Table 2.

Positive rate of anti-SARS-CoV-2 IgM antibody according to the different kits used.

IgM antibody
Days after onset	No. of samples	Hangzhou AllTest		SD BIOSENSOR		Vazyme
		No. of positive samples	Positive rate (%)	No. of positive samples	Positive rate (%)	No. of positive samples	Positive rate (%)
0–4	11	2	18.2	2	18.2	2	18.2
5–9	26	5	19.2	9	34.6	3	11.5
10–14	29	7	24.1	21	72.4	5	17.2
15–19	24	4	16.7	21	87.5	5	20.8
20–35	9	3	33.3	7	77.8	0	0.0