Table 3. Quantitative SARS-CoV-2 spike 1–2 IgG antibody titers against SARS-CoV-2 in participants with a positive or negative history of SARS-CoV-2 infection.

History of SARS-CoV-2 (n = 168) AU/ml	21–28 days after first BNT dose (S1) (IQR)	21–28 days after second BNT dose (S2) (IQR)	Three months after the second BNT dose (S3) (IQR)	1–7 days after the third BNT booster (S4) (IQR)	21–28 days after the third BNT booster (S5) (IQR)
Negative (n = 95)	103 (77.6)	1350 (1224.0)	205 (149.0)	379 (645.5)	2960 (2010.0)
Positive (n = 73)	1130 (4756.0)	2390 (2540.0)	377 (1144.7)	590 (1262.0)	3090 (2080.0)
p-value	<0.001	0.002	0.001	0.011	0.377

Data are presented as medians and interquartile ranges. The participants were divided into two groups, those with a negative and a positive history of SARS-CoV-2 infection.