title: Reversion of duck hepatitis B virus DNA replication in vivo following cessation of treatment with the nucleoside analogue ganciclovir.
abstract: In order to define, in more detail, the virological events which occur after completion of antiviral chemotherapy, ducks congenitally infected with the duck hepatitis B virus (DHBV) were treated for 4 weeks with the nucleoside analogue ganciclovir and followed up over a 7-day period. Specimens of serum and liver were collected daily during follow-up for virological analysis. Treatment resulted in a substantial reduction in both viraemia and liver DHBV DNA replicative intermediates. However, after cessation of treatment, viraemia returned to detectable levels within 4 days. In the liver, the viral supercoiled DNA (SC DNA) was the form least affected by therapy and returned to near control levels by day 2 post-treatment. The other hepatic replicative intermediates reached pretreatment levels within 4 days of cessation of therapy. This study has defined the kinetics of relapse of viral replication after completion of antiviral therapy in the duck hepatitis B model. Of all viral replicative forms, the SC DNA appears to be the one which is most resistant to nucleoside analogue therapy and is presumably responsible for the relapse phenomenon observed post-treatment.
mesh_terms: D000818:Animals; D004261:DNA Replication / Q000187:drug effects*; D004279:DNA, Viral / Q000096:biosynthesis / Q000097:blood / Q000187:drug effects*; D015774:Ganciclovir / Q000494:pharmacology*; D018347:Hepadnaviridae Infections / Q000097:blood / Q000188:drug therapy* / Q000821:virology; D015611:Hepatitis B Virus, Duck / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D008099:Liver / Q000821:virology; D009705:Nucleosides / Q000627:therapeutic use; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D004279:DNA, Viral; D009705:Nucleosides; D015774:Ganciclovir