Table 2.

Seroconversion of IgG and/or IgM antibody against SARS-CoV-2 during follow-up time.

	Overall	Asymptomatic carrier (N = 15)	COVID-19 patients (N = 59)	P
Seroconversion of IgM antibody				0.647
From positive to negative	28 (37.8)	8 (53.3)	20 (33.9)	0.234
From positive to weak positive	9 (12.2)	1 (6.7)	8 (13.6)	0.676
Consistent negative	28 (37.8)	5 (33.3)	23 (39.0)	0.772
Consistent positive	9 (12.2)	1 (6.7)	8 (13.6)	0.676
Time interval of IgM antibody seroconversion, days
From positive to negative	13.00 (6.00−33.75)	7.50 (4.75−11.50)	25.50 (6.75−56.75)	0.030
From positive to weak positive	16.00 (3.00−28.00)	12.00 (12.00−12.00)	19.00 (3.00−30.00)	0.694
Consistent negative	11.50 (7.00−25.50)	27.00 (10.00−37.00)	11.00 (7.00−22.50)	0.186
Consistent positive	9.00 (8.00−13.00)	13.00 (13.00−13.00)	8.50 (7.50−14.50)	0.558
Seroconversion of IgG antibody				0.059
From positive to negative	10 (13.5)	4 (26.7)	6 (10.2)	0.110
From positive to weak positive	13 (17.6)	4 (26.7)	9 (15.3)	0.446
Consistent negative	7 (9.5)	2 (13.3)	5 (8.5)	0.624
Consistent positive	44 (59.5)	5 (33.3)	39 (66.1)	0.037
Time interval of IgG antibody seroconversion, days
From positive to negative	24.00 (10.00−48.00)	24.00 (9.25−58.75)	27.50 (10.00−48.00)	1.000
From positive to weak positive	7.00 (4.00−22.00)	5.50 (4.25−7.75)	11.00 (4.00−30.00)	0.279
Consistent negative	10.00 (7.50−18.50)	9.00 (8.50−9.50)	12.00 (7.00−25.00)	0.699
Consistent positive	13.50 (6.75−24.00)	13.00 (12.00−14.00)	14.00 (6.00−25.00)	0.970

Data are median (IQR), n (%), P values compare using χ² test, Fisher’s exact test, or Kruskal Wallis test. IQR, interquartile range.