Virologic factors associated with failure to passive-active immunoprophylaxis in infants born to HBsAg-positive mothers

Cost-effectiveness of tenofovir disoproxil fumarate prophylaxis for perinatal hepatitis B virus prevention in Ethiopia: a decision analytical modeling

BACKGROUND

Perinatal transmission of hepatitis B virus (HBV) remains a significant public health issue. To complement vaccination, tenofovir disoproxil fumarate (TDF) prophylaxis is recommended for HBV-infected pregnant women. We aimed to identify a cost-effective strategy for using TDF to prevent perinatal HBV transmission in Ethiopia.

METHODS

A decision tree combined with a Markov model was used to determine the cost-effectiveness of different strategies for preventing perinatal transmission of HBV in a cohort of 10,000 hepatitis B surface antigen (HBsAg)-positive pregnant women. The existing vaccination strategy (Strategy 1) was compared with three alternative strategies that added TDF prophylaxis to the existing strategy. Strategy 2 (TDF prophylaxis following HBV viral load testing), Strategy 3 (TDF prophylaxis following hepatitis B envelope antigen (HBeAg) testing), and Strategy 4 (TDF prophylaxis for all HBsAg-positive). Costs were measured from the healthcare sector perspective. Effects were measured as HBV infection averted and disability adjusted life years (DALYs) averted. Model input parameters were obtained from the literature review and local data. Cost-effectiveness was determined by the incremental cost-effectiveness ratio (ICER), with thresholds set at 0.34, 1, and 3 times the GDP per capita of Ethiopia. A sensitivity analysis was conducted to test the robustness of the results.

RESULTS

Among the alternatives, Strategy 4 is the most cost-effective strategy, with an ICER of 220.3 US$ per DALY averted. Strategy 4 would prevent 267 perinatal HBV infections and averted 1048 DALYs per 10,000 HBsAg-positive pregnant women. These results were robust to a range of parameters and showed a 97% probability of being cost-effective at one times the GDP per capita of Ethiopia. The next optimal strategy is Strategy 2, compared with the next best alternative, with an ICER of 1175.52 US$ per DALY averted. Strategy 3 was dominated by the available strategies.

CONCLUSION

Providing TDF prophylaxis for all HBsAg-positive pregnant women starting at 28 weeks of pregnancy has the potential to be a cost-effective strategy in Ethiopia. Introduction of TDF prophylaxis for all HBsAg-positive pregnant women is highly recommended, along with efforts to improve vaccination coverage.

Vertical Transmission in Mothers Taking TAF With Exceptionally High Viral Load

Published studies on tenofovir alafenamide (TAF) therapy for preventing vertical transmission of hepatitis B virus (HBV) have primarily enrolled mothers with viremic levels of approximately 7 log10 IU/mL. This study aimed to evaluate the efficacy and safety of TAF therapy in preventing mother-to-child transmission (MTCT) in mothers with exceptionally high viral loads, defined as HBV DNA levels > 2,000,000 IU/mL. Hepatitis B e antigen (HBeAg)-positive mothers with HBV DNA levels > 2,000,000 IU/mL were prospectively enrolled from four hospitals and initiated on TAF therapy between gestational weeks 26 and 28, continuing until delivery. All infants received immunoprophylaxis and were followed up to 28 weeks postpartum. The primary endpoints were the MTCT rate and the occurrence of congenital abnormalities in infants. Secondary outcomes included maternal HBV suppression at delivery and the safety of both mothers and infants. Among 137 mothers screened, 120 were enrolled in TAF therapy, and 121 infants completed the study. At delivery, 93.3% (112/120) of mothers achieved HBV DNA levels < 200,000 IU/mL. At birth, 0.8% (1/121) of infants had a congenital malformation, and 9.9% (12/121) tested positive for HBsAg. The vertical transmission rate was 2% (2/121, intention-to-treat) at 28 weeks of age. No severe adverse effects were reported in mothers or infants. On-treatment and postpartum alanine aminotransferase (ALT) flares after TAF cessation occurred in 7.5% (9/120) and 41.1% (46/112) of mothers, respectively, alongside viral rebound after cessation. Infant physical development remained within normal ranges based on national reference standards. In summary, approximately 2% of mothers on TAF therapy during late pregnancy experienced MTCT, despite proper immunoprophylaxis for their infants. Extending the treatment duration beyond 12 weeks for mothers with extremely high viral loads is recommended to improve MTCT prevention. No safety concerns were observed for either mothers or infants. Trial Registration: ClinicalTrials.gov identifier: NCT04237376.

Tenofovir and Hepatitis B Virus Transmission During Pregnancy: A Randomized Clinical Trial

Importance

Standard care for preventing mother-to-child transmission (MTCT) of hepatitis B virus (HBV) in highly viremic mothers consists of maternal antiviral prophylaxis beginning at gestational week 28 combined with an HBV vaccine series and HBV immune globulin (HBIG) at birth. However, HBIG is unavailable in some resource-limited areas.

Objective

To determine whether initiating tenofovir disoproxil fumarate (TDF) at gestational week 16 combined with HBV vaccinations for infants is noninferior to the standard care of TDF at gestational week 28 combined with HBV vaccinations and HBIG for infants in preventing MTCT in mothers with HBV and high levels of viremia.

Design, Setting, and Participants

An unblinded, 2-group, randomized, noninferiority clinical trial was conducted in 7 tertiary care hospitals in China. A total of 280 pregnant individuals (who all identified as women) with HBV DNA levels greater than 200 000 IU/mL were enrolled between June 4, 2018, and February 8, 2021. The final follow-up occurred on March 1, 2022.

Interventions

Pregnant individuals were randomly assigned to receive either TDF starting at gestational week 16 with HBV vaccinations for the infant or TDF starting at gestational week 28 with HBV vaccinations and HBIG administered to the infant.

Main Outcomes and Measures

The primary outcome was the MTCT rate, defined as detectable HBV DNA greater than 20 IU/mL or hepatitis B surface antigen positivity in infants at age 28 weeks. Noninferiority was established if the MTCT rate in the experimental group did not increase by more than an absolute difference of 3% compared with the standard care group, as measured by the upper limit of the 2-sided 90% CI.

Results

Among 280 pregnant individuals who enrolled in the trial (mean age, 28 years; mean gestational age at enrollment, 16 weeks), 265 (95%) completed the study. Among all live-born infants, using the last observation carried forward, the MTCT rate was 0.76% (1/131) in the experimental group and 0% (0/142) in the standard care group. In the per-protocol analysis, the MTCT rate was 0% (0/124) in the experimental group and 0% (0/141) in the standard care group. The between-group difference was 0.76% (upper limit of the 2-sided 90% CI, 1.74%) in all live-born infants and 0% (upper limit of the 2-sided 90% CI, 1.43%) in the per-protocol analysis. Both comparisons met the criterion for noninferiority. Rates of congenital defects and malformations were 2.3% (3/131) in the experimental group and 6.3% (9/142) in the standard care group (difference, 4% [2-sided 95% CI, -8.8% to 0.7%]).

Conclusions and Relevance

Among pregnant women with HBV and high levels of viremia, TDF beginning at gestational week 16 combined with HBV vaccination for infants was noninferior to the standard care of TDF beginning at gestational week 28 combined with HBIG and HBV vaccination for infants. These results support beginning TDF at gestational week 16 combined with infant HBV vaccine to prevent MTCT of HBV in geographic areas where HBIG is not available.

Trial Registration

ClinicalTrials.gov Identifier: NCT03476083.

Update on the treatment navigation for functional cure of chronic hepatitis B: Expert consensus 2.0

As new evidence emerges, treatment strategies toward the functional cure of chronic hepatitis B are evolving. In 2019, a panel of national hepatologists published a Consensus Statement on the functional cure of chronic hepatitis B. Currently, an international group of hepatologists has been assembled to evaluate research since the publication of the original consensus, and to collaboratively develop the updated statements. The 2.0 Consensus was aimed to update the original consensus with the latest available studies, and provide a comprehensive overview of the current relevant scientific literatures regarding functional cure of hepatitis B, with a particular focus on issues that are not yet fully clarified. These cover the definition of functional cure of hepatitis B, its mechanisms and barriers, the effective strategies and treatment roadmap to achieve this endpoint, in particular new surrogate biomarkers used to measure efficacy or to predict response, and the appropriate approach to pursuing a functional cure in special populations, the development of emerging antivirals and immunomodulators with potential for curing hepatitis B. The statements are primarily intended to offer international guidance for clinicians in their practice to enhance the functional cure rate of chronic hepatitis B.

Patient-reported outcomes in mothers with chronic hepatitis B infection: A cross-sectional analysis

BACKGROUND & AIMS

The health-related quality of life (HRQoL) during pregnancy has not been well-lidated in mothers with chronic hepatitis B (CHB). We aim to compare patient-reported outcomes (PROs) in CHB mothers with those of healthy mothers during pregnancy.

METHODS

Between 4/16/2023 and 7/31/2023, we invited consecutive CHB and healthy mothers to complete the self-administered 36-item Short Form Survey (SF-36) and the Chronic Liver Disease Questionnaire (CLDQ) for PRO assessment. Pairwise comparisons of PRO scores between groups were performed using chi-square tests. Covariates for worse PROs were further analyzed by the multiple linear regression model to identify the independent predictors RESULTS: Among 257 participants (CHB: healthy control was 100:157), the mean (SD) age was 29.6 (3.4), and the majority completed the PRO assessment at the gestational weeks of 16-24. When compared to healthy mothers, CHB mothers had a significant impairment of PROs in the CLDQ domain of worry (6.97±0.16 vs 5.83±0.99, p<0.05) and the SF-36 domain of social functioning (95.33±10.00 vs 91.67±16.37, p<0.05). The subgroup analyses in CHB mothers showed HBV DNA >200,000 IU/mL associated with significantly worse PROs. The multivariate analyses identified CHB infection, severe nausea or vomiting, poor living conditions, and spousal negative attitude as independent predictors of HRQoL impairment.

CONCLUSION

This study suggests that CHB infection during pregnancy negatively impacted HRQoL, particularly in worry and social functioning domains. CHB infection was an independent predictor for PRO impairments. Further integration of monitoring and intervention on HRQoL impairment should be considered when managing CHB mothers during pregnancy.

A prospective, multicenter study of hepatitis B birth-dose vaccine with or without hepatitis B immunoglobulin in preventing mother-to-child transmission of hepatitis B virus in Ethiopia

BACKGROUND

Historically, mother-to-child transmission (MTCT) of hepatitis B virus (HBV) was considered uncommon in Africa, leading to a reluctant attitude to birth-dose HBV vaccination on the continent. As a randomized trial would be unethical, real-life data are needed to assess the effect of HBV birth-dose vaccine in Africa.

METHODS

A multicenter, prospective, observational study of hepatitis B surface antigen (HBsAg)-positive pregnant women and their infants was carried out in Ethiopia, from January 2019 to May 2021. Pregnant women were screened for HBsAg and HIV as part of routine antenatal care and/or delivery, and HBsAg-positive HIV-negative pregnant women were included in the study. HBV birth-dose vaccine and hepatitis B immunoglobulin (HBIg) were recommended but not all newborns received it as it was not national policy. All infants, however, received the pentavalent HBV vaccine at 6, 10, and 14 weeks of age. Vaccination status was confirmed from delivery ward charts and infant vaccination certificates. Infants were tested for HBsAg at 9 months of age and a positive result was taken as evidence of MTCT.

FINDINGS

Of 290 HBsAg-positive pregnant women, 168 mother/infant pairs returned for their 9-month follow-up visit and were included in this analysis. Two of 112 (1.8 %) infants who received birth-dose vaccine with HBIg, and 2 of 23 (8.7 %) who received birth-dose vaccine alone were HBsAg positive at nine months of age, compared to 8 of 33 (24.2 %) who received neither vaccine nor HBIg at birth (p = 0.002). High maternal viral load (>200,000 IU/ml; adjusted odds ratio [AOR] 10.4; 95 % confidence interval [CI] 1.2-92.1) and not receiving HBV birth-dose vaccine nor HBIg (AOR 29.2; 95 % CI 4.0-211.3) were independent predictors of MTCT.

INTERPRETATION

Birth-dose HBV vaccine with or without HBIg significantly reduced the risk of MTCT of HBV in Ethiopia. Improved coverage of birth-dose HBV vaccine should be an urgent priority.

Congenital and Perinatal Viral Infections: Consequences for the Mother and Fetus

Viruses are the most common congenital infections in humans and an important cause of foetal malformations, neonatal morbidity, and mortality. The effects of these infections, which are transmitted in utero (transplacentally), during childbirth or in the puerperium depend on the timing of the infections. These vary from miscarriages (usually with infections in very early pregnancy), congenital malformations (when the infections occur during organogenesis) and morbidity (with infections occurring late in pregnancy, during childbirth or after delivery). The most common of these viruses are cytomegalovirus, hepatitis, herpes simplex type-2, parvovirus B19, rubella, varicella zoster and zika viruses. There are currently very few efficacious antiviral agents licensed for use in pregnancy. For most of these infections, therefore, prevention is mainly by vaccination (where there is a vaccine). The administration of immunoglobulins to those exposed to the virus to offer passive immunity or appropriate measures to avoid being infected would be options to minimise the infections and their consequences. In this review, we discuss some of the congenital and perinatal infections and their consequences on both the mother and fetus and their management focusing mainly on prevention.

Tenofovir Alafenamide Versus Tenofovir Disoproxil Fumarate for Preventing Vertical Transmission in Chronic Hepatitis B Mothers: A Systematic Review and Meta-Analysis

OBJECTIVE

International guidelines recommend maternal tenofovir disoproxil fumarate (TDF) therapy accompanied by infant immunoprophylaxis to prevent hepatitis B virus (HBV) mother-to-child transmission (MTCT) in highly viremic mothers. However, pooled analyses for tenofovir alafenamide (TAF) effects and comparisons between the 2 regimens are lacking.

DESIGN

In this meta-analysis, pairs of independent reviewers performed multiple database searches from inception to 31 March 2024 and extracted data from cohort studies and randomized controlled trials (RCTs) in highly viremic mothers. The outcomes of interest were the reduction of MTCT and safety in the TDF-treated, TAF-treated, and control groups.

RESULTS

We included 31 studies with 2588 highly viremic mothers receiving TDF, 280 receiving TAF, and 1600 receiving no treatment. Compared to the control, TDF therapy reduced the MTCT rate in infants aged 6-12 months (risk ratio: 0.10, 95% confidence interval [CI] .07-.16). Pairwise meta-analysis between TAF and TDF revealed similar effects on reducing MTCT (risk ratio: 1.09, 95% confidence interval .16-7.61). Network meta-analysis showed equal efficacy of the 2 regimens in reducing MTCT (risk ratio: 1.09, 95% CI .15-7.65). The surface under the cumulative ranking curve revealed TDF as the best regimen compared with TAF (probability ranking: .77 vs .72), while receiving a placebo during pregnancy had the lowest efficacy (probability ranking 0.01). There were no safety concerns for mothers and infants in all regimens.

CONCLUSIONS

Compared to placebo or no treatment, maternal TDF and TAF prophylaxis are equally effective and without safety concerns in reducing MTCT in highly viremic mothers.

The effect of intrahepatic cholestasis in pregnancy combined with different stages of hepatitis B virus infection on pregnancy outcomes: a retrospective study

BACKGROUND AND AIMS

To investigate the impact of intrahepatic cholestasis of pregnancy (ICP) with hepatitis B virus (HBV) infection on pregnancy outcomes.

METHODS

We selected 512 pregnant women, collected the data including maternal demographics, main adverse pregnancy outcomes and maternal HBV infected markers HBeAg and HBV-DNA loads status, then have a comparative analysis.

RESULTS

There were 319 solitary ICP patients without HBV infection (Group I) and 193 ICP patients with HBV infection. Of the latter, there were 118 cases with abnormal liver function(Group II) and 80 cases with normal liver function(Group III). All HBV-infected pregnant women with ICP were divided into hepatitis Be antigen (HBeAg)-positive group (102 cases) and HBeAg-negative group (91 cases), according to the level of the serum HBeAg status; and into high viral load group (92 cases), moderate viral load group (46 cases) and low viral load group (55 cases) according to the maternal HBV-DNA level. Group II had a higher level of serum total bile acids, transaminase, bilirubin as well as a higher percentage of premature delivery, neonatal intensive care unit (NICU) admission and meconium-stained amniotic fluid (MSAF) compared with the other two groups(P < 0.05), but there were no significant differences in the above indicators between the Group I and Group III. Among the HBV-infected patients with ICP, HBeAg-positive group had a higher level of serum transaminase, bilirubin and bile acid as well as earlier gestational weeks of delivery, lower birth weight of new-borns and a higher rate of NICU admission than HBeAg-negative group (P < 0.05). Those with a high viral load (HBV-DNA > 106 IU/ml) had a higher level of transaminase, bilirubin, and bile acid as well as shorter gestational weeks of delivery, lower birth weight of new-borns and a higher rate of NICU admission compared with those with a low or moderate viral load (P < 0.05).

CONCLUSION

HBV-infected pregnant women with ICP combined with abnormal liver function have more severe liver damage, a higher percentage of preterm birth and NICU admission. HBeAg-positive status and a high HBV-DNA load will increase the severity of conditions in HBV-infected pregnant women with ICP. HBV-infected patients with ICP who have abnormal liver function, HBeAg-positive or a high viral load should be treated more actively.

Analysis of Serum Anti-HBs Levels and HBsAg/HBeAg Markers in Children and Adolescents: A Cross-Sectional Study

Hepatitis B virus (HBV) is a global public health concern, and China continues to face a high burden of HBV cases. Vaccination plays a critical role in controlling and eradicating HBV. However, studies have shown that some individuals may experience waning immunity over time, highlighting the importance of enhanced immunization strategies. This study aimed to investigate the relationship between age, gender, and anti-HBs antibody levels, as well as the prevalence of serum hepatitis B surface antigen (HBsAg)/HBV e antigen (HBeAg) positivity. This retrospective study included 43,609 pediatric patients who visited the outpatient department between January 2013 and December 2022. Serum biomarkers (HBsAg, anti-HBs, HBeAg, anti-HBe, and anti-HBc) were measured using Roche Cobas 8000. There is a significant difference in anti-HBs titer between genders and across different age groups (p < 0.05). The serological markers HBsAg/HBeAg exhibited the highest positivity rate in the age group of 15-18 years. The findings demonstrate a gradual decrease in anti-HBs levels following HBV vaccination. The prevalence of serum markers HBsAg/HBeAg is higher among adolescents aged 15-18 years, which should be a matter of concern and attention.

Change in Prevalence of Hepatitis B Virus Infection in Pregnant Women in the Last Two Decades in Thailand

Objectives: In Thailand, there has been a strategy to prevent the mother-to-child transmission of HBV for over 30 years. However, there is still a lack of empirical evidence regarding the effectiveness of this strategy. This study aims to investigate the trends in the prevalence of HBV infection in pregnant women and to identify factors that may be associated with the prevalence of HBV infection in pregnant women. Patients and Methods: A maternal-fetal medicine database was accessed to retrieve the consecutive obstetric records of women giving birth at Chiang Mai University Hospital, Thailand, from January 2003 to December 2022. All women undergoing HBV tests with available results were included for an analysis of the trends and changes in the prevalence of maternal HBV infection. Also, the rates of infection in different age cohorts were compared. Results: During the study period, a total of 36,958 women were eligible for analysis. Overall, the prevalence of HBV infection in pregnant women was found to be 5.3% (1970 cases). Overall, HBV prevalence fell from 6.11% in 2003 to 3.15% in 2022. There was a significant reduction, especially in the adolescent group, decreasing from 8.26% in 2003 to 0% in 2022. In the reproductive age group, the prevalence significantly decreased from 6.41% to 2.01%. However, the prevalence in the elderly group was unchanged. The only significant risk factor was the years in the early timeline of the study period, presumably associated with previous HBV vaccination. Other factors, such as socioeconomic status, residential area, and being a private case, were not correlated with the prevalence of HBV. Conclusion: The prevalence of HBV infection in pregnant women has significantly decreased in the past two decades from 6.11% in 2003 to 3.15% in 2022. The percentage of reduction was very striking in the adolescent group, dropping from 8.6% in 2003 to 0.0% in 2022 or being nearly eradicated in the most recent years. Our results suggest that the overall prevalence of HBV infection among our pregnant women will probably be less than 1.0% in the near future.

Role of HBsAg levels in guiding hepatitis B virus prophylaxis in pregnancy: Insights from a multi-ethnic cohort

Pregnant mothers with chronic hepatitis B infection (CHB) need peri-partum antiviral prophylaxis (PAP) to reduce the risk of mother-to-child-transmission. Currently, PAP is recommended in those with high viral load (VL) that is, HBV DNA >200,000 IU/mL. Quantitative hepatitis B surface antigen (qHBsAg) >10,000 IU/mL, a cut-off derived primarily from hepatitis B e-antigen (HBeAg) positive antenatal cohorts in Chinese populations, is advocated as a surrogate marker of VL for guiding PAP. We investigated the utility of qHBsAg to predict high-VL in a multi-ethnic urban cohort with CHB. A consecutive cohort of women with CHB was identified from Barts Health NHS Trust databases in the United Kingdom. We included women with paired HBV DNA and qHBsAg during pregnancy. Women already on antiviral at conception were excluded. A total of 769 pregnancies in 678 CHB pregnant mothers (median age 31 years-old, 8.6% HBeAg+) were included. At median gestational age of 15.3 weeks, HBV DNA was 336 (IQR 44-2998) IU/mL, with 65 (8.5%) being high-VL. Serum qHBsAg was most useful in Black/Black-British/Caribbean/African (AUROC 0.946) with 100% sensitivity and 80.6% specificity to predict high-VL; but it performed less well for other ethnicities: Asian (AUROC 0.877), White (AUROC 0.797) and mixed ethnicities (AUROC 0.742). In conclusion, for settings where healthcare resources are not limited, HBV DNA remains the optimal marker to identify highly viraemic pregnancies for guiding PAP. For resource-limited settings where the prevailing cost is treatment, serum qHBsAg can be used in Black/Black British/Caribbean/African sub-cohorts, but not for other ethnicities.

Maternal-to-Child Transmission of Hepatitis B Virus and Hepatitis Delta Virus

Maternal-to-child transmission of hepatitis B virus (HBV) and hepatitis delta virus (HDV) can lead to the risk of progressive liver disease in infants, but fortunately effective interventions exist to decrease transmission. Counseling on the risk of maternal-to-child transmission, care pathways to decrease transmission, and the implications of HBV and HDV on pregnancy outcomes are the key components of caring for pregnant people living with HBV and HDV.

EASL Clinical Practice Guidelines on the management of liver diseases in pregnancy

Liver diseases in pregnancy comprise both gestational liver disorders and acute and chronic hepatic disorders occurring coincidentally in pregnancy. Whether related to pregnancy or pre-existing, liver diseases in pregnancy are associated with a significant risk of maternal and fetal morbidity and mortality. Thus, the European Association for the Study of Liver Disease invited a panel of experts to develop clinical practice guidelines aimed at providing recommendations, based on the best available evidence, for the management of liver disease in pregnancy for hepatologists, gastroenterologists, obstetric physicians, general physicians, obstetricians, specialists in training and other healthcare professionals who provide care for this patient population.

Possible Association between Genetic Diversity of Hepatitis B Virus and Its Effect on the Detection Rate of Hepatitis B Virus DNA in the Placenta and Fetus

Background: The prevalence of HBV infection and HBV genotypes varies from country to country, and the role of HBV genotypes in the presence of HBV in the placenta and fetus has never been explored. This study was conducted to (1) identify HBV genotypes, and their frequencies, that infected Northern Thai pregnant women; (2) evaluate the association between HBV genotypes and the detection rate of HBV DNA in the placenta and fetus; (3) evaluate the association between specific mutations of the HBV genome and HBV DNA detection in placental tissue; and (4) identify the mutation of the HBV genome that might occur between maternal blood, placenta, and cord blood. Methods: Stored samples of the maternal blood, placental tissue, and cord blood that were collected from 145 HBsAg-positive pregnant Thai women were analyzed to identify HBV DNA. Results: Approximately 25% of infected mothers had fetal HBV DNA detection, including cases with concomitant HBV DNA detection in the placenta (77.3%). A total of 11.7% of cases with placental detection had no HBV DNA detection in the maternal blood, indicating that the placenta could be a site of HBV accumulation. Of the 31 HBV-positive blood samples detected by nested PCR, the detected strains were subgenotype C1 (77.4%), subgenotype B9 (9.7%), and subgenotype C2, B2, B4, and recombinant B4/C2 (3.2% for each). Genotype B had a trend in increased risk of placental HBV DNA detection compared to genotype C, with a relative risk of 1.40 (95% CI: 1.07-1.84). No specific point mutation had a significant effect on HBV DNA detection in placental tissue. Mutation of C454T tended to enhance HBV DNA detection in placental tissue, whereas T400A tended to have a lower detection rate. No mutation was detected in different sample types collected from the same cases. Conclusions: HBV DNA detection in the fetus was identified in approximately 25% of HBV-positive mothers, associated with the presence of HBV in the placenta in most cases. The placenta could possibly be a site of HBV accumulation. Subgenotype C1 was the most common subgenotype, followed by subgenotype B9. HBV genotype B possibly had a higher trend in intrauterine detection than HBV genotype C. Mutation is unlikely to occur during intrauterine exposure.

Enhancing interventions for prevention of mother-to-child- transmission of hepatitis B virus

Prevention of mother-to-child transmission of hepatitis B virus (HBV) infection is a cornerstone of efforts to support progress towards elimination of viral hepatitis. Current guidelines recommend maternal screening, antiviral therapy during the third trimester of high-risk pregnancies, universal and timely HBV birth dose vaccination, and post-exposure prophylaxis with hepatitis B immunoglobulin for selected neonates. However, serological and molecular diagnostic testing, treatment and HBV vaccination are not consistently deployed, particularly in many high endemicity settings, and models predict that global targets for reduction in paediatric incidence will not be met by 2030. In this article, we briefly summarise the evidence for current practice and use this as a basis to discuss areas in which prevention of mother-to-child transmission can potentially be enhanced. By reducing health inequities, enhancing pragmatic use of resources, filling data gaps, developing advocacy and education, and seeking consistent investment from multilateral agencies, significant advances can be made to further reduce vertical transmission events, with wide health, societal and economic benefits.

A Review of the Systemic Manifestations of Hepatitis B Virus Infection, Hepatitis D Virus, Hepatocellular Carcinoma, and Emerging Therapies

Chronic hepatitis B virus (HBV) infection affects about 262 million people worldwide, leading to over 820,000 deaths each year primarily due to cirrhosis and hepatocellular carcinoma. The World Health Organization has pledged to eliminate HBV as a health threat by 2030, but currently, no countries are on track to achieve this goal. One of the barriers to HBV elimination is stigma, causing shame, denial, self-isolation, self-rejection, and depression leading to those with chronic HBV less likely to get tested or seek treatment and more likely to conceal their infection. Other barriers include limited access to care and complicated and restrictive clinical practice guidelines. Increasing public and political efforts are necessary to raise awareness, increase access to care, and change screening and treatment guidelines. The current guidance of the American Association for the Study of Liver Diseases (AASLD) recommends testing only if patients are considered at risk, but this has proven to be ineffective. We propose a simplified "test all and treat all" approach with a 5-line guideline for HBV infection. Universal screening and treatment of adults is cost-effective and can prevent transmission by effectively managing chronic HBV. All patients who are hepatitis B surface antigen (HBsAg) positive with detectable HBV-DNA should receive treatment until HBsAg is undetectable for 12 months, as HBV-DNA transmission via blood transfusion can occur even at low viral loads of 16 copies/mL, and mother-to-child transmission is still a risk even with passive-active immunoprophylaxis. Furthermore, clinical outcomes after HBsAg clearance are significantly better than the clinical outcomes of those who remain HBsAg positive.

Effect of prophylactic antiviral intervention on T cell immunity in hepatitis B virus-infected pregnant women

BACKGROUND

Antiviral intervention in hepatitis B virus (HBV)-infected pregnant women can effectively reduce mother-to-child transmission. However, the immunological characteristics of pregnant women with chronic HBV infection and the effects of antiviral intervention during pregnancy on maternal immune response remain unknown. We aimed to investigate these effects by comparing mothers who received antiviral intervention during pregnancy with those who did not.

METHODS

Pregnant women positive for hepatitis B surface antigen and hepatitis B e-antigen (HBsAg⁺ HBeAg⁺) were enrolled at delivery, including 34 received prophylactic antiviral intervention during pregnancy (AVI mothers) and 15 did not (NAVI mothers). T lymphocyte phenotypes and functions were analysed using flow cytometry.

RESULTS

At delivery, maternal regulatory T cell (Treg) frequency in AVI mothers was significantly higher than that in NAVI mothers (P < 0.002), and CD4⁺ T cells in AVI mothers displayed a decreased ability to secrete IFN-γ (P = 0.005) and IL-21 (P = 0.043), but an increased ability to secrete IL-10 and IL-4 (P = 0.040 and P = 0.036), which represented a higher Treg frequency, enhanced Th2 response and suppressed Th1 response. Treg frequency among AVI mothers was correlated negatively with serum HBsAg and HBeAg levels. After delivery, the ability of CD4⁺ T cells or CD8⁺ T cells to secrete IFN-γ or IL-10 was similar and no significant difference in Treg frequency was found between the two groups.

CONCLUSIONS

Prophylactic antiviral intervention during pregnancy has an effect on T cell immunity in pregnant women, which was characterised by increased maternal Treg frequency, enhanced Th2 response and suppressed Th1 response at delivery.

Vertical Transmission of Hepatitis B Virus-An Update

Hepatitis B virus (HBV) infection is a major public health problem in the world. Approximately 296 million people are chronically infected. In endemic areas, vertical transmission is a common route of transmission. There are several strategies for the prevention of HBV vertical transmission, such as antiviral treatment during the third trimester of pregnancy and immunoprophylaxis to newborns that includes the administration of hepatitis B immune globulin (HBIG) and an HBV vaccine. Despite this, immunoprophylaxis failure can occur in up to 30% of infants born to HBeAg-positive mothers and/or with high viral load. Therefore, management and prevention of HBV vertical transmission is of paramount significance. In this article, we provided a review of the epidemiology, mechanisms of pathogenesis and risk factors of vertical transmission, as well as the strategies implemented to prevent the infection.

The Use of Tenofovir Disoproxil Fumarate and Tenofovir Alafenamide for Preventing Vertical Transmission of Hepatitis B

BACKGROUND

Mother-to-child transmission (MTCT) of hepatitis B virus may occur in highly viremic mothers despite the infants receiving appropriate immunoprophylaxis. We aimed to review tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) data for preventing MTCT.

METHODS AND DATA SELECTION

We performed a systematic review between January 1, 2015 and December 31, 2021 on PUBMED, EMBASE, Cochrane, CNKI, and Wanfang databases. Data was extracted from randomized controlled trials or cohort studies in English or Chinese. The outcomes of interest included the efficacy and safety of TDF versus TAF or TDF/TAF versus placebo for preventing MTCT (PROSPERO registration: CRD42021256656).

RESULTS

Data from forty-three studies (13 randomized controlled trials, 30 nonrandomized studies) were included in the review. All infants in the studies received appropriate immunoprophylaxis. Among 3656 highly viremic mothers treated with TDF, hepatitis B virus DNA suppression to the levels <200,000 IU/mL at delivery was achieved in 34% to 100% of mothers. MTCT rates were 0 to 5% and 2 to 83% in mothers treated with TDF and in those who received no treatment, respectively. Congenital malformation rates were 0 to 2.1% in the TDF groups, which did not differ from the nontreated groups. Similar findings were reported in 4 studies that enrolled 326 mothers for maternal TAF therapy, resulting in 0% of MTCT and 0% infant malformation. All studies observed that TDF or TAF maternal therapy reduced MTCT rates significantly without safety concerns when compared with untreated groups, except for 1 RCT that failed the therapeutic endpoint.

CONCLUSIONS

TDF is well established for preventing MTCT in highly viremic mothers, whereas TAF may become an option as data emerges.

Comparison of tenofovir disoproxil fumarate and telbivudine in preventing hepatitis B transmission in mothers with high viral load

OBJECTIVE

To add to the limited data that exist on the selection of drugs to prevent mother-to-child transmission (MTCT) of hepatitis B virus (HBV).

METHODS

This is a prospective cohort study that enrolled mothers with HBV-DNA ≥2 × 10⁵  IU/ml. All enrolled mothers received either tenofovir disoproxil fumarate (TDF) or telbivudine (LdT) to prevent HBV transmission.

RESULTS

A total of 270 mothers received TDF treatment and 275 mothers received LdT treatment. The predelivery decline in HBV-DNA in the TDF group was higher than the LdT group (3.92 ± 0.93 log IU/ml vs. 3.76 ± 0.94 log IU/ml, P = 0.043). In the primary analysis, the MTCT rate of the TDF group was comparable to that of the LdT group, both in the intention-to-treat analysis (1.5% [4/275] vs. 1.8% [5/273], P > 0.99) and the per-protocol analysis (0% in both groups, P > 0.99). The alanine aminotransferase elevation rates in the TDF group were lower than in the LdT group (17.3% vs. 27.4%, P = 0.005). Less anorexia and more arthralgia were observed in the LdT group than the TDF group.

CONCLUSIONS

TDF and LdT are both effective in preventing MTCT of HBV, but they may cause different adverse events. TDF is more effective in reducing HBV viral load and had fewer alanine aminotransferase abnormalities than LdT.

Infant immune response to hepatitis B vaccine after fetal exposure to telbivudine

Whether telbivudine (LdT) treatment to pregnant women with hepatitis B surface antigen (HBsAg) affects infant immune response to hepatitis B vaccine (HepB) has not been investigated. A total of 127 HBsAg positive mothers and their neonates were enrolled and followed up at 11–13 months. Mothers took LdT (LdT group) or did not receive antiviral therapy (control group). Infant anti-HBs, immune cells and cytokines were measured after HepB was administered according to 0-1-6 procedure. We performed a 1:3 propensity score matching (PSM). Immune indexes in the two groups were compared. Baseline characteristics of mother-baby pairs were comparable in LdT group and control group. Infant anti-HBs geometric mean concentration (GMC) did not differ significantly between the two groups [767.70 (745.35) vs. 711.90 (819.60), P = .599]. There was no difference between the two groups in infant positive rate of anti-HBs [97.8% (91/93) vs. 97.1% (33/34), P = .999] and strong positive rate of anti-HBs [40.9% (38/93) vs. 44.1% (15/34), P = .742]. Infants with negative, low, medium, and high anti-HBs levels were similarly distributed between the two groups (P = .511). No differences in proportion of helper T cells, cytotoxic T cells, B cells, myeloid dendritic cells, and plasmacytoid dendritic cells of infants (P > .05) were detected between the two groups. Children in the LdT and control group had comparable levels of interleukin-2, interleukin-4, interleukin-6, interleukin-10, interleukin-12, interferon-α, interferon-γ and tumor necrosis factor-α (P > .05). Intrauterine exposure to LdT was safe to infant immune response to HepB after birth.

Clinical characteristics of hepatitis flares during pregnancy and postpartum in Chinese chronic hepatitis B virus carriers-a prospective cohort study of 417 cases

BACKGROUND

In China, it is common for pregnant women with a high load of hepatitis B virus (HBV) to take nucleos(t)ide analogue (NA) to prevent maternal-to-child transmission of HBV. However, the impact of NA intervention on virological and biochemical parameters in pregnant and postpartum women and the safety of drug cessation remain unclear. A prospective observational cohort was established in this study to analyze the clinical characteristics of hepatitis flares in pregnant and postpartum chronic HBV carriers, with or without NA intervention.

METHODS

Pregnant women who were chronic HBV carriers were enrolled in this study and divided into an NA intervention group and a non-intervention group according to their preferences. Liver function, HBV DNA level, and HBV serological markers were regularly measured during pregnancy and at approximately 6 weeks, 12 weeks, 24 weeks, 36 weeks, and 48 weeks postpartum.

RESULTS

A total of 417 patients were enrolled, including 303 in the NA intervention group and 114 in the non-intervention group. The incidence rates of postpartum hepatitis flares in both groups were higher than that of during pregnancy (45.7% vs 10.9%, p < 0.001; 41.2% vs 17.7%, p < 0.001). The second trimester was the peak of the incidence of flares during pregnancy and the incidence peak of postpartum flares was about 6 weeks postpartum. A total of 98% (145/148) of postpartum flares occurred within 24 weeks postpartum. After drug cessation, the incidence rate of flares was 34.1% (44/129).

CONCLUSION

In pregnant chronic HBV carriers, a certain proportion of hepatitis flares occurred during pregnancy and postpartum regardless of whether NA intervention was used, and the incidence of postpartum flares (44.6%) was significantly higher than that (12.8%) of during pregnancy. The flare incidence peaked at approximately 6 weeks postpartum, which may be the time period suitable for treatment. Since 98% of postpartum flares occurred within 24 weeks postpartum, the follow-up after drug cessation should be at least 24 weeks postpartum.

Viral hepatitis in pregnancy

Viral hepatitis is caused by a heterogenous group of viral agents representing a wide range of phylogenetic groups. Many viruses can involve the liver and cause liver injury but only a subset are delineated as 'hepatitis viruses' based upon their primary site of replication and tropism for hepatocytes which make up the bulk of the liver cell population. Since their discovery, beginning with the agent that caused serum hepatitis in the 1960s, the alphabetic designations have been utilized. To date, we have five hepatitis viruses, A through E, though it is postulated that others may exist. This chapter will focus on those viruses. Note that hepatitis D is included as a subset of hepatitis B, as it cannot exist without concurrent hepatitis B infection. Pregnancy has the potential to affect all aspects of these viral agents due to the unique immunologic and physiologic changes that occur during and after the gestational period. In this review, we will discuss the most common viral hepatitis and their effects during pregnancy.

Low knowledge about hepatitis B prevention among pregnant women in Kinshasa, Democratic Republic of Congo

Infants infected perinatally with hepatitis B (HBV) are at the highest risk of developing chronic hepatitis and associated sequelae. Prevention of mother-to-child transmission (PMTCT) of HBV requires improved screening and awareness of the disease. This study evaluated existing HBV knowledge among pregnant mothers (n = 280) enrolled in two HBV studies in urban maternity centers in Kinshasa, Democratic Republic of the Congo. All mothers responded to three knowledge questions upon study enrollment. Baseline levels of knowledge related to HBV transmission, treatment, prevention, and symptoms were low across all participants: 68.8% did not know how HBV was transmitted, 70.7% did not know how to prevent or treat HBV MTCT, and 79.6% did not know signs and symptoms of HBV. Over half of participants responded "I don't know" to all questions. HBV-positive women who participated in both studies (n = 46) were asked the same questions during both studies and showed improved knowledge after screening and treatment, despite no formal educational component in either study (p < 0.001). These findings highlight the need for intensified education initiatives in highly endemic areas to improve PMTCT efforts.

Impaired CD8 T cells in term pregnancy decidua with chronic hepatitis B virus infection

PROBLEM

Hepatitis B virus (HBV) infection is more likely to develop a state of chronicity in early life, particularly mother-to-child transmission (MTCT) of HBV in the fetus during pregnancy. Till now, little is known about the impact of chronic HBV infection on the immune status of the maternal-fetus interface, and the immune profile of placental lymphocytes in MTCT of HBV is poorly understood.

METHOD OF STUDY

Thirteen term pregnant women with chronic HBV infection (HBV-PW) and thirteen normal pregnant women as healthy control (HC-PW) were enrolled. The profile of placental immune cells and paired peripheral blood were analyzed by flow cytometry and immunohistochemistry.

RESULTS

Compared with HC-PW, the frequency of CD8⁺ T cells from the term placenta of HBV-PW was significantly reduced. These cells showed decreased expression of activation molecules CD69 and HLA-DR; thus, decidual CD8⁺ T cells from HBV-PW demonstrated hypofunctional signature as evidenced by significantly reduced production of IFN-γ, as well as compromised ability of degranulation and proliferation.

CONCLUSIONS

These findings supported that hypoactivated decidual CD8⁺ T cells might possess compromised ability in chronically HBV-infected term pregnant women. Our study provides robust evidence for the necessity and importance of antiviral intervention in HBV-PW to prevent MTCT of HBV. This article is protected by copyright. All rights reserved.

Immunoglobulin-free strategy to prevent HBV mother-to-child transmission in Cambodia (TA-PROHM): a single-arm, multicentre, phase 4 trial

BACKGROUND

Prevention of mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is based on administration of vaccine and immunoglobulins (HBIg) to newborns at birth and maternal antiviral prophylaxis for those with an HBV-DNA viral load of at 5·3 log₁₀ IU/mL or more. Many low-income and middle-income countries face difficulty in accessing HBIg and HBV-DNA quantification. The aim of this study was to evaluate the effectiveness of an HBIg-free strategy to prevent MTCT of HBV.

METHODS

TA-PROHM was a single-arm, multicentre, phase 4 trial done in five maternity units in Cambodia. Pregnant women who were positive for hepatitis B surface antigen (HBsAg), aged 18 years or older were included. Women who were HCV or HIV positive, had creatinine clearance of less than 30 mL/min, severe gravid disease, and planned to give birth outside the study sites were excluded. From Oct 4, 2017, to Jan 9, 2019, HBsAg positive pregnant women who tested positive for hepatitis B e antigen (HBeAg) with a rapid diagnostic test were eligible to receive tenofovir disoproxil fumarate. From Jan 9, 2019, women who were HBeAg negative with an alanine aminotransferase concentration of ≥40 IU/L were also eligible to receive tenofovir disoproxil fumarate. Women in the tenofovir disoproxil fumarate eligible group received 300 mg of tenofovir disoproxil fumarate orally once a day from the 24th week of gestation until 6 weeks postpartum. The primary outcome was the overall proportion of infants who were HBsAg positive at 6 months of life, confirmed by positive HBV DNA quantification. For the primary outcome, the proportion (95% CI) of infants with HBsAg at 6 months was stratified according to infant's HBIg status, duration of maternal tenofovir disoproxil fumarate treatment (>4 weeks and ≤4 weeks), and study period (before and after the change in therapeutic algorithm) and was measured in a modified intention-to-treat analysis, which excluded infants lost to follow-up or who were withdrawn before 6 months. The study is registered with ClinicalTrials.gov, NCT02937779.

FINDINGS

From Oct 4, 2017, to Nov 27, 2020, 21 251 pregnant women were screened for HBsAg, of whom 1194 (6%) were enrolled in the study: 338 (28%) were eligible to receive tenofovir disoproxil fumarate. For the tenofovir disoproxil fumarate eligible group, four (1% [95% CI 0·34-3·20]) of 317 infants had HBV infection at 6 months; in the subgroup of 271 children who did not receive HBIg, four (1% [0·40-3·74]) had HBV infection at 6 months. In absence of HBIg, MTCT HBV transmission occurred in none (0% [0-1·61]) of 227 women who received tenofovir disoproxil fumarate for more than 4 weeks before giving birth and three (8% [1·75-22·47]) of 36 women who received tenofovir disoproxil fumarate for less than 4 weeks. In the tenofovir disoproxil fumarate ineligible group, seven (1% [0·40-2·02]) of 712 infants had HBV infection at 6 months; in the subgroup of 567 children who did not receive HBIg, six (1% [0·39-2·30]) had HBV infection at 6 months.

INTERPRETATION

An immunoglobulin-free strategy using an HBeAg rapid diagnosis test and alanine aminotransferase-based algorithm to assess eligibility for tenofovir, is effective at preventing MTCT of HBV when tenofovir was initiated at least 4 weeks before birth.

FUNDING

French Agency for Research on AIDS and Viral Hepatitis and Emerging Infectious diseases.

TRANSLATION

For the French translation of the abstract see Supplementary Materials section.

Tenofovir disoproxil fumarate therapy to prevent hepatitis B virus vertical transmission-A review of maternal and infant outcomes

Hepatitis B virus (HBV) is a global health problem. Vertical transmission of HBV from HBV surface antigen (HBsAg)-positive mothers to their infants is the most common cause of HBV infection worldwide. The use of passive-active immunoprophylaxis is >90% effective in reducing the risk of vertical transmission, but immunoprophylaxis failure can occur in infants born to mothers with high viraemia. Thus, it is recommended that pregnant women with HBV-DNA level >200 000 IU/ml receive nucleos(t)ide analogue (NA) treatment [i.e. tenofovir disoproxil fumarate (TDF), lamivudine or telbivudine] during third trimester to prevent infant immunoprophylaxis failure. TDF is recommended as the first-line therapy based on available data on efficacy, safety and resistance profile. However, maternal immunological reconstitution following parturition can increase immune-mediated flares to viral antigens that is potentially exacerbated following TDF withdrawal. In this article, we review available data on the efficacy and safety of TDF administration to prevent HBV mother-to-child transmission. We also discuss changes in maternal viral markers [i.e. HBV-DNA, HBV e antigen and HBsAg] and alanine aminotransferase during follow-up post-partum in mothers received NA to prevent HBV vertical transmission.

Plasma and breast milk pharmacokinetics of tenofovir alafenamide in mothers with chronic hepatitis B infection

BACKGROUND

Antenatal antiviral therapy (AVT) is effective in preventing mother-to-child transmission (MTCT) in chronic hepatitis B (CHB); tenofovir disoproxil fumarate (TDF) is the preferred agent. Tenofovir alafenamide (TAF) is a prodrug of tenofovir (TFV) similar to TDF, with improved bone and renal safety. There are no data on TAF breast milk pharmacokinetics and exposure to breastfeeding infants in CHB.

AIM

To assess the pharmacokinetics of TAF/TFV in breastfeeding women with CHB on TAF monotherapy.

METHODS

Pregnant women with CHB requiring AVT commenced TAF 25 mg daily at third trimester or postpartum. Sample collection occurred while breastfeeding and taking TAF for minimum 4 weeks. Maternal blood, breast milk and infant urine samples were collected. Drug concentrations were measured by LCMS/MS analyses using validated methods. Non-compartmental analyses were performed to quantify the pharmacokinetic parameters.

RESULTS

Eight women provided samples. In breast milk and plasma, median TAF half-life was 0.81 and 0.94 h, respectively, and C_max 1.69 and 120.5 ng/ml, respectively. Median maternal breast milk to plasma (M/P) ratio of TAF was 0.029; for and TFV it was 2.809. The relative infant dose of TAF was 0.005% of maternal dose, well below safety threshold of 5-10%. TFV was detectable in three out of seven infant urine samples with median steady-state concentration of 5 ng/ml being 300-2500 times less than reported adult steady-state urine concentrations in those taking TAF and TDF, respectively.

CONCLUSIONS

In this first pharmacokinetic study of TAF monotherapy in breastfeeding women with CHB, concentrations of TAF and TFV were low in breast milk with negligible infant exposure, supporting the use of TAF to prevent MTCT.

Seroprevalence of Hepatitis B, C and D in Vietnam: A systematic review and meta-analysis

Background

Vietnam has one of the greatest disease burdens from chronic viral hepatitis. Comprehensive prevalence data are essential to support its elimination as a public health threat.

Methods

We searched Medline and Embase from 1990 to 2021 for seroprevalence data relating to Hepatitis B (HBV), C (HCV) and D (HDV) in Vietnam. We estimated pooled prevalence with a DerSimonian-Laird random-effects model and stratified study populations into i) low-risk ii) high-risk exposure and iii) liver disease. We further estimated prevalence by decade and region and rates of HIV-coinfection.

Findings

We analysed 72 studies, including 120 HBV, 114 HCV and 23 HDV study populations. Pooled HBV prevalence was low in blood donors (1.86% [1.82-1.90]) but high in antenatal populations (10.8% [10.1-11.6]) and adults in the general population (10.5% [10.0-11.0]). It was similar or modestly increased in groups at highest risk of exposure, suggesting the epidemic is largely driven by chronic infections acquired in childhood. HCV pooled prevalence in the general population was lower than historical estimates: 0.26% (0.09-0.51) have active infection defined by detectable antigen or HCV RNA. In contrast, there is an extremely high prevalence of active HCV infection in people who inject drugs (PWID) (57.8% [56.5-59.1]), which has persisted through the decades despite harm-reduction interventions. HDV appears mainly confined to high-risk groups.

Interpretation

Blood safety has improved, but renewed focus on HBV vaccination at birth and targeted HCV screening and treatment of PWID are urgently required to meet elimination targets. Large cross-sectional studies are needed to better characterize HDV prevalence, but mass screening may not be warranted.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

The role of tenofovir disoproxil fumarate for preventing vertical transmission of hepatitis B

Background

Since immunoprophylaxis failure can occur if maternal serum hepatitis B virus (HBV) DNA levels are >200,000 IU/ml, tenofovir disoproxil fumarate (TDF) therapy has been investigated for preventing mother to child transmission (PMTCT).

Methods

A literature search for maternal TDF therapy for PMTCT between 1/1/2015 and 7/1/21 on PUBMED, EMBASE, Cochrane, CNKI, and Wanfang databases was performed. Data from RCTs in English or Chinese were extracted and reviewed. The outcomes of interest included the efficacy and safety of TDF versus placebo for PMTCT.

Results

Among 11 RCTs identified from the databases, the risk-of-bias was low. All studies demonstrated that maternal TDF therapy initiated from the second or third trimester for highly viremic chronic hepatitis B mothers is highly effective and safe in the PMTCT of HBV, except one RCT performed in Thailand which showed no therapeutic advantage on TDF treatment versus placebo for PMTCT (0% vs 3% transmission). Recent emerging data suggest that maternal TDF therapy initiated at the 2nd or early 3rd trimester in mothers with HBV DNA >200,000 IU/ml achieved viremic control before delivery. In the 4-year long follow-up study for maternal TDF therapy, there were no impacts on infants’ physical growth, psychological or mental development, and bone mineral density after fetal exposure to TDF. In the light of updated efficacy and safety data from RCTs, an algorithm was proposed. The approaches in resource-limit areas were discussed.

Conclusions

TDF is safe for both mothers and infants as the preferred therapy for PMTCT in highly viremic mothers. TDF should be initiated at the second or early third trimester in the combination of the appropriate infants’ immunoprophylaxis.

Asian Pacific association for the study of liver (APASL) guidelines: hepatitis B virus in pregnancy

Hepatitis B virus (HBV) infection still remains a major public health issue in the Asia-Pacific region. Most of the burden of HBV-related disease results from infections acquired in infancy through perinatal or early childhood exposure to HBV in Asia-Pacific. Hepatitis B during pregnancy presents unique management issues for both the mother and fetus. These APASL guidelines provide a comprehensive review and recommendations based on available evidence in the literature, for the management of females with HBV infection through every stage of pregnancy and postpartum. These also address the concerns, management challenges, and required follow-up of children born to hepatitis B-positive mothers.

Long-term safety of infants from mothers with chronic hepatitis B treated with tenofovir disoproxil in China

OBJECTIVE

The physical and neuromental development of infants remains uncertain after fetal exposure to tenofovir disoproxil fumarate (TDF) for the prevention of mother-to-child transmission of HBV. We aimed to investigate the safety of TDF therapy during the third trimester of pregnancy.

DESIGN

Infants from a previous randomised controlled trial were recruited for our long-term follow-up (LTFU) study. Mothers with chronic hepatitis B were randomised to receive TDF therapy or no treatment during the third trimester. Infants' physical growth or malformation, bone mineral density (BMD) and neurodevelopment, as assessed using Bayley-III assessment, were examined at 192 weeks of age.

RESULTS

Of 180 eligible infants, 176/180 (98%) were enrolled and 145/176 (82%) completed the LTFU (control group: 75; TDF-treated group: 70). In the TDF-treated group, the mean duration of fetal exposure to TDF was 8.57±0.53 weeks. Congenital malformation rates were similar between the two groups at week 192. The mean body weight of boys in the control and TDF-treated groups was significantly higher (19.84±3.46 kg vs. 18.47±2.34 kg; p=0.03) and within the normal range (18.48±2.35 kg vs. 17.80±2.50 kg; p=0.07), respectively, when compared with the national standard. Other prespecified outcomes (head circumference, height, BMD, and cognitive, motor, social-emotional, and adaptive behaviour measurements) were all comparable between the groups.

CONCLUSION

Infants with fetal exposure to TDF had normal physical growth, BMD and neurodevelopment at week 192. Our findings provide evidence on the long-term safety of infants after fetal exposure to maternal TDF therapy for preventing hepatitis B transmission.

TRIAL REGISTRATION NUMBER

NCT01488526.

Psychological stress; knowledge, attitude and practice and acceptance of antiviral therapy in pregnant women with hepatitis B in Zhejiang, China: a case comparison study

OBJECTIVES

To determine knowledge, attitude and practice (KAP) and antiviral therapy's acceptance during pregnancy of pregnant women with hepatitis B and influencing factors.

DESIGN

Case-comparison study.

SETTING

The study was conducted in Zhejiang province, China, from September 2019 to December 2020.

PARTICIPANTS

Pregnant and postpartum women with chronic hepatitis B.

PRIMARY AND SECONDARY OUTCOME MEASURES

The stress scores, self-assessed health score, KAP, antiviral therapy's acceptance rate during pregnancy and influencing factors were analysed. The Perceived Stress Scale-10 was used to assess stress. Logistic regression was used to analyse influencing factors on antiviral therapy.

RESULTS

The self-assessed health score of pregnant women without liver diseases (82.4±9.3) was significantly higher than that of pregnant women with chronic hepatitis B (75.5±9.5) and postpartum (75.1±14.1). Psychological stress of pregnant women with chronic hepatitis B was significantly high with a 14.9±3.6 score, but there was no significant difference between hepatitis B postpartum and non-liver disease women (12.7±3.5 vs 12.9±3.5, p=0.75). The acceptance rate of pregnant women with hepatitis B for antiviral therapy was 84.2%, while that of postpartum women was even higher. Logistic regression analysis showed that patients with positive hepatitis B e antigen (HBeAg) (OR, 3.35; 95% CI, 1.21 to 9.26) and higher scores on hepatitis B-related knowledge (OR, 3.52, 95% CI, 2.18 to 5.69) were more likely to accept antiviral therapy during pregnancy.

CONCLUSIONS

Pregnant women with hepatitis B in Zhejiang have heavy psychological stress and a high antiviral therapy acceptance rate during pregnancy. Acceptance is related to HBeAg status and level of understanding of hepatitis B during pregnancy. It is necessary to provide education on hepatitis B to reduce psychological stress and increase acceptance of antiviral therapy during pregnancy.

Translational Strategies to Eliminate Chronic Hepatitis B in Children: Prophylaxis and Management in East Asian Countries

Translational medical research on hepatitis B virus (HBV) infection and chronic hepatitis B (CHB) pathogenesis provides guidance on strengthening the treatment and prevention strategies of CHB. Preventing vertical transmission is the key to eliminating HBV infection in children. The understanding of HBV replication, hepatocyte turnover, and the fate of covalently closed circular DNA (cccDNA) would help establish a personalized application of the guidelines, especially concerning the discontinuation of nucleos(t)ide analog (NA) treatment in children. Transplacental leakage of HBV-infected maternal blood is suggested as the leading cause of vertical transmission. Prenatal maternal prophylaxis could diminish maternal HBV viremia at delivery, to reduce the risk of neonatal HBV infection. The meaning of the expression "no additional risk of breast milk feeding" is thereby explained. Understanding the untreated natural course of CHB in children and the course changeable by treatment is important to apply individualistic strategies and avoid the immoral selection of treatment indications. NAs with potent efficacy and a high barrier to drug resistance should be used as first-line treatment to reduce the likelihood of NA-resistant HBV development because the rate of mutant HBV emergence might count on the infected hepatocyte turnover rate in chronic HBV infection. Although elimination of intranuclear cccDNA is difficult by NAs alone, a cure is possible by human immunity and hepatocyte turnover. The reduction of intranuclear cccDNA occurs after the destruction of HBV-infected hepatocytes, non-cytolytic immune response, apoptosis of hepatocytes, and compensatory cell proliferation. Therefore, consolidation therapy after NA-induced hepatitis B e-antigen seroconversion must be necessary for a sufficient period. This review also summarizes the treatment strategies of CHB in children based on the practical application of translational research.

Kinetics of hepatitis B surface antigen in pregnant women with and without tenofovir disoproxil fumarate

Tenofovir disoproxil fumarate (TDF) is the preferred treatment to prevent mother-to-infant transmission in highly viremic HBV-infected women. Data on hepatitis B surface antigen (HBsAg) levels in pregnant women are lacking. We aimed to investigate prepartum and postpartum HBsAg kinetics and its correlation with HBV DNA in pregnant women. HBV-infected mothers with HBV DNA ≥7.5 log₁₀  IU/ml were tested for HBsAg and HBV DNA from baseline to 6 months postpartum. Of the 186 pregnant women with comparable baseline HBsAg and HBV DNA, 101 received TDF from the third trimester until 1 month postpartum. At delivery, TDF group had mildly lower HBsAg (4.32 ± 0.47 vs. 4.54 ± 0.35 log₁₀  IU/ml, p = .0004) and markedly lower HBV DNA (4.26 ± 0.97 vs. 8.11 ± 0.70 log₁₀  IU/ml, p < .0001) than the control group. In the TDF group, mean reduction of HBsAg and HBV DNA from baseline to delivery were 0.22 ± 0.38 and 3.96 ± 0.93 log₁₀  IU/ml. HBsAg reduction had a positive correlation (r = .309; p = .0017) with HBV DNA reduction, and was predictive of HBV DNA reduction ≥3 log₁₀  IU/ml (area under the receiver operating characteristic curve, 0.67; 95% confidence interval, 0.50-0.82). At 6 months postpartum, TDF and control group had comparable HBsAg and HBV DNA. In conclusion, HBsAg decreased slightly at delivery in pregnant women receiving TDF. For monitoring the effect of antiviral therapy during pregnancy, HBV DNA is a better marker than HBsAg. Our data provided valuable information regarding monitoring HBV-infected pregnant women using antiviral therapy.

Infection courses, virological features and IFN-α responses of HBV genotypes in cell culture and animal models

BACKGROUND & AIMS

HBV consists of 9 major genotypes (A to I), 1 minor strain (designated J) and multiple subtypes, which may be associated with different clinical characteristics. As only cell lines expressing genotype D3 have been established, herein, we aimed to establish stable cell lines producing high-titer cell culture-generated HBV (HBVcc) of different genotypes and to explore their infectivity, virological features and responses to treatment.

METHODS

Stable cell lines producing high titers of HBV genotype A2, B2, C1, E, F1b and H were generated by transfecting plasmids containing a replication-competent 1.3x length HBV genome and an antibiotic marker into HepG2 cells that can support HBV replication. Clones with the highest levels of HBV DNA and/or HBeAg were selected and expanded for large-scale purification of HBVcc. HBVcc of different genotypes were tested in cells and a humanized chimeric mouse model.

RESULTS

HBVcc genotypes were infectious in mouse-passaged primary human hepatocytes (PXB cells) and responded differently to human interferon (IFN)-α with variable kinetics of reduction in HBV DNA, HBeAg and HBsAg. HBVcc of all genotypes were infectious in humanized chimeric mice but with variable kinetics of viremia and viral antigen production. Treatment of infected mice with human IFN-α resulted in modest and variable reductions of viremia and viral antigenemia. HBVcc passaged in humanized chimeric mice (HBVmp) infected PXB cells much more efficiently than that of the original HBVcc viral stock.

CONCLUSIONS

Herein, we generated stable cell lines producing HBV of various genotypes that are infectious in vitro and in vivo. We observe genotype-associated variations in viral antigen production, infection kinetics and responses to human IFN-α treatment in these models.

LAY SUMMARY

Stable cell lines producing high-titer cell culture-generated hepatitis B virus (HBV) of various genotypes were established. HBV genotypes showed stable infectivity in both in vitro and in vivo models, which are valuable tools for antiviral development.

Outcomes of Hepatitis B Immunoglobulin and Hepatitis B Vaccination in High-Risk Newborns Born to HBeAg-positive Mothers

BACKGROUND

To evaluate the protective efficacy of a hepatitis B (HB) vaccination program in Taiwan among high-risk children.

MATERIAL AND METHODS

Children born to HBeAg-positive mothers from 2001 to 2010 were invited back. Blood samples for hepatitis B virus (HBV) seromarkers were taken and the children underwent hepatobiliary ultrasonography. Perinatal factors including delivery mode and vaccination history were collected from their medical records. According to the results of HBV serological markers, the children were initially classified into five groups: HBV naïve, HB vaccine responder, HBsAg carrier, recovered from HBV infection, and anti-HBc-positive alone. Children in the HBV naïve and anti-HBc-positive alone groups who presented with an anamnestic response after a booster HB vaccine were re-assigned to the vaccine responder and recovered from infection groups, respectively.

RESULTS

All of the 196 enrolled children received postnatal hepatitis B immunoglobulin (HBIG) and HB vaccinations, of whom one was HBV naïve (0.5%), 109 were vaccine responders (55.6%), 21 were carriers (10.7%), and 65 recovered from infection (33.2%). Among the 21 carriers, 14 (66.7%) presented in the immunotolerant phase. Cesarean section was the only significant perinatal factor between the carriers (5.3%) and those who recovered from infection (37.7%) (p=0.007).

CONCLUSIONS

In this study, there was a 43.9% HBV infection rate and 10.7% HBsAg carrier rate in high-risk Taiwanese children even after receiving HBIG and HB vaccinations. Cesarean section may protect newborns from becoming HBsAg carriers, while HBV genotype and time of HBIG injection did not contribute to the HBV carrier rate.

Effects of intrauterine exposure to hepatitis B virus in foetuses

Foetal response to hepatitis B viral infection is still unknown. The mechanisms of persistent infection that occurs more often in mother-to-child transmission than adult transmission are also unclear. Various aspects of the environmental factors that accelerate or inhibit infection and the cytokine responses are associated with the persistence of infection. Several studies showed that the cytokine poor immune response in immaturity causes the persistence of the infection. However, some reports suggested that a mature immune response was the cause of this persistent infection. This review comprehensively summarized the reports from in vitro, in vivo as well as clinical reports regarding the responses of the foetuses of hepatitis B infected mothers to the micro-organism. The mechanism of more opportunities to be persistently infected via the mother-to-child transmission route is also summarized and discussed. Since there are limited clinical reports at this time, this review will provide evidence for future studies regarding the intrauterine infection mechanism and foetal response to hepatitis B virus to elucidate the mechanisms responsible for mother-to-child transmission. This understanding may lead to effective interventions to control mother-to-child hepatitis B infection in the future.

Clinical and Immunological Factors Associated with Postpartum Hepatic Flares in Immune-Tolerant Pregnant Women with Hepatitis B Virus Infection Treated with Telbivudine

BACKGROUND/AIMS

To investigate postpartum hepatic flares and associated factors in highly viremic pregnant patients in the immune tolerance phase who adopted telbivudine (LdT) treatment in the last trimester to reduce vertical transmission of hepatitis B virus.

METHODS

Hepatitis B e antigen (HBeAg)-positive, highly viremic pregnant women were recruited for this prospective study. Treatment with LdT was started from 28 weeks of gestation. Virological and biochemical markers were examined before LdT treatment, antepartum and postpartum. Serial blood samples at the same time were collected to detect cytokines and cortisol (COR).

RESULTS

Fifty-six of 153 patients (36.6%) had postpartum hepatic flares, defined as a 2-fold increase in alanine aminotransferase 6 weeks after delivery. Age and the antepartum alanine aminotransferase and postpartum HBeAg levels were independent influencing factors of postpartum hepatic flares. Cytokines showed no regularity during or after pregnancy. Compared with the patients with no postpartum flares, the patients with flares had lower baseline interferon γ and COR levels (p=0.022 and p=0.028) and higher postpartum interferon γ levels (p=0.026).

CONCLUSIONS

A high proportion of highly viremic and immune-tolerant pregnant patients treated with LdT in the last trimester had postpartum hepatic flares, which implied that these patients entered the immune clearance phase after delivery. Thus, this may create an appropriate opportunity for re-antiviral therapy.

Use of Hepatitis B-e Antigen to Identify Pregnant Women With Hepatitis B Virus Infection Who Need Antiviral Therapy for Prevention of Mother-to-child Transmission

Objective To evaluate the performance of hepatitis B-e antigen (HBeAg) for identifying pregnant women infected with hepatitis B virus (HBV) who are having a high viral load. Methods A cross-sectional study was conducted at the tertiary care hospital in Bangkok, Thailand between August 2017 and August 2018. Ninety-six pregnant women having positive hepatitis B-s antigen (HBsAg) results were invited to participate into the study. Clinical data and blood samples were collected and tested for HBeAg and HBV DNA levels. Data were reported as percentage and 95% confidence interval (CI). Results High viral load was found in 25 women (26.0%, 95% CI: 18.3% to 35.6%) and HBeAg showed positive results in 33 women (34.4%, 95% CI: 25.6% to 44.3%). Among antiviral-naïve women, 24 of 30 cases having positive HBeAg results had high viral load (80.0%, 95% CI: 62.7% to 90.5%) while only 1 of 62 negative HBeAg women had high viral load (1.6%, 95% CI: 0.3% to 8.6%). Conclusion About one-fourth of HBV-infected pregnant women were at high risk for mother-to-child transmission (MTCT) of the virus and needed antiviral drugs for reducing MTCT. HBeAg may be used to identify women at high risk for MTCT of HBV in a low-resource setting where HBV DNA level test is not available.

Comparison of the efficacy and safety of tenofovir and telbivudine in interrupting mother-to-child transmission of hepatitis B virus

The present study is aimed to evaluate and compare the efficacy and safety of tenofovir (TDF) and telbivudine (TBV) in interrupting hepatitis B virus (HBV) mother-to-child transmission (MTCT), and to provide evidence-based treatment options to clinicians and patients.Hepatitis B e-antigen (HBeAg)-positive pregnant women (644 in total) with high HBV DNA load (≥2 × 105 IU/mL) and who received TDF (n = 214) or TBV (n = 380) in the second or third trimester, or received no treatment (n = 50) were included in this retrospective analysis.HBV DNA levels in mothers at delivery were significantly lower than baseline in the 2 treatment groups. HBV DNA levels in the TDF group were significantly different between the mothers receiving treatment in the second trimester and those receiving treatment in the third trimester; however, significant difference was not observed in the TBV group. The proportion of hepatitis B surface antigen (HBsAg)-positive infants at the age of 7 to 12 months in the TDF, TBV, and control groups were 0.00% (0/174), 0.30% (1/331), and 5.0% (2/40) with a significant difference between the treatment groups and the control group, but no difference between the TDF and TBV group (P > .05). However, no serious adverse events were observed in infants and mothers of all groups.TBV and TDF can effectively reduce the HBV DNA level and MTCT rate in pregnant women with high HBV DNA load (≥2 × 105 IU/mL); both antiviral drugs are safe for infants and mothers. Since TDF was more effective in reducing HBV DNA levels during the second trimester, its use during the period is recommended to prevent HBV MTCT.

Arresting vertical transmission of hepatitis B virus (AVERT-HBV) in pregnant women and their neonates in the Democratic Republic of the Congo: a feasibility study

BACKGROUND

Hepatitis B virus (HBV) remains endemic throughout sub-Saharan Africa despite the widespread availability of effective childhood vaccines. In the Democratic Republic of the Congo, HBV treatment and birth-dose vaccination programmes are not established. We, therefore, aimed to evaluate the feasibility and acceptability of adding HBV testing and treatment of pregnant women as well as the birth-dose vaccination of HBV-exposed infants to the HIV prevention of mother-to-child transmission programme infrastructure in the Democratic Republic of the Congo.

METHODS

We did a feasibility study in two maternity centres in Kinshasa: Binza and Kingasani. Using the already established HIV prevention of mother-to-child transmission programme at these two maternity centres, we screened pregnant women for HBV infection at routine prenatal care registration. Those who tested positive and had a gestational age of 24 weeks or less were included in this study. Eligible pregnant women with a high viral load (≥200 000 IU/mL or HBeAg positivity, or both) were considered as having HBV of high risk of mother-to-child transmission and initiated on oral tenofovir disoproxil fumarate (300 mg/day) between 28 weeks and 32 weeks of gestation and continued through 12 weeks post partum. All HBV-exposed infants received a birth-dose of monovalent HBV vaccine (Euvax-B Pediatric: Sanofi Pasteur, Seoul, South Korea; 0·5 mL) within 24 h of life. All women were followed up for 24 weeks post partum, when they completed an exit questionnaire that assessed the acceptability of study procedures. The primary outcomes were the feasibility of screening pregnant women to identify those at high risk for HBV mother-to-child transmission and to provide them with antiviral prophylaxis, the feasibility of administrating the birth-dose vaccine to exposed infants, and the acceptability of this prevention programme. This study is registered with ClinicalTrials.gov, NCT03567382.

FINDINGS

Between Sept 24, 2018, and Feb 22, 2019, 4016 women were approached and screened. Of these pregnant women, 109 (2·7%) were positive for HBsAg. Of the 109 women, 91 (83%) met the eligibility criteria for participation. However, only data from 90 women-excluding one woman who had a false pregnancy-were included in the study analysis. The median overall age of the enrolled women was 31 years (IQR 25-34) and the median overall gestational age was 19 weeks (15-22). Ten (11%) of 91 women evaluated had high-risk HBV infection. Nine (90%) of the ten pregnant women with high-risk HBV infection received tenofovir disoproxil fumarate and one (10%) refused therapy and withdrew from the study; five (56%) of the nine women achieved viral suppression (ie, <200 000 IU/mL) on tenofovir disoproxil fumarate therapy by the time of delivery and the remaining four (44%) had decreased viral loads from enrolment to delivery. A total of 88 infants were born to the 90 enrolled women. Of the 88 infants, 60 (68%) received a birth-dose vaccine; of these, 46 (77%) received a timely birth-dose vaccine. No cases of HBV mother-to-child transmission were observed. No serious adverse events associated with tenofovir disoproxil fumarate nor with the birth-dose vaccine were reported. Only one (11%) of nine women reported dizziness during the course of tenofovir disoproxil fumarate therapy. The study procedures were considered highly acceptable (>80%) among mothers.

INTERPRETATION

Adding HBV screening and treatment of pregnant women and infant birth-dose vaccination to existing HIV prevention of mother-to-child transmission platforms is feasible in countries such as the Democratic Republic of the Congo. Birth-dose vaccination against HBV infection integrated within the current Expanded Programme on Immunisation and HIV prevention of mother-to-child transmission programme could accelerate progress toward HBV elimination in Africa.

FUNDING

Gillings Innovation Laboratory award and the National Institutes of Health.

TRANSLATIONS

For the French and Lingala translations of the abstract see Supplementary Materials section.

Guidelines for Prevention and Treatment of Chronic Hepatitis B

To achieve the goal of the World Health Organization to eliminate viral hepatitis as a major public health threat by 2030, the Chinese Society of Infectious Diseases and the Chinese Society of Hepatology convened an expert panel in 2019 to update the guidelines for the prevention and treatment of chronic hepatitis B (CHB). The current guidelines cover recent advances in basic, clinical, and preventive studies of CHB infection and consider the actual situation in China. These guidelines are intended to provide support for the prevention, diagnosis, and treatment of CHB.

Vertical transmission of hepatitis B virus: propositions and future directions

ABSTRACT

Chronic hepatitis B virus (HBV) infection due to vertical transmission remains a critical concern with regards to eliminating HBV infection. Implementation of hepatitis B vaccine, the foundation to prevent perinatal and horizontal transmission, has reduced the prevalence of HBV by >80%. In countries where the hepatitis B immune globulin (HBIG) is available, such as China and the United States, the administration of HBIG and hepatitis B vaccine to the infants of mothers who are positive for hepatitis B surface antigen has become a standard practice and is effective in preventing vertical transmission. Accumulating evidence on the efficacy and safety of antiviral prophylaxis during pregnancy indicates the probability of attaining the goal of the World Health Organization to eliminate hepatitis by 2030. In this review, we discuss the transmission routes, diagnostic criteria, and preventive strategies for vertical transmission. A preventive program that includes screening before pregnancy, antiviral prophylaxis during pregnancy, and postpartum immunoprophylaxis provides "perfect strategies" to eliminate vertical transmission. However, there is still a notable gap between "perfect strategies" and real-world application, including insufficient coverage of timely birth dose vaccine and the efficacy and necessity of HBIG, especially in mothers who are negative for hepatitis B envelope antigen. In particular, there is a clear need for a comprehensive long-term safety profile of antiviral prophylaxis. Therefore, feasible and cost-effective preventive strategies need to be determined across regions. Access also needs to be scaled up to meet the demands for prophylaxis and prevalence targets.

Application of hepatitis B immunoglobulin in prevention of mother-to-child transmission of chronic hepatitis B in HBsAg- and HBeAg-positive mother

The aim of our study was to compare the efficacy of two dosages of hepatitis B immunoglobulin (HBIG) combined with HBV vaccine (HBVac) to prevent mother-to-child transmission (MTCT) of hepatitis B in HBsAg- and HBeAg-positive mother. We enrolled 331 mother-infant pairs with HBsAg- and HBeAg-positive maternal state from the Women's Hospital School of Medicine of Zhejiang University. Newborns were randomly distributed into two groups according to the dosages of HBIG injection: 100 IU and 200 IU. Newborns from both groups were injected with HBVac in the same doses. We compared the immune outcomes between the two groups and explore the influencing factors of immune outcomes through regression analysis. There was no statistically significant relationship between HBsAg serological transmission of newborns and dosages of HBIG in HBsAg- and HBeAg-positive mother (p > .05). The Logistic regression showed that high DNA load is a risk factor for passive-active immunoprophylaxis failure for both 100 IU and 200 IU group, but higher-dosage HBIG is not necessary for higher-viral-load pregnant women with HBsAg- and HBeAg-positive. In conclusion, combined application of HBVac and a single dose of 100 IU HBIG can achieve the ideal MTCT interruption results for HBsAg- and HBeAg-positive pregnant women.IMPACT STATEMENTWhat is already known on this subject? Passive-active immunoprophylaxis is proved to be effective in preventing mother-to-child transmission of hepatitis B. Hepatitis B vaccine combined with 100 IU or 200 IU immunoglobulin is mostly recommended in China.What do the results of this study add? At present, there is still a lack scientific basis for improving existing strategies and measures to prevent mother-to-child transmission of hepatitis B in China.What are the implications of these findings for clinical practice and/or further research? 100 IU and 200 IU immunoglobulin show equivalent blocking effect, and combined use of hepatitis B vaccine and 100 IU immunoglobulin is more cost-effective.

Characterization of T cell immunity in chronic hepatitis B virus-infected mothers with postpartum alanine transaminase flare

BACKGROUND

Postpartum alanine transaminase (ALT) flares occur frequently in chronic hepatitis B virus (HBV)-infected mothers with antepartum antiviral therapy (AVT). We aimed to characterize the T cell immunity in HBV-infected mothers experiencing postpartum ALT flares.

METHODS

Twenty HBV-infected pregnant women who received AVT at 26-28 weeks of gestation were enrolled and followed up until 15-18 weeks postpartum. Among the 20 HBV-infected pregnant women, 6 experienced postpartum ALT flare (AF mothers), while 14 did not (NAF mothers). T lymphocyte phenotypes and functions were analyzed using flow cytometry.

RESULTS

Compared to NAF mothers, the quantitative HBsAg levels in AF mothers decreased significantly at 6-8 or 15-18 weeks postpartum. Significant differences in HBeAg levels between these groups were only found at delivery. Regulatory T cell (Treg) numbers in AF mothers were lower than those of NAF mothers before AVT; however, there were no significant differences in Treg numbers at other follow-up points. Expression of other T cell phenotypes were similar between the two groups. T cells in AF mothers produced more pro-inflammatory cytokines (IFN-γ, IL-21, TNF-α, IL-2) or less anti-inflammatory cytokine (IL-10) than those in NAF mothers before, during, or after antiviral treatment. The ratio of IFN-γ to IL-10 producing by CD4⁺ T cells or CD8⁺ T cells was higher in AF mothers than that in NAF mothers during pregnancy or after delivery.

CONCLUSIONS

The characteristics of T cell immunity was distinct between mothers with postpartum ALT flare and those without ALT flare from pregnancy to postpartum, which indicated that T cell immunity might get involved in postpartum ALT flare.

The effects of increased dose of hepatitis B vaccine on mother-to-child transmission and immune response for infants born to mothers with chronic hepatitis B infection: a prospective, multicenter, large-sample cohort study

BACKGROUND

Appropriate passive-active immunoprophylaxis effectively reduces mother-to-child transmission (MTCT) of hepatitis B virus (HBV), but the immunoprophylaxis failure was still more than 5% under the current strategy. The study objective was to investigate the effects of high dose of HB vaccine on MTCT and immune response for infants born to hepatitis B surface antigen (HBsAg)-positive mothers.

METHODS

This was a prospective, multicenter, large-sample cohort study in four sites of China, and 955 pairs of HBsAg-positive mothers and their infants were enrolled in our investigation. The infants were given 10 μg or 20 μg HB vaccine (at age 0, 1, and 6 months) plus HB immunoglobulin (at age 0 and 1 month). Serum HBsAg, antibody to HBsAg (anti-HBs), and/or HBV DNA levels in the infants were determined at age 12 months. The safety of 20 μg HB vaccine was evaluated by adverse events and observing the growth indexes of infants.

RESULTS

Thirteen of 955 infants were HBsAg-positive at 12 months. Stratification analysis showed that immunoprophylaxis failure rates in the 20 μg group were not significantly different from the 10 μg group, whatever maternal HBV load was high or not. But the high dose of HB vaccine significantly reduced low-response rate (anti-HBs 10-100 IU/L) (P = 0.002) and middle-response rate (anti-HBs 100-1000 IU/L) (P = 0.022) and improved high-response rate (anti-HBs ≥ 1000 IU/L) (P < 0.0001) in infants born to mothers with HBV DNA < 5 log10 IU/mL. For infants born to mothers with HBV DNA ≥ 5 log10 IU/mL, 20 μg HB vaccine did not present these above response advantages. The 20 μg HB vaccine showed good safety for infants.

CONCLUSIONS

The 20 μg HB vaccine did not further reduce immunoprophylaxis failure of infants from HBsAg-positive mothers, but increased the high-response and decreased low-response rates for infants born to mothers with HBV DNA < 5 log10 IU/mL.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-PRC-09000459.