Detection of hepatitis B virus DNA in spermatozoa, urine, saliva and leucocytes, of chronic HBsAg carriers. A lack of relationship with serum markers of replication.

Urine, saliva and semen from 18 chronic HBsAg carriers, material that might be concerned in the transmission of hepatitis B virus infection, was examined for the presence of HBV-DNA using molecular hybridisation. HBV-DNA was detected in samples from 14 patients: semen was positive in all of these, saliva in 12 and urine in 10. Autoradiographic studies indicated that HBV-DNA was present in the free form in all cases and in 10, higher molecular weight bands were also observed. While the latter suggested integration of HBV-DNA into host chromosome, resolution to 3.2 Kb following digestion with Eco RI in every case was more consistent with the HBV-DNA being free. In a further group of patients peripheral blood leucocytes were also found to contain HBV-DNA and were the likely source of HBV-DNA in saliva and urine, while in semen both spermatozoa and mononuclear cells contained HBV-DNA. Moreover, free HBV-DNA was identified in the semen of patients without markers of viral replication in serum indicating that sexual transmission could still occur and this is of importance in relation to current vaccination policies.