Table 3.

Detection of IgM, IgG and IgM/IgG antibodies against SARS-CoV-2 with the three ICT strip assays in positive and negative RT-PCR patients along three periods of time since the onset of symptoms

			PCR
			Early stage			Intermediate stage			Late stage
			Positive	Negative	Total	Positive	Negative	Total	Positive	Negative	Total
Sienna® (n = 142)	IgM	Positive	13	4	17	33	2	35	8	3	11
		Negative	28	22	50	15	7	22	1	6	7
		Total	41	26	67	48	9	57	9	9	18
	IgG	Positive	11	1	12	33	4	37	7	2	9
		Negative	30	25	55	15	5	20	2	7	9
		Total	41	26	67	48	9	57	9	9	18
	IgM/IgG	Positive	15	4	19	39	4	43	9	3	12
		Negative	26	22	48	9	5	14	0	6	6
		Total	41	26	67	48	9	57	9	9	18
Wondfo® (n = 114)	IgM/IgG	Positive	7	3	10	20	4	24	5	1	6
		Negative	30	23	53	7	5	12	1	8	9
		Total	37	26	63	27	9	36	6	9	15
Prometheus® (n = 88)	IgM	Positive	20	22	42	10	5	15	2	6	8
		Negative	15	3	18	1	2	3	0	2	2
		Total	35	25	60	11	7	18	2	8	10
	IgG	Positive	14	10	24	7	4	11	1	2	3
		Negative	21	15	36	4	3	7	1	6	7
		Total	35	25	60	11	7	18	2	8	10
	IgM/IgG	Positive	24	23	47	10	6	16	2	6	8
		Negative	11	2	13	1	1	2	0	2	2
		Total	35	25	60	11	7	18	2	8	10