Levels of viraemia in subjects with serological markers of past or chronichepatitis B virus infection

Subjects with serological markers for a past HBV infection may still have H BV DNA in their serum, but the levels of viraemia in such cases are not kno wn. In the present study, of 63 consecutive HBsAg-negative, anti-HBc-positi ve serum samples with or without anti-HBs, 20 were HBV DNA-positive as anal ysed bl a highly sensitive quantitative PCR, the Cobas Amplicor HBV Monitor test. However, all of these 20 samples had viraemia levels below 1000 copi es/ml, compared with median viraemia levels of 10(8.6) and 10(4.3) copies/m l, respectively, in 98 HBeAg-positive and 124 HBeAg-negative HBsAg carriers . There was no difference in viraemia between subjects with anti-HBc alone compared with both anti-HBs and anti-HBc, nor between those with or without hepatitis C virus antibodies. The findings indicate that HBsAg-negative su bjects may retain a low infectivity. Their risk for progressive liver damag e is probably lon, but this deserves further study.