TABLE 2.

N antigen detection in sera by a capture ELISA

Days after onset of symptoms	No. of patients with positive sera/total no. of patients with SARS (%)
0-2	NA
3-5	4/8 (50)
6-10	10/14 (71)
11-15	3/6 (50)
16-20	1/3 (33)
21-30	0/6 (0)
31-60	0/15 (0)
61-90	0/8 (0)