 to 40	5	3	60	2	40	2	40	3	60
160 to 320	4	3	75	1	25	0	0	4	100
640 to 2560	25	6	24	19	76	0	0	25	100
Neutralizing antibody titer	Number of patients	PCR Positive		PCR negative		Culture positive		Culture negative
		no.	%	n	%	no.	%	no.	%
< 10	3	3	100	0	0	3	100	0	0
10 to 15	5	4	67	2	33	1a	17	5	83
30 to 120	18	7	41	10	59	0	0	17	100
160 to 580	10	0	0	10	100	0	0	10	100

^aneutralizing titer 10