[Hepatitis B and C: biology and molecular diagnosis].

Viral infections are major causes of chronic liver diseases. The etiologic agents are hepatitis B virus (HBV), hepatitis C virus (HCV) and the HBV-associated hepatitis delta virus (HDV). The biology and molecular structure of these viruses have been studied in great detail. In general, these viral infections can be detected by serological tests and molecular techniques, including hybridization analyses (dot blot, Southern blot or Northern blot and in situ hybridization) as well as polymerase chain reaction (PCR) amplification and in situ PCR. The sensitive and specific identification of HBV and HCV is clinically relevant both for epidemiologic-preventive as well as for therapeutic reasons.