Perinatal transmission of hepatitis B virus and its prevention

Hepatitis B vaccine birth dose coverage among hepatitis B-exposed and hepatitis B-unexposed infants: evidence from the Healthy Beginning Initiative program in Benue State, Nigeria

Introduction

Nigeria offers universal hepatitis B birth-dose vaccine (HepB-BD) for the prevention and control of hepatitis B (HepB). While prior studies suggest low coverage of HepB-BD in Nigeria, there is a paucity of evidence on the association between the uptake of HepB-BD and maternal HepB status. This study aimed to determine HepB-BD coverage and the associated factors among infants of HepB-positive and -negative women in Nigeria.

Methods

the study was a secondary analysis of data from the Healthy Beginning Initiative program conducted between June 2016 and October 2018 in Benue State, Nigeria. The analysis was restricted to data from a cohort of 6269 mothers who had HepB screening during pregnancy and completed the HepB infant immunization question in the post-delivery survey. The association between the coverage of HepB-BD and maternal HepB status, sociodemographic characteristics, and obstetric factors were determined using crude and adjusted relative risks.

Results

about 10% of the women tested HepB positive. The coverage of HepB-BD was 64% (63.2% among infants of HepB-positive mothers and 63.8% among HepB-negative mothers). The likelihood of infants of HepB-positive mothers receiving HepB-BD was not significantly different from infants of HepB-negative mothers (aRR=0.97, 95%CI= 0.92-1.04). Among HepB-positive mothers, infants of mothers younger than 20 years (aRR=1.49, 95%CI=1.03-2.16) or those who received antenatal care (aRR=1.41, 95%CI=1.16-1.71) were more likely to receive HepB-BD, while mothers with no previous pregnancies (aRR=0.73, 95%CI=0.59-0.91) were less likely to receive HepB-BD. Among HepB-negative mothers, infants of less-educated mothers were less likely to receive HepB-BD (aRR=0.96, 95%CI=0.92-0.99), whereas infants of mothers who received antenatal care (aRR=1.23, 95%CI=1.16-1.31) or had an institutional delivery were more likely (aRR=1.29, 95%CI=1.23-1.36) to receive HepB-BD. Conclusion: our findings highlight the need to improve HepB-BD uptake, particularly among HepB-exposed infants who are at risk of perinatal transmission of HepB.

Burden of chronic hepatitis B and C infections in 2015 and future trends in Japan: A simulation study

Background

Determining the number of chronic hepatitis B (HBV) and C virus (HCV) infections is essential to assess the progress towards the World Health Organization 2030 viral hepatitis elimination goals. Using data from the Japanese National Database (NDB), we calculated the number of chronic HBV and HCV infections in 2015 and predicted the trend until 2035.

Methods

NDB and first-time blood donors data were used to calculate the number of chronic HBV and HCV infections in 2015. A Markov simulation was applied to predict chronic infections until 2035 using transition probabilities calculated from NDB data.

Findings

The total number of chronic HBV and HCV infections in 2015 in Japan was 1,905,187–2,490,873 (HCV:877,841–1,302,179, HBV:1,027,346–1,188,694), of which 923,661–1,509,347 were undiagnosed or diagnosed but not linked to care (“not engaged in care”), and 981,526 were engaged in care. Chronic HBV and HCV infections are expected to be 923,313–1,304,598 in 2030, and 739,118–1,045,884 in 2035. Compared to 2015, by 2035, the number of persons with HCV not engaged in care will decline by 59·8 – 76·1% and 86·5% for patients in care. For HBV, a 47·3 – 49·3% decrease is expected for persons not engaged in care and a decline of 26·0% for patients engaged in care.

Interpretation

Although the burden of HBV and HCV is expected to decrease by 2035, challenges in controlling hepatitis remain. Improved and innovative screening strategies with linkage to care for HCV cases, and a functional cure for HBV are needed.

Funding

Japan Ministry of Health, Labour and Welfare.

The coverage of hepatitis B birth dose vaccination in Nigeria: Does the place of delivery matter?

BACKGROUND

Hepatitis B birth dose (HepB-BD) vaccination coverage remains suboptimal in Nigeria. While evidence suggests that institutional delivery is associated with the uptake of HepB-BD vaccine, little is known about how the uptake differs by facility ownership (public or private). This study examined the HepB-BD vaccination coverage by place of delivery in Nigeria.

METHODS

This study is a secondary analysis of data on 6143 children aged 12-23 mo obtained from the 2018 Nigeria Demographic and Health Survey. We assessed the association between HepB-BD vaccination and the place of delivery using logistic regression models.

RESULTS

About 53% of the children received the HepB-BD vaccine. Approximately 77, 83 and 33% of those delivered at a public health facility, private health facility and at home received the HepB-BD vaccine, respectively. After controlling for child- and maternal-level factors, the odds of receiving HepB-BD vaccine were significantly lower in children delivered at a private health facility (adjusted OR [aOR]=0.77, 95% CI 0.59 to 0.99) or at home (aOR=0.48, 95% CI 0.36 to 0.63). Wealth index and region of residence were significantly associated with the receipt of HepB-BD vaccination in all three places of delivery.

CONCLUSIONS

Children are less likely to receive the HepB-BD vaccine if they are delivered at a private health facility or at home. There is a need for private health sector engagement for immunization service delivery and innovative community-based interventions to reach the children delivered at home.

The Administration of Tenofovir Disoproxil Fumarate for Pregnant Japanese Women with Chronic Hepatitis B

The appropriate management of hepatitis B virus (HBV) infection during pregnancy has not been established in Japan. We herein report five HBV-infected pregnant Japanese women who received tenofovir disoproxil fumarate (TDF). Two of them had been born after the introduction of nationwide immunoprophylaxis and were vertically infected with HBV, highlighting the need to address mother-to-child transmission further. In both entecavir-experienced and nucleoside/nucleotide analog-naïve mothers, TDF suppressed HBV replication without serious adverse events. All five children were free from congenital disorders, growth impairment, and HBV infection. TDF showed safety and efficacy for pregnant woman with chronic hepatitis B and might have helped prevent mother-to-child transmission.

The prevalence of hepatitis B virus infection in HIV-positive and HIV-negative infants: KwaZulu-Natal, South Africa

Background

The prevalence of hepatitis B virus (HBV) amongst South African infants and children has been reported in the pre-HIV era. Despite the reported high prevalence of HIV in the general population of South Africa, the rate of HIV/HBV co-infection amongst infants and children remains poorly reported.

Objectives

We describe the prevalence of HBV infection amongst HIV-positive and HIV-negative infants by molecular methods of diagnosis using dried blood spot samples.

Methods

This retrospective cross-sectional study was conducted between July 2011 and December 2011 in an academic referral laboratory offering viral diagnostic services to the entire KwaZulu-Natal province of South Africa. A total of 322 study samples were collected from discarded residual dried blood spot samples following routine infant diagnosis of HIV. Equal proportions of HIV-positive and HIV-negative infant specimens were studied. Statistical differences in the prevalence of HBV between the HIV-positive and HIV-negative samples were calculated using the Pearson chi-square test, and a p-value < 0.05 was considered statistically significant. Further testing for HBV DNA using a nested polymerase chain reaction method was performed.

Results

The overall prevalence of HBV was 10%. In the HIV-positive group, 21 of 161 infants tested positive for HBV compared with 12 of 161 HIV-negative infants who tested positive for HBV. The proportion of infants infected with HBV was marginally higher amongst HIV-positive infants (13.0%; 95% CI 6.8–19.9) compared with HIV-negative infants (7.5%; 95% CI 2.5–13.7; P = 0.098), though not statistically significant.

Conclusion

The finding of a 10% HBV prevalence in this infant cohort is clinically significant. The non-statistically significant difference in HBV prevalence between the HIV-positive and HIV-negative infants suggests that high prevalence of HBV infection in children may be a problem independent of HIV.

Seroepidemiological study of hepatitis B virus markers in Japan

BACKGROUND

In Japan, since 1986, selective vaccination has been implemented as a hepatitis B prevention strategy. The target of vaccination is the infant born to a hepatitis B surface antigen (HBsAg)-positive mother. The current Japanese hepatitis B prevention strategy focuses on reducing the number of HBV carriers but overlooks the risk to susceptible populations. We conducted a nationwide HBV seroepidemiological study to explore the next hepatitis B control strategy.

METHODS

We used sera derived from healthy individuals collected nationwide from 2005 through 2011 to investigate the HBsAg seroprevalence among children aged 4-9 years and 10-15 years (3000 samples) and hepatitis B core antibody (HBcAb) seroprevalence among people 10-39 years of age (600 samples).

FINDINGS

Among sera from 3000 children, 5 (0.17%) specimens were HBsAg-positive. There was no significant difference in HBsAg prevalence between age groups. Among 600 samples, 15 (2.5%) were HBcAb-positive. Out of 15 samples, 4 were from teenagers. Both HBsAg- and HBcAb-positive sera were found mainly in the Southern area of Japan.

CONCLUSION

The prevalence of HBsAg among children was 0.17% in the present study. This is higher than the prevalence reported in previous studies performed in the local area or in blood donors. The prevalence of HBcAb is also higher than we estimated. One of the reasons for this discrepancy from previous studies may be due to the small sample size and the impact of HBV high-endemic areas included in the present nationwide study. Nevertheless, our findings revealed that the opportunities for acquiring HBV infection in the susceptible population were more frequent than we thought, especially in some localities. Hepatitis B vaccination should be introduced into the routine child immunization program for susceptible populations, and the selective vaccination program should be continued for high-risk children.

Transmission route and genotype of chronic hepatitis B virus infection in children in Japan between 1976 and 2010: A retrospective, multicenter study

AIM

The aim of this study was to clarify the trends of the infectious source of chronic hepatitis B virus (HBV) infection and the HBV genotype in the Japanese pediatric population over the last three decades.

METHODS

The present study was a retrospective, nationwide, multicenter study. Patients who were under 20 years of age when diagnosed with chronic HBV infection were eligible for enrollment in this study. A total of 430 patients (male/female, 256/174; age at the time of writing, 1-37 years; median age, 14 years; birth year, 1976-2010) from 11 hospitals were evaluated.

RESULTS

The incidence of chronic HBV infection from 1976 to 1980, 1981-1985, 1986-1990, 1991-1995, 1996-2000, 2001-2005 and 2006-2010 was 56, 52, 34, 37, 81, 92 and 78, respectively. Of the 430 patients, 304 (71%), 61 (14%), 11 (3%) and 54 (13%) were infected via mother-to-child transmission, close contact, blood transfusion and unknown source, respectively. After the introduction of perinatal immunoprophylaxis, the rate of mother-to-child transmission increased from 62% during the 1991-1995 period to 86% during the 2006-2010 period. The distributions of genotypes A, B, C, D and F were 3%, 9%, 86%, 2% and 1%, respectively. No obvious change was observed in the distribution of genotypes. Genotype C was significantly associated with mother-to-child transmission.

CONCLUSION

Mother-to-child transmission remains the primary source of chronic HBV infection after the introduction of immunoprophylaxis. Taking measures to prevent immunoprophylaxis failure is essential to reduce pediatric chronic HBV infection in Japan.

Prevalence of hepatitis B virus serologic markers in pregnant patients in Antananarivo, Madagascar

BACKGROUND AND OBJECTIVES

Hepatitis B virus (HBV) infection is a major public health problem in Madagascar. Its severity is related to the risk of chronicity, especially in case of neonatal contamination. Our objectives were to investigate the prevalence of HBV infection among pregnant patients at the Befelatanana obstetrics and gynecology teaching hospital department (BOGTH) by detecting HBsAg and to evaluate the risk of HBV mother to child transmission by screening for HBeAg.

METHODS

We conducted a 6-month prospective study in the BTHOGD from February 2012 to July 2012. All pregnant patients consulting for antenatal care were screened for HBV serologic markers.

RESULTS

The prevalence of HBsAg was 1.9% (20 out 1050 screened patients). The average age was 26.51 years (25-30 years). Most patients tested were unaware of their hepatitis B status and only 0.38% had been vaccinated before pregnancy. Only 1 (5%) of the 20 patients with HBsAg was positive for HBeAg.

CONCLUSION

Hepatitis B is very frequent in pregnant patients in Madagascar and it is recommended that all pregnant patients be routinely screened for HBsAg. This screening of maternal infection would allow applying prophylactic measures to neonates to decrease the risk of disease chronicity.

Estimating numbers of persons with persistent hepatitis B virus infection transmitted vertically and horizontally in the birth cohort during 1950-1985 in Japan

AIM

We estimated numbers of persons, born between 1950 and 1985 in Japan, who were persistently infected with hepatitis B virus (HBV) through vertical and horizontal infections.

METHODS

HBV carrier rates with vertical and horizontal infections were computed using sex- and age-specific prevalence rates of hepatitis B surface antigen (HBsAg) and hepatitis B e-antigen (HBeAg) by mathematical model. Probabilities of vertical HBV transmission in babies born to carrier mothers with and without HBeAg were presumed to be 90% and 10%, respectively.

RESULTS

HBV carrier rates with vertical infection stayed contrast at approximately 0.3% in birth cohorts through 36 years (1950-1985), both in men and women. By a remarkable constant, HBV carrier rates with horizontal infection decreased steadily from 1.43% to 0.10% in men and from 0.95% to 0.03% in women. The estimated total number of HBV carriers born between 1950 and 1985 was 522 500 (355 488-693 606). Of them, the numbers of HBV carriers with vertical and horizontal infections were 197 574 (149 505-288 709) and 324 926 (205 983-404 896); they accounted for 37.81% and 62.19%, respectively, with a ratio of 1:1.64. The ratio between vertical and horizontal infections was 1:2.20 in men and 1:1.06 in women.

CONCLUSION

Vertical HBV infection had stayed constant until immunoprophylaxis of mother-to-baby transmission was implemented in 1986 in Japan. In contrast, horizontal HBV infection decreased over years. The decrease would be due to many factors, including improved socioeconomic environments, advanced medical maneuvers and equipment, and careful vaccination procedures.

Hepatitis B virus and hepatitis C virus infections in United States-bound refugees from Asia and Africa

The aim of this study was to determine the prevalence of active hepatitis B and C virus infections among refugees from various countries in Africa and Asia. Pre-admission serum samples collected during 2002-2007 from refugees originating from Bhutan (N = 755), Myanmar (N = 1076), Iraq (N = 1137), Laos (N = 593), Thailand (N = 622), and Somalia (N = 707) were tested for hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA. The HBV DNA (genotypes A, B, C, and G) was detected in 12.1% of samples negative for anti-HBs. Highest HBV prevalence was found among Hmong; lowest among Bhutanese. The HCV RNA (genotypes 1a, 1b, 1c, 3b, 6n, and 6m) was detected in 1.3% of the samples. Highest HCV prevalence was found among Hmong from Thailand; lowest among Iraqis. Screening specific refugee groups at high risk for viral hepatitis infections will identify infected individuals who could benefit from referral to care and treatment and prevent further transmissions.

Causes of vertical transmission of hepatitis B virus under the at-risk prevention strategy in Japan

The number of hepatitis B virus (HBV) carrier babies has decreased markedly since the introduction in Japan of an "at-risk" strategy for preventing HBV infection. However, elimination of HBV infection from our country appears difficult. To clarify the limitations of the at-risk strategy for preventing vertical transmission of HBV, causes of vertical transmission in a single hospital were retrospectively analyzed. The following causes were presumed in 17 carrier pediatric cases: five patients had prenatal HBV infection, HBV infection during/after the immunization program was confirmed in five cases, two patients had prenatal infection or infection during the immunization program and three cases were caused by human error (by the patients' guardians). Because their mothers were HBV-negative at screening and only developed acute hepatitis B in the perinatal period, another two cases (Cases 3 and 10) did not undergo immunization because they were not subjects of the at-risk strategy. Sequence analyses in ten patients revealed genotype C (subgenotype, C2/Ce) in nine cases and genotype A (subgenotype, A2/Ae) in one case (Case 3). In Japan, HBV subgenotype Ae has recently been found more frequently among sexually active men with acute hepatitis. There are concerns that horizontal transmission of HBV from these men to their pregnant partners could increase. These data suggest clear limitations to the at-risk strategy in Japan and the possibility that the increase in genotype A may influence vertical transmission of HBV.

Clinicoepidemiologic status of mother-to-child infections: a nationwide survey in Japan

We conducted a nationwide survey of the present status of 10 representative mother-to-child infections in Japan. Congenital syphilis, vertical human T-cell leukemia virus type 1 infection, congenital rubella and vertical HIV infection, for which effective preventative strategies have been established, were rare. Cytomegalovirus was the most common congenital pathogen in Japan, although most infants with congenital cytomegalovirus infection may remain undiagnosed.

Hepatitis B knowledge, screening, and vaccination among Hmong Americans

We examined Hmong women and men's knowledge of hepatitis B and their screening and vaccination behavior. In-depth interviews were conducted with Hmong in Oregon aged 18 and older (n=83). Independent samples t-test was used to assess mean differences in knowledge by demographic characteristics. Qualitative data were analyzed using content analysis. Most participants had heard of hepatitis B (96.4%). Fifty-three percent of participants had been screened, and half had been vaccinated (50.6%). Transmission knowledge was significantly higher among younger participants, those born in the U.S., and those who reported seeking preventive care. Sequelae knowledge was significantly higher among those who sought preventive care. Transmission and sequelae knowledge were not associated with screening and vaccination. Qualitative data showed that, of those hepatitis B positive participants, most did not have a comprehensive understanding of their illness. Intervention strategies should address knowledge deficits and improve health literacy, especially among Hmong who have hepatitis B.

Prevalence of hepatitis B infection among young and unsuspecting Hmong blood donors in the Central California Valley

Chronic hepatitis B virus (HBV) infection may result in cirrhosis and/or hepatocellular carcinoma and is one of the leading causes of mortality in Asian Americans including Hmong Americans. The Central California Valley is home to a huge Hmong population. To date, the true prevalence of HBV among Hmong is largely unknown. The aim of this study was to contribute to the limited data on HBV prevalence and its trends in Hmong population in the Central California Valley. Between fiscal years 2006 and 2010, a total of 219, 450 voluntary donors were identified at Central California Blood Center in Fresno. Of these, 821 (399 males and 422 females) were Hmong donors. A cross-sectional review of the HBV (hepatitis B surface antigen) positivity among all donors was carried out. Prevalence estimates with 95% confidence intervals (CI) were calculated. Ninety-two percent of Hmong donors were between age groups 16 and 35 years, and only 8% were ≥36 years. The overall prevalence in Hmong was noted at 3.41% (95%CI 2.3-4.9) compared to 0.06% (95%CI 0.05-0.07) in donors of all ethnicities. The calculated prevalence could be an underestimate of the true HBV prevalence in Hmong as the study enrolled only healthy blood donors with predominant younger age (≤35 years) population. These results underscore the persistent burden of HBV infection and potentially increased risk of premature death even in the second generation Hmong community of the Central California Valley. This study reemphasizes the unequivocal need to develop robust preventive and treatment strategies for HBV in Hmong community.

Molecular imprinting based composite cryogel membranes for purification of anti-hepatitis B surface antibody by fast protein liquid chromatography

In the present study, we have focused our attention to prepare molecular imprinted composite cryogel membranes for purification of hepatitis B surface antibody (anti-HBs) by fast protein liquid chromatography. Before the preparation of the molecular imprinted composite cryogel membranes (MI-CMs) by free radical polymerization at sub-zero temperature, we have synthesized and characterized the anti-HBs imprinted particles. Then, the cryogel membranes (CMs) were characterized by swelling test, scanning electron microscopy and Fourier transform infrared spectroscopy. Prior to chromatographic purification studies, the effective parameters on the anti-HBs adsorption process were evaluated by investigating the dependency of the adsorption capacity on flow-rate, anti-HBs concentration, contact time and ionic strength. The maximum anti-HBs adsorption capacity was calculated as 701.4 mIU/g CM. The selectivity of the MI-CMs was shown by competitive adsorption of anti-HBs, total anti-hepatitis A antibody (anti-HAV) and total immunoglobulin E (IgE) adsorption studies. The MI-CMs have relative selectivity coefficients as 5.45 for anti-HBs/total anti-HAV and 9.05 for anti-HBs/total IgE, respectively. The phosphate buffer solution (pH 7.4) containing 1.0M NaCl was used for elution, almost completely, of adsorbed anti-HBs molecules. The MI-CMs could be used many times without any significant decrease in the adsorption capacity. The chromatographic purification performances of the MI-CMs were also investigated. The chromatographic parameters such as capacity and separation factors, the theoretical plate number and resolution of the MI-CMs were calculated as 5.48, 6.02, 1153.9, and 1.72 for anti-HBs molecules, respectively. As a conclusion, we can say that the MI-CMs could be used for specific purification of anti-HBs from anti-HBs positive human plasma.

Hepatitis B virus infection and pregnancy

Pregnancy only mildly affects that natural progression of acute and chronic infection by the hepatitis B virus (HBV) but it does bring to light three important questions. Mother to child (vertical) transmission risk is best prevented by mandatory HBs antigen testing in all pregnant women in their second trimester and by systemic serovaccination of newborns of infected mothers. In mothers with high viral load, vertical infection in utero could be prevented by lamivudine, telbivudine or tenofovir treatment. Invasive obstetric or gynecological procedures (such as amniocentesis, forceps, etc.) do not seem to increase the risk of vertical infection. Breastfeeding is not contraindicated in maternal HBV infection after serovaccination of the newborn. This holds true for mothers on active treatment with tenofovir which is not absorbed into breast milk. When it comes to managing active antiviral treatment, in absence of virosuppression with lamivudine, tenofovir remains a logical step-up treatment; in absence of virosuppression with adefovir, tenofovir also remains a logical step-up choice as do tenofovir/emtricitabine combinations or lamivudine in absence of preexisting resistance which may have been induced during combination treatment of adefovir and lamivudine. In cases of effective virosuppression with treatment by analogues, lamivudine should be continued and entecavir should eventually be replaced by lamivudine, telbivudine or tenofovir; adefovir should be replaced by tenofovir or lamivudine in absence of resistance (which would require tenofovir therapy) or adefovir which would restrict lamivudine therapy.

Treatment of special populations with chronic hepatitis B infection

All therapeutic agents that are currently in use for the treatment of chronic hepatitis B have been administered to a large number of patients in clinical trials in order to be approved as efficacious and safe. Nevertheless, in these trials, many patients have been excluded either because they have decompensated cirrhosis, or they belong to groups with comorbidities that can seriously affect the underlying liver disease, or where the treatment for chronic hepatitis B virus infection can be contraindicated. Such groups of patients are those with hepatitis D virus, hepatitis C virus and HIV coinfections, patients who have undergone transplantation or are immunosuppressed due to chemotherapy or other treatment, patients with end-stage renal disease under dialysis, acute and fulminant hepatitis B and also, children and pregnant women. In this article, all of the aspects of treatment of these special categories are discussed, since for many of these patients, treatment is of a greater importance compared with the standard patient with chronic hepatitis B, and in real life they represent a great percentage of chronic hepatitis B virus infection patients.

Prevalence of hepatitis B virus (HBV) infection among Hmong immigrants in the San Joaquin Valley

Chronic hepatitis B infection (HBV) is the major cause of primary liver cancer worldwide and Asians are disproportionately affected. The prevalence of HBV among most Asian American groups has been well documented, except in Hmong immigrants in the United States. The aim of this study was to determine the prevalence of HBV among Hmong immigrants in the San Joaquin Valley of California. A convenient sample of 534 Hmong age ≥18 years was recruited at various locations throughout Fresno County. Blood samples from study participants were collected and tested for hepatitis B surface antigen (HBsAg) by enzyme-immunoassay. Two hundred and eighty-nine females and 245 males of Hmong descent (mean age, 43.93) were screened. Eighty-nine (41 males and 48 females) were positive for HBsAg, which accounts for a prevalence of 16.7% (95% C.I. 13.5–19.9). The majorities of HBsAg positive patients were ≥40 years (64.2%), married (66.7%), born in Laos (87.3%), and had lived in the United States ≥20 years (62.5%). Only 37.5% of the participants reported having a primary care physician. Our study revealed that approximately one out of every six Hmong immigrants screened was infected with HBV. Based on our findings, more than one-third of these infected patients have no primary care physician to provide further treatment, surveillance for liver cancer, or vaccination of their families. This supports the Institute of Medicine’s recent recommendations to the Center for Disease Control to engage in a national Hepatitis B surveillance system.

Outbreak of infections by hepatitis B virus genotype A and transmission of genetic drug resistance in patients coinfected with HIV-1 in Japan

The major routes of hepatitis B virus (HBV) infection in Japan has been mother-to-child transmission (MTCT) and blood transfusion. However, HBV cases transmitted through sexual contact are increasing, especially among HIV-1-seropositive patients. To understand the molecular epidemiology of HBV in HBV/HIV-1 coinfection, we analyzed HBV genotypes and HIV-1 subtypes in HBV/HIV-1-coinfected patients at Nagoya Medical Center from 2003 to 2007. Among 394 HIV-1-infected Japanese men having sex with men (MSM) who were newly diagnosed during the study period, 31 (7.9%) tested positive for the hepatitis B virus surface antigen. HBV sequence analyses were successful in 26 cases, with 21 (80.7%) and 5 (19.3%) cases determined as genotypes A and C, respectively. Our finding that HBV genotype A was dominant in HIV-1-seropositive patients alerts clinicians to an alternative outbreak of HBV genotype A in the HIV-1-infected MSM population and a shift in HBV genotype from C to A in Japan. The narrow genetic diversity in genotype A cases suggests that genotype A has been recently introduced into the MSM population and that sexual contacts among MSM were more active than speculated from HIV-1 tree analyses. In addition, we found a lamivudine resistance mutation in one naïve case, suggesting a risk of drug-resistant HBV transmission. As genotype A infection has a higher risk than infection with other genotypes for individuals to become HBV carriers, prevention programs are urgently needed for the target population.

Hepatitis B virus acquisition and pathogenesis in childhood: host genetic determinants

The clinical course of hepatitis B virus (HBV) infection varies from spontaneous recovery to chronic persistent infection leading to severe liver injury. Mounting evidence has recently highlighted the influence of host genotype in the complex interplay between viral and host factors. Studies in adults have suggested the existence of a genetic predisposition to HBV infection secondary to certain defects in the host response. These defects include opsonic deficiency, compromised antigen processing and presentation by human leucocyte antigen variations, attenuated T- and B-cell response, impaired cytokine and chemokine release, and production of receptors for several pertinent factors such as vitamin D and estrogen. By contrast, little is known about the genetic factors involved in the susceptibility to HBV transmission in early childhood. Herein, we review the literature regarding the association between host genetics and susceptibility to primary HBV infection, and we discuss the prospects of investigation in this field. A better understanding of HBV infection immunopathogenesis in the critical period of infancy may allow the development of optimal and innovative prevention and treatment.

Epidemiological survey of Japanese children infected with hepatitis B and C viruses

AIM

  The lack of a nationwide survey on hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in Japan led us to investigate the epidemiological profiles of these infections among Japanese children.

METHODS

  We conducted a questionnaire survey of children (<20 years of age) infected with either HBV (n = 136) or HCV (n = 114), who visited 636 pediatric institutions in Japan from 2003 through 2005. Most HBV-infected subjects (94%) were born in 1986 or after when a nationwide immunization program for infants born to HBe antigen-positive carriers was initiated. The transmission routes were divided into five groups: maternal, horizontal (subdivided into intrafamilial, iatrogenic and other horizontal), and unknown transmission.

RESULTS

  Comparison of subjects born in 1990 or after and those born in 1989 or before, when anti-HBc and anti-HCV (c100-3) screening tests of blood donors began, showed a shift in the relative proportions of maternal, intrafamilial, iatrogenic, other horizontal, and unknown transmission from 52%, 19%, 4%, 7% and 19% to 70%, 14%, 6%, 1% and 9%, respectively, for HBV, which was statistically insignificant (P = 0.120), and from 14%, 0%, 76%, 4% and 7% to 89%, 2%, 4%, 0% and 5%, respectively, for HCV, which was statistically significant (P < 0.001). HBV horizontal transmission did not decrease in proportion. No transfusion-acquired HCV infection was reported in subjects born in 1993 or after.

CONCLUSION

  Maternal transmission is a prominent source of HCV infection among Japanese children. The implementation of measures to prevent HBV horizontal infection is also essential, and the present system of selective vaccination should be expanded to universal vaccination.

A treatment algorithm for the management of chronic hepatitis B virus infection in the United States: 2008 update

Chronic HBV infection is an important public health problem worldwide and in the United States. A treatment algorithm for the management of this disease, published previously by a panel of U.S. hepatologists, has been revised on the basis of new developments in the understanding of the disorder, the availability of more sensitive molecular diagnostic tests, and the licensure of new therapies. In addition, a better understanding of the advantages and disadvantages of new treatments has led to the development of strategies for reducing the rate of resistance associated with oral agents and optimizing treatment outcomes. This updated algorithm was based primarily on available evidence by using a systematic review of the literature. Where data were lacking, the panel relied on clinical experience and consensus expert opinion. The primary aim of antiviral therapy is durable suppression of serum HBV DNA to low or undetectable levels. Assays can now detect serum HBV DNA at levels as low as 10 IU/mL and should be used to establish a baseline level, monitor response to antiviral therapy, and survey for the development of drug resistance. Interferon alfa-2b, lamivudine, adefovir, entecavir, peginterferon alfa-2a, telbivudine, and tenofovir are approved as initial therapy for chronic hepatitis B and have certain advantages and disadvantages. Although all of these agents can be used in selected patients, the preferred first-line treatment choices are entecavir, peginterferon alfa-2a, and tenofovir. Issues for consideration for therapy include efficacy, safety, rate of resistance, method of administration, and cost.

Prevalence of hepatitis B virus infection among women at reproductive age at a German university hospital

BACKGROUND

Mother to infant transmission of hepatitis B virus (HBV) represents a major factor in maintaining chronic infection and depends on the degree of maternal infectivity status.

OBJECTIVES

To examine the seroprevalence of hepatitis B virus surface antigen (HBsAg) in women at reproductive age admitted to the Department of Gynaecology at a German university hospital.

STUDY DESIGN

The seroprevalence of hepatitis B surface antigen (HBsAg) in 5518 women at reproductive age was examined, HBsAg-positive samples were tested for additional HBV markers to verify the infection status.

RESULTS

Out of 5518 samples from women at reproductive age, 88 women (1.59%) were positive for HBsAg and 7 of these HBV-positive women (7.95%) were additionally positive for HBeAg. The majority of the study population were German citizens, however most HBV infected persons originated from countries with a high HBV prevalence. The HBV seroprevalence in our study group is about two times higher compared to the average seroprevalence in the German citizen adult population, thus probably resulting in an underestimation of the infection rate in a multinational setting.

CONCLUSIONS

Screening for HBsAg during pregnancy is still necessary and important for reduction of perinatal HBV transmission even in countries with low HBV prevalence.

Association between the frequency of class II HLA antigens and the susceptibility to intrauterine infection of hepatitis B virus

Multiple factors determine the susceptibility to intrauterine hepatitis B virus (HBV) infection. These factors include the HBV structure, HBV mutation, HBV DNA level, placental barrier, the immune status of the mother, and the genetic make-ups of the newborn infants. Since HLA system is an integral component of the immune response, we hypothesized that the highly polymorphic HLA genes are the key determinants of intrauterine HBV infection. In this study, we selected newborn infants of HBsAg-positive mothers, and divided the infants into 2 groups: intrauterine infection group and non-intrauterine infection group according to the status whether or not they were infected at birth. Each infected infant was compared with 2 controls from the same birth cohort. HLA-DR allele typing was performed using a PCR-sequence specific primer (PCR-SSP) for 24 subjects with intrauterine infection and 48 controls without infection. We found that, among the fifteen (15) HLA-DR alleles assessed, HLA-DRB1*07 was the one, and the only one, significantly in excess (OR = 6.66, P = 0.004) in the intrauterine infection group compared to the non-intrauterine infection group. Our findings thus suggest that high frequency of HLA class II molecules, e.g. HLA-DRB1*07, is associated with the susceptibility of the infants to intrauterine HBV infection.

Prevalence of hepatitis B, C, and delta virus infections among children in Mongolia: progress in childhood immunization

Mongolia is highly endemic for hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis delta virus (HDV) infections among apparently healthy adults. However, the age-specific prevalence of ongoing HBV, HCV, and HDV infections among children in Mongolia remains unknown. Therefore, samples obtained from a total of 655 apparently healthy children of 0.3-15 years of age (307 boys and 348 girls; age, mean +/- standard deviation [SD], 8.4 +/- 4.2 years) living in Mongolia, between October 2005 and January 2006, were tested for serological and molecular markers of HBV, HCV, and HDV infections. Although 88.7% of the 655 children studied were immunized against hepatitis B, 64 (9.8%) tested positive for hepatitis B surface antigen (HBsAg) and/or HBV DNA and 13 (2.0%) for HDV RNA. Twenty-seven children (4.1%) had detectable HCV RNA. Collectively, 82 (12.5%) were viremic for one or more of these viruses, including eight children with dual viremia of HBV/HCV and one child with triple HBV/HCV/HDV viremia. When children without anti-HBc, anti-HCV and anti-HDV IgG (n = 510) served as a control, a history of hospitalization was significantly associated with HBV viremia (P < 0.0001), anti-HBc positivity (P < 0.0001), and HCV viremia (P = 0.0001). HBsAg mutation was found in 18 (31.6%) of the 57 children with viremia, including those at amino acid position 126, 127, 129, 131, 134, 143 or 144. There were no significant differences in the frequency of HBsAg mutation in relation to age, sex, and hepatitis B vaccination status of the children, suggesting that HBsAg mutation plays a limited role in failure of vaccination in Mongolia.

Impact of the universal hepatitis B immunization program in Mongolia: achievements and challenges

BACKGROUND

The impact of the universal infant hepatitis B (HB) immunization program initiated in 1991 in Mongolia is still unclear.

METHODS

A nationwide school-based cross-sectional serosurvey was conducted in 2004, with stratified, multistage, random cluster sampling from all public elementary schools (n=593) in Mongolia. All children were tested for serological markers of hepatitis B virus (HBV).

RESULTS

Serology results were available for 1,145 children (592 boys and 553 girls) aged 7-12 years (survey response rate: 93%). Immunization card was available for 702 (61.3%) children. The coverage of complete HB vaccination was 60.1% and it was increased by birth cohort from 44% to 76%. Significantly higher proportion of children in Metropolitan cities (75.2%) was completely vaccinated with HB compared to those in Province centers (55.7%) and rural areas (59.1%). HBV infection occurred in 5.9%, 13.2%, and 20.8% of complete vaccinees living in Metropolitan, Province centers, and rural areas, respectively; of whom 1.2%, 2.9%, and 8.6% were HB surface antigen (HBsAg) carriers, respectively. Only 17.0% of the children had protective anti-HBs which decreased from 31.1% to 16.3% among 7 to 12-year-olds indicating its decay with time.

CONCLUSIONS

Prevalence of HBV infection and carriage among young generation meaningfully declined compared with those of previous studies in Mongolia. The coverage of birth dose and complete HB vaccination was significantly low in Province centers and rural areas which should be taken into consideration.

Chronic hepatitis B virus infection acquired in childhood: special emphasis on prognostic and therapeutic implication of delayed HBeAg seroconversion

In high endemic areas of hepatitis B virus (HBV) infection, the vast majority of infection is acquired perinatally or during early childhood. The age of the patient is, therefore, almost equivalent to the duration of HBV infection. The natural history of chronic HBV infection consists of three chronological phases: immune tolerance, immune clearance and low replicative phases. The prevalence of hepatitis B e antigen (HBeAg) in asymptomatic HBV carriers is around 90% before 15 years of age, and decreases remarkably to less than 10% after 40 years of age. The immune clearance phase is characterized by a series of hepatitis flares and remissions. These will be followed eventually by HBeAg seroconversion, which is usually accompanied by remission of liver disease and confers favourable outcome. However, patients with persistent HBeAg seropositivity over 40 years of age are associated with a significantly higher risk for progression to cirrhosis than those with HBeAg seroconversion before 40 years of age, and thus should be considered as patients with 'delayed' HBeAg seroconversion. Antiviral or immunomodulatory therapy should be considered seriously for these patients.

A male patient with severe acute hepatitis who was domestically infected with a genotype H hepatitis B virus in Iwate, Japan

Although all eight genotypes of hepatitis B virus (HBV) strains are circulating in Japan, no cases of acute hepatitis with foreign HBV strains of genotype H have thus far been reported in Japan. Here, we report a 35-year-old Japanese patient with severe acute hepatitis who was domestically infected with genotype H HBV. On admission, he had a high HBV load of 1.0 x 10(9) copies/ml, elevated levels of total bilirubin (7.0 mg/dl) and alanine aminotransferase (3606 IU/l), and reduced prothrombin activity of 39.0%. The HB-JAIW05 isolate obtained in the present study was composed of 3215 nucleotides and had the highest similarity of 99.7% with the reported genotype H HBV isolate recovered from a Japanese blood donor. The HB-JAIW05 isolate had neither precore (A1896) nor core promoter (T1762/A1764) mutations. However, upon comparison with the consensus sequence of ten reported HBV isolates of the same genotype, the HB-JAIW05 isolate had 17 nucleotide substitutions including five missense mutations in the P gene, which may be related to vigorous replication of HBV in this case. He had no history of traveling abroad, but had had extramarital sexual contact with two Japanese women living in Iwate, Japan, 2 weeks and 2 months before the disease onset, respectively. Our results suggest that rare HBV genotypes such as H may be spreading in Japan via sexual contact. Further molecular epidemiological studies on HBV to clarify the exact changing profiles of de novo HBV infection in Japan in relation to genotype and genomic variability are warranted.

Production and characterization of recombinant human anti-HBs Fab antibodies

Recombinant human Fab antibodies were generated with different reactivities against the hepatitis B virus surface (HBs) antigen. To isolate the antibodies, a method was used that combined transformation of human B cells by Epstein-Barr virus (EBV) infection with a primer-vector system developed for isolating DNA fragments of human Ig Fab portions. With this method, monoclonal and oligoclonal cell lines producing anti-HBs antibodies were established and three anti-HBs Fab antibodies were isolated from two of these cell lines. From analysis of affinity characteristics, immunohistochemical activity, and cytolysis activity, these three Fab antibodies were classified into three different groups. The first group had high affinity for HBs, the second had the ability to kill HBV-infected cells, and the third was applicable to immunohistochemical staining with HBV-infected cells. The combined effect of these antibodies was also investigated by complement-dependent cytotoxicity assay.

Characterization of seven genotypes (A to E, G and H) of hepatitis B virus recovered from Japanese patients infected with human immunodeficiency virus type 1

To investigate the prevalence of hepatitis B virus (HBV) genotypes and characteristics of HBV isolates among Japanese patients infected with human immunodeficiency virus type 1 (HIV), serum samples collected between September 1990 and March 2002 from 471 HIV-infected patients (age, 38.8 +/- 11.4 [mean +/- standard deviation] years; male, 90%) were tested for hepatitis B surface antigen (HBsAg) and HBV DNA. Positivity for HBsAg and HBV DNA was seen in 42 patients (8.9%), 41 of whom had contracted HIV infection through sexual activity and 1 had hemophilia. Genotypes of HBV were determined by comparative and phylogenetic analyses of the S gene sequence (396 nucleotides [nt]). The distribution of HBV genotypes among the 42 HBV-viremic patients was: A (50%), B (5%), C (24%), D (5%), E (2%), H (10%), A plus D (2%), A plus G (2%). The hemophilia patient had HBV genotype D. Genotypes E, G, and H which had not been reported in Japan, were found in one patient each who had traveled to Zambia, the US, and South America, respectively. Genotypes A and D, which are rare in Japan, were found in patients who had no history of traveling abroad. The entire genome of the HB-JI411 (genotype E [3,212 nt]), HB-JI444G (genotype G [3,248 nt]), and HB-JI260 (genotype H [3,218 nt]) isolates had the highest identity of 98.3%, 99.9%, and 98.5%, respectively, with reported HBV isolates of the same genotype. Most Japanese patients coinfected with HIV and HBV had HBV genotypes that are found rarely or had not been reported in Japan.

Epidemiology and management of infectious diseases in international adoptees

International adoptees represent a group of children with unique health care needs. Data from published studies, along with the recent experience of the Yale International Adoption Clinic, suggest that the risk of serious infections in adoptees is low, although infections associated with institutionalization still occur commonly. Interpretation of these data must be undertaken with caution, however, since many, if not most, international adoptees are not evaluated in specialty clinics. Thus, prospective studies designed to minimize selection and referral bias are needed in order to accurately define the risk of infectious and noninfectious diseases in all international adoptees.

Chronic hepatitis B: a long-term retrospective cohort study of disease progression in Shanghai, China

BACKGROUND AND AIMS

The present study aimed to describe the disease progression of chronic hepatitis B patients without or with compensated cirrhosis at baseline, to estimate the risk of progression to decompensated cirrhosis, hepatocellular carcinoma and death, and to determine prognostic factors of disease progression in patients in Shanghai, China.

METHODS

Stored medical records from 322 biopsy-confirmed chronic hepatitis B cases diagnosed between 1981 and 1993 were selected, and the status of patients was tracked in 1999-2000. Among consenting patients, ultrasound examination and laboratory tests were conducted. Person-year incidence rates, Kaplan-Meier analysis, log-rank tests, and Cox regression analysis were conducted.

RESULTS

Among chronic hepatitis B patients without compensated cirrhosis, the incidence rates of decompensated cirrhosis, hepatocellular carcinoma, and death were 6.3, 2.8, and 7.6 per 1000 person-years, respectively, while for patients with compensated cirrhosis, the rates were 35.6, 8.2, and 35.2 per 1000 person-years, respectively. The 15-year survival rate was 88% for patients without compensated cirrhosis, compared with 56% for patients with compensated cirrhosis (P < 0.001). Cox regression analysis demonstrated that increased alpha-fetoprotein (AFP) (P < 0.01), gamma-globulin (P < 0.05), and high-level severity of hepatic fibrosis (P < 0.01) at baseline were risk factors of decompensated cirrhosis. Factors associated with a high risk of death included elevated AFP at baseline (P < 0.01), severity of hepatic fibrosis (P < 0.003), and sustained positivity for hepatitis B surface antigen (P < 0.004).

CONCLUSION

Increased AFP and severity of hepatic fibrosis at baseline were associated with higher risk of decompensated cirrhosis and death. These data provide rare empirical estimates of the negative long-term outcomes for patients with chronic hepatitis B in Shanghai, China.

Combined passive and active immunoprophylaxis for preventing perinatal transmission of the hepatitis B virus carrier state in Shizuoka, Japan during 1980-1994

BACKGROUND

Efficacy and limits in preventing perinatal infection with hepatitis B virus (HBV) have been examined in a model area in Japan.

METHODS

In Shizuoka (population of 3.6 million), immunoprophylaxis of perinatal HBV infection was started in 1980 in four institutions (Hamamatsu Medical College, Shimada City Hospital, Shizuoka Kodomo Hospital and Numazu City Hospital). Babies born to carrier mothers with hepatitis B e antigen (HBeAg) in serum received hepatitis B immune globulins at birth and 2 months thereafter and vaccines at 2, 3 and 5 months after birth.

RESULTS

Overall, 980 of the 1030 babies born to HBeAg-positive carrier mothers were protected by the immunoprophylaxis during the 15 years from 1980 to 1994 with an efficacy of 95.1%. From 1986 to 1994 while the national immunoprophylaxis was conducted, 329,674 of the 346,637 (95.1%) expectant mothers were tested, and 2081 (0.63%) of them were positive for hepatitis B surface antigen (HBsAg). The immunoprophylaxis was given only to babies born to 764 (36.7%) of the 2081 mothers who tested positive for HBeAg. Of the 494 babies receiving immunoprophylaxis, in whom HBsAg was followed monthly after birth, 462 (93.5%) were protected. The HBV carrier state developed in the remaining 32 (6.5%) babies, 10 of whom (31.3% of the 32) turned positive for HBsAg within 1 month after birth, most likely owing to infection in utero.

CONCLUSIONS

Passive-active immunoprophylasxis of high-risk babies was highly efficacious in preventing perinatal transmission of the HBV carrier state. Most failures (approximately 70%) occurred in the high-risk babies who were exposed to HBV after birth, and would have been avoided by careful and extensive execution of the immunoprophylaxis.

Interruption of HBV intrauterine transmission: A clinical study

AIM: To investigate the effect of hepatitis B virus (HBV) specific immunoglobin (HBIG) and lamivudine on HBV intrauterine transmission in HBsAg positive pregnant women.

METHODS: Each subject in the HBIG group (56 cases) was given 200 IU HBIG intramuscularly (im.) every 4 wk from 28-week (wk) of gestation, while each subject in the lamivudine group (43 cases) received 100 mg lamivudine orally (po.) every day from 28-wk of gestation until the 30^th day after labor. Subjects in the control group (52 cases) received no specific treatment. Blood specimens were tested for HBsAg, HBeAg, and HBV-DNA in all maternities at 28-wk of gestation, before delivery, and in their newborns 24 h before the administration of immune prophylaxis.

RESULTS: Reductions of HBV DNA in both treatments were significant (P < 0.05). The rate of neonatal intrauterine HBV infection was significantly lower in HBIG group (16.1%) and lamivudine group (16.3%) compared with control group (32.7%) (P < 0.05), but there was no significant difference between HBIG group and lamivudine group (P > 0.05). No side effects were found in all the pregnant women or their newborns.

CONCLUSION: The risk of HBV intrauterine infection can be effectively reduced by administration of HBIG or Lamivudine in the 3^rd trimester of HBsAg positive pregnant women.

[Hepatitis viruses: mother to child transmission]

The infection by the hepatitis viruses, when appearing during the pregnancy, could result in damages for the infant. However, risks differ according to the implicated virus. Hepatitis B virus infection, for which prevalence varies according to areas, is injurious when the mother is chronic HBsAg carrier. Risk consists of neonate's contamination during the labour, and if contaminated, the neonate becomes a chronic carrier himself in 80 to 90% of cases. When the mother is positive for viral DNA in her serum, transmission rate is estimated at 90%. In the opposite, if the mother is negative for viral DNA in the serum, transmission rate is about 10 to 30%. HBsAg screening is obligatory in France during the sixth month of pregnancy: in case of positivity, serovaccination of the neonate is systematically carried out. Protection rate is 100% if the mother had a low viral load (<150 pg/ml) at the end of pregnancy, and weaker (about 70%) if the mother had a higher level of viral DNA. Transmission risk of hepatitis C virus (HCV) is much lesser, since it is about 5% for a woman who is positive for viral RNA at the end of her pregnancy, and at least 10% if the woman is moreover positive for the HIV. Risk is more important if the woman had an important plasmatic viral load (> 10(5) copies/ml) and if the duration between membrane rupture and delivery is long. Vaginal delivery and breast-feeding are not advised. Neonates from mothers who replicate the HCV at the end of pregnancy are serologically evaluated until 12-15 months of age, in order to determine their possible contamination.Delta virus transmission from mother to infant is exceptional and could be avoided by the HBV serovaccination of the new-born.Intra-utero transmission of hepatitis A virus is very rare, but perinatal transmission could occur. Materno-fetal transmission of hepatitis E virus has been reported, but the virus is essentially dangerous for the mother, resulting in a mortality rate of 15 to 25% if the acute infection occurs during the third trimester of the pregnancy.