[Recent advances in understanding and diagnosing hepatitis B virus infection].

Hepatitis B virus (HBV) infects approximately 257 million individuals worldwide. Recent advances in the virology and diagnosis of HBV infection are summarized in this review article. A novel classification of the different phases of chronic HBV infection, proposed by the European Association for the Study of the Liver (EASL), is presented. New diagnostic and monitoring tools are now available, including rapid diagnostic tests for hepatitis B surface antigen (HBsAg) detection, HBsAg quantification assays, an HBV core-related antigen (HBcrAg) quantification test, and HBV RNA quantification testing. Their clinical utility under study is discussed in this review.