ABSTRACT
The results of detection for anti-HBc IgM in 6 acute hepatitis B cases and a group of individuals with subclinical infection in an epidemic of HB were reported in this paper. The authors had followed up 5 children with subclinical HB infection for 6-7 months and found that the anti-HBc IgM in their sera became negative or declined while anti-HBs became positive. The results showed that the marker of anti-HBc IgM could be used as an indicator of recent subclinical HB infection. This result is valuable in epide-miological survey of HB in general population. The geometric mean values (GMV) of S/N of anti-HBc IgM during the "window period" and the period of seroconversion to anti-HBs in subclinical infection were 3.9 and 1.9, respectively, and were lower than in clinical infection (6.9 and 7.4, respectively). Furthermore, the duration of that was shorter. The phenomenon is worthy of studying further. During the early convalescence, i. e., the period of seroconversion to anti-HBs in patients with acute hepatitis B, the GMV of S/N of anti-HBc IgM was high up to 7.4, which indicated that they might also be infectious.