Natural History of Chronic Hepatitis B Virus Infection: What We Knew in 1981 and What We Know in 2005

Abstract

Natural History of Chronic Hepatitis B Virus Infection: What We Knew in 1981Progression From Acute to Chronic Infection. Epidemiological and clinical studies estimated that approximately 10% of patients with acute hepatitis B virus (HBV) infection progress to chronic infection. 1 Recovery from acute HBV infection with hepatitis B surface antigen (HBsAg) to antibody (anti-HBs) seroconversion was thought to indicate virus clearance.Markers of HBV Replication and Significance of Hepatitis B e Antigen. In 1981, evaluation of hepatitis B patients relied on serology assays. 2,3 It was recognized that infectivity of HBV carriers varied and hepatitis B e antigen (HBeAg) was a reliable marker of infectivity. 3 HBV was known to be a DNA virus, and many investigators were developing assays to measure HBV DNA polymerase activity and later HBV DNA level. [4][5][6] These assays relied on hybridization techniques with a lower limit of detection of approximately 10 6 copies/mL, and most assays were semi-quantitative. 5,6

Clearance of hepatitis B surface antigen and risk of hepatocellular carcinoma in a cohort chronically infected with hepatitis B virus

“…However, up to 90% of infants, 30% of children under 5 years of age, and between 5% and 10% of adults develop chronic infection. 2 Chronic HBV infection is confirmed by the presence of hepatitis B surface antigen (HBsAg) in serum for at least 6 months and is characterized by several clinical phases: the immune tolerant, immune active, or clearance and inactive phases. 3 The immune tolerant phase usually follows perinatal infection and is characterized by the presence of hepatitis B e antigen (HBeAg), high levels of HBV DNA, normal levels of alanine aminotransferase (ALT), and minimal or no liver inflammation.…”

Serological and molecular epidemiological outcomes after two decades of universal infant hepatitis B virus (HBV) vaccination in Nunavut, Canada

“…The immune-active phase is characterized by presence or absence of HBeAg, high HBV DNA levels (>2000 IU/ml), elevation in ALT levels, and active inflammation [21]. Immunemediated lysis of infected hepatocytes by increased T-cell response occurs, leading to flares of aminotransferases.…”

An economic evaluation of contingency management for completion of hepatitis B vaccination in those on treatment for opiate dependence

“…The structure of the model follows the representation of the natural course of HBV in previous systematic reviews describing the natural history of HBV infection 15, 16, 17, 18 and previous economic evaluations 19, 20, 21, 22. The incidence of HBV was estimated from cross‐sectional survey data from the national Unlinked Anonymous Monitoring Survey, which provide robust estimates of prevalence trends of HBV infection and self‐reported vaccination among current and past injectors in the United Kingdom.…”

“…The model tracks progression through HBV disease states. Health states and transitions between health states were based on descriptions of the natural history of HBV infection in existing systematic reviews 15, 16, 17, 18 and on published economic models, including HBV 19, 20, 21, 22. The economic model differentiates periods where individuals are at increased risk of HBV infection (are in the PWID population) and where individuals at lower risk of HBV infection (are ex‐PWID).…”

“…The transition probabilities characterizing the natural history of HBV were derived from the published literature (Table 1) 15, 16, 17, 18, 29. Lacking data for PWID, transitions between HBV health states among the general population were used.…”