Prevalence of hepatitis B virus infection among atomic bomb survivors

The aim of this study was to determine whether the prevalence of hepatitis B virus (HBV) carriers increased with atomic bomb radiation dose, and whether radiation decreased the ability to clear HBV among the atomic bomb survivors. The study subjects were 6,121 participants in the Adult Health Study of atomic bomb survivors in Hiroshima and Nagasaki. After adjustment for age, sex, city and potential confounders, the rates of seropositivity for hepatitis B surface antigen (HBsAg), indicating current HBV infections, and anti-hepatitis B core antibody, indicating either cured or current infections, increased with radiation dose. However, no relationship was observed between radiation and anti-hepatitis B surface antibody (indicating cured infection). The proportion of persons who were unable to clear the virus, as the proportion of HBsAg-positive persons among those ever infected by HBV (positive for HBsAg or surface or core hepatitis B antibody), increased significantly with radiation dose among those receiving blood transfusions. This proportion was not related to dose among those who reported no such transfusions. The findings may suggest a lower likelihood of clearance after HBV infection among those who were more likely to have been infected with HBV as adults after atomic bomb irradiation rather than as infants or adults prior to irradiation.     

Immunology of hepatitis B virus and hepatitis C virus infection

More than 500 million people worldwide are persistently infected with the hepatitis B virus (HBV) and/or hepatitis C virus (HCV) and are at risk of developing chronic liver disease, cirrhosis and hepatocellular carcinoma. Despite many common features in the pathogenesis of HBV- and HCV-related liver disease, these viruses markedly differ in their virological properties and in their immune escape and survival strategies. This review assesses recent advances in our understanding of viral hepatitis, contrasts mechanisms of virus-host interaction in acute hepatitis B and hepatitis C, and outlines areas for future studies.     

Animal models for the study of hepatitis B virus infection

Even with an effective vaccine, an estimated 240 million people are chronically infected with hepatitis B virus(HBV) worldwide. Current antiviral therapies,including interferon and nucleot(s)ide analogues,rarely cure chronic hepatitis B. Animal models are very crucial for understanding the pathogenesis of chronic hepatitis B and developing new therapeutic drugs or strategies. HBV can only infect humans and chimpanzees, with the use of chimpanzees in HBV research strongly restricted. Thus, most advances in HBV research have been gained using mouse models with HBV replication or infection or models with HBV-related hepadnaviral infection. This review summarizes the animal models currently available for the study of HBV infection.     

Immunopathogenesis of hepatitis B virus infection

Hepatitis B virus (HBV) infection is a non-cytopathic hepatotropic virus that can lead to severe liver disease including acute hepatitis, cirrhosis and hepatocellular carcinoma. Successful clearance of the virus as well as the establishment of liver disease is largely driven by a complex interaction between the virus and the host immune response. In this review, the immunological events, including both the innate and adaptive immune response are discussed in the setting of both acute and chronic HBV infection and liver disease.     

Dynamics of hepatitis B virus infection

Mathematical models of the dynamics of HIV and hepatitis C virus infection have proven to be of great utility in understanding pathogenesis and designing better treatments. Here, we review the state of the art in modeling and interpreting data obtained from hepatitis B virus infected patients treated with antiviral agents.     

Antisense therapy of hepatitis B virus infection

Chronic infection with the hepatitis B virus (HBV) is a major health problem worldwide. The only established therapy is interferon-a with an efficacy of only 30–40% in highly selected patients. The discovery of animal viruses closely related to the HBV has contributed to active research on antiviral therapy of chronic hepatitis B. The animal model tested and described in this article are Peking ducks infected with the duck hepatitis B virus (DHBV). Molecular therapeutic strategies aimed at blocking gene expression include antisense DNA. An antisense oligodeoxynucleotide directed against the 5′-region of the preS gene of DHBV inhibited viral replication and gene expression in vitro in primary duck hepatocytes and in vivo in Peking ducks. These results demonstrate the potential clinical use of antisense DNA as antiviral therapeutics.     

The earliest steps in hepatitis B virus infection

The early steps in hepatitis B virus (HBV) infection, a human hepadnavirus, initiates from cell attachment followed by entry and delivery of the genetic information to the nucleus. Despite the fact that these steps determine the virus-related pathogenesis, their molecular basis is poorly understood. Cumulative data suggest that this process can be divided to cell attachment, endocytosis, membrane fusion and post-fusion consecutive steps. These steps are likely to be regulated by the viral envelope proteins and by the cellular membrane, receptors and extracellular matrix. In the absence of animal model for HBV, the duck hepadnavirus DHBV turned out to be a fruitful animal model. Therefore data concerning the early, post-attachment steps in hepadnaviral entry are largely based on studies performed with DHBV in primary duck liver hepatocytes. These studies are now starting to illuminate the mechanisms of hepadnavirus route of cell entry and to provide some new insights on the molecular basis of the strict species specificity of hepadnavirus infection.     

The earliest steps in hepatitis B virus infection

The early steps in hepatitis B virus (HBV) infection, a human hepadnavirus, initiates from cell attachment followed by entry and delivery of the genetic information to the nucleus. Despite the fact that these steps determine the virus-related pathogenesis, their molecular basis is poorly understood. Cumulative data suggest that this process can be divided to cell attachment, endocytosis, membrane fusion and post-fusion consecutive steps. These steps are likely to be regulated by the viral envelope proteins and by the cellular membrane, receptors and extracellular matrix. In the absence of animal model for HBV, the duck hepadnavirus DHBV turned out to be a fruitful animal model. Therefore data concerning the early, post-attachment steps in hepadnaviral entry are largely based on studies performed with DHBV in primary duck liver hepatocytes. These studies are now starting to illuminate the mechanisms of hepadnavirus route of cell entry and to provide some new insights on the molecular basis of the strict species specificity of hepadnavirus infection.     

Effect of concurrent acute infection with hepatitis C virus on acute hepatitis B virus infection.

OBJECTIVE--To investigate the possible interference with acute hepatitis B virus infection by co-infection with hepatitis C virus. DESIGN--Analysis of stored sera collected for transfusion transmitted viruses study in 1970s. SETTING--Four major medical centres in the United States. PATIENTS--12 recipients of blood infected with hepatitis B virus. MAIN OUTCOME MEASURES--In 1970s, presence of antibodies in hepatitis B virus and raised serum alanine aminotransferase concentration; detection of antibodies to hepatitis C virus with new enzyme linked immunoassays. RESULTS--Five of the 12 patients were coinfected with hepatitis C virus. Hepatitis B surface antigen was first detected at day 59 in patients infected with hepatitis B virus alone and at day 97 in those coinfected with hepatitis C virus (p = 0.01); median durations of antigenaemia were 83 and 21 days respectively (p = 0.05), and the antigen concentration was lower in the coinfected patients. Alanine aminotransferase patterns were uniphasic when hepatitis B virus infection occurred alone (range 479-2465 IU/l) and biphasic in patients with combined acute infection (no value > 380 IU/l; p = 0.0025). Four coinfected recipients developed chronic hepatitis C virus infection. The fifth patient was followed for only four months. CONCLUSIONS--Acute coinfection with hepatitis C virus and hepatitis B virus inhibits hepatitis B virus infection in humans, and onset of hepatitis B may reduce the severity of hepatitis C virus infection but not frequency of chronicity. Alanine aminotransferase concentration showed a biphasic pattern in dual infection.     

Seroepidemiologic study of adult T-cell leukemia virus (ATLV) and hepatitis B virus infection in Okinawa, Japan

A total of 2,283 serum samples were collected from healthy subjects in three islands of the Yaeyama district of Okinawa, Japan. These sera were tested for the presence of hepatitis B surface antigen (HBsAg), for antibody to hepatitis B core antigen (anti-HBc), and for antibody to adult T-cell leukemia-associated antigen (anti-ATLA). Correlation between hepatitis B virus infection and adult T-cell leukemia virus (ATLV) infection was determined by using the prevalence rates for three virus markers. Overall prevalence of HBsAg, anti-HBc and anti-ATLA was 6.5%, 57.4%, and 17.9%, respectively. Age-specific prevalence of anti-HBc and anti-ATLA increased with age, but that of HBsAg did not. Sex-specific prevalence of HBsAg was significantly higher in males than in females, but that of anti-ATLA was significantly higher in females than in males. Statistical analysis revealed that prevalence of anti-ATLA was significantly higher in HBsAg-positive persons and HBsAg-negative/anti-HBc-positive persons than in those negative for HBsAg and anti-HBc. These data suggest that hepatitis B virus-infected persons have a significantly higher chance of adult T-cell leukemia virus infection than those without hepatitis B virus infection in the area studied.     

Large-scale survey of hepatitis B virus infection in families

To investigate HBV transmission in families on three islands in Okinawa, Japan, prevalence of HBV markers in two groups of inhabitants was determined. One group consisted of members of families in which there was at least one HBsAg carrier (carrier families); the other group consisted of members of families in which there were no HBsAg carriers (non-carrier families). A total of 3,261 serum samples were collected from subjects on Iriomote Island, Hateruma Island, and Yonaguni Island. These samples were tested for HBsAg by reversed passive hemagglutination (RPHA) and for antibody to hepatitis B core antigen (anti-HBc) by radioimmunoassay. Overall prevalences of HBsAg and anti-HBc were 8.2 and 65.8 per cent respectively. The prevalence of anti-HBC among members of carrier families (80.8%) was significantly higher than that among members of non-carrier families (61.6%) (P less than 0.001). The prevalence of anti-HBc among members of carrier families was higher in all age groups, and was particularly so in children. Within carrier families, the prevalence of anti-HBc was significantly higher in families in which there was at least one HBsAg carrier with HBeAg (94.5%) than in families with no HBeAg-positive carriers (76.1%). This difference was especially marked in young children. These data suggest that in families with HBsAg carrier(s), the risk of transmitting HBV to members, particularly to young children, is higher than in families without carriers, and that the risk is further increased in families with HBeAg-positive carrier(s).     

Occult hepatitis B virus infection among injecting drug users in the Central-West Region of Brazil

The prevalence of occult hepatitis B virus (HBV) infection was investigated in 149 hepatitis B surface antigen (HBsAg) negative injecting drug users (IDUs) in the Central-West Region of Brazil. Of these individuals, 19 were positive for HBV DNA, resulting in an occult HBV infection prevalence of 12.7% (19/149); six of these 19 individuals had anti-HBV core and/or anti-HBV surface antibodies and 13 were negative for HBV markers. All IDUs with occult hepatitis B reported sexual and/or parenteral risk behaviours. All HBV DNA-positive samples were successfully genotyped. Genotype D was the most common (17/19), followed by genotype A (2/19). These findings reveal a high prevalence of occult HBV infection and the predominance of genotype D among IDUs in Brazil''s Central-West Region.     

乙型肝炎病毒宫内感染危险因素的病例对照研究

目的:探讨与乙型肝炎病毒宫内感染相关的产妇孕期危险因素.方法:采用病例对照的研究方法,选择连续收集的2005年10月至2006年10月在陕西省妇幼保健院产科行孕期检查并分娩的113例乙型肝炎病毒表面抗原(HBsAg)阳性产妇及其所产新生儿为研究对象,以出生时血清HBsAg阳性的新生儿为病例组,其余均为对照组,收集产妇孕期及产时的相关资料,采用单因素分析、对数线性模型等方法分析与宫内感染相关的因素.结果:113例新生儿有3例发生宫内感染.病例组产妇孕中期有性行为、HBVDNA阳性与对照组之间存在统计学差异(P＜0.05),且交互作用分析显示二者之间符合相乘模型,OR值及95%CI为127.00(4.73-340.51),有协同作用.其他因素与HBV宫内感染无统计学关联.结论:孕中期性行为及产妇HBV DNA阳性可能增加新生儿HBV宫内感染的危险性.     

Non-B hepatitis in Melbourne: a serological study of hepatitis A virus infection.

A study was performed to establish the value of immune adherence haemagglutination tests for antibody to hepatitis A virus in the diagnosis of non-B hepatitis. Infection with hepatitis A virus was confirmed in 14 out of 16 patients from six families and seven out of nine patients in whom the source of infection was unknown. One additional patient, who had had two episodes of jaundice, was shown to have had an attack of hepatitis A followed by an attack of hepatitis B. In patients with acute hepatitis A antibody detectable by immune adherence haemagglutination becomes detectable three or four weeks after the onset of symptoms and reaches peak levels about five weeks later.     

Detection of hepatitis B virus in bone allografts from donors with occult hepatitis B infection

The implementation of nucleic acid testing in donor screening has improved the safety of tissue allografts. Although infectious disease transmission can be considered a rare event, the detection of occult hepatitis B infection remains challenging. The studies concerning this risk are mainly based on testing blood specimens. This work shows the correlation between results of samples obtained from donor blood and the corresponding tissue washing solution. Hepatitis B virus deoxyribonucleic acid was detected both in bone allografts from donors with serological profiles associated to active hepatitis B infection and occult hepatitis B infection. These results suggest that hepatitis B virus seems to concentrate in bone marrow even when a low viral load is present in peripheral blood. Even detection at molecular level is not enough to avoid the risk of hepatitis B virus transmission and a multiparametrical evaluation is required in tissue donor screening. The role of clinicians in recognition and reporting of allograft-associated infections is a major concern for the acquisition of experience to be applied in risk control of disease transmission.