Efficacy and safety of antiviral therapy for HBV in different trimesters of pregnancy: systematic review and network meta-analysis

Chinese clinical practice guidelines for the prevention and treatment of mother-to-child transmission of hepatitis B virus (version 2024)

Guideline registration:

International Practice Guidelines Registry Platform (PREPARE-2023CN171).

Accelerating the momentum to achieve global elimination of hepatitis B infection: a scoping review of hepatitis B guidelines to reduce mother to child transmission

Progress towards achieving global elimination of hepatitis B virus (HBV) by 2030 remains unsatisfactory. Prevention of mother to child transmission is crucial but current Clinical Practice Guidelines (CPGs) gave diverse recommendations, creating confusion and leading to significant challenges in the practical implementation across various regions owing to global inequity. We reviewed 47 CPGs on the management of hepatitis B during pregnancy against twelve important clinical questions. Of 47 guidelines, 80.9% (38/47) supported the universal approach to HBV screening. To select women for antiviral prophylaxis, 78.7% (37/47) recommended the use of HBV DNA levels, while 31.9% (15/47) recommended the use of HBeAg. Of 37 guidelines recommending HBV DNA levels, 94.6% (35/37) recommended a viral load threshold of >200,000 IU/mL to initiate antiviral prophylaxis. Of 16 guidelines addressing the mode of delivery, 87.5% (14/16) encouraged vaginal birth. Of 30 guidelines addressing breastfeeding, 60% (18/30) recommended breastfeeding. However, controversies were found in the optimal timing of HBV disease evaluation during pregnancy and the ideal timing to stop antiviral prophylaxis after delivery. Of 36 guidelines addressing the timing to initiate antiviral prophylaxis, 25% (9/36) advised starting prophylaxis between 24 and 28 weeks, while 75% (27/36) suggested other timings or provided vague descriptions. Of 38 guidelines addressing birth-dose vaccination, 42% (16/38) emphasized the importance of "vaccination as soon as possible after birth." These deficiencies and discrepancies among CPGs could significantly impede global HBV elimination.

Effect of invasive tests during pregnancy on perinatal transmission of hepatitis B infection: a scoping review

Prenatal and intrapartum invasive tests are possible mechanisms of mother to child transmission (MTCT) of hepatitis B virus (HBV). The viral activity can affect the MTCT risk after invasive tests, but the evidence is scarce. This scoping review discussed the effects of prenatal or intrapartum invasive tests on the risk of HBV MTCT. The risk of MTCT after amniocentesis was low among hepatitis B infected pregnant individuals with negative hepatitis B e antigen (HBeAg) statuses or HBV DNA < 7 log10 IU/mL, and comparable to those that did not undergo prenatal invasive tests. Amniocentesis could increase the risk of MTCT among women with seropositive HBeAg statuses or HBV DNA ≥ 7 log10 IU/mL, but there were no MTCT among these women who received antiviral treatment. Data on CVS, cordocentesis and intrapartum invasive tests were insufficient to conclude their effects on MTCT. We also reviewed 50 international clinical practice guidelines. Most of them did not have recommendations on the management of hepatitis B infected pregnant individuals requiring prenatal or intrapartum invasive tests and significant discrepancies existed among the remaining guidelines. A workflow and two pragmatic approaches were discussed to assist clinical management. Furthermore, we would like to encourage future research to provide comprehensive data on the factors influencing the MTCT rate (such as maternal HBV DNA viral load and HBeAg status, availability and timing of neonatal birth dose immunizations, transplacental or transamniotic invasive tests, complications of the invasive tests and the use of antiviral prophylaxis).

Economic evaluation of tenofovir disoproxil fumarate prophylaxis to prevent mother-to-child transmission of Hepatitis B virus infection: evidence from a lower-middle income country

No cost-effectiveness information of preventive strategies for mother-to-child transmission (MTCT) of hepatitis B virus (HBV) has existed for policy decision making. This study aimed to compare the cost-effectiveness of alternative strategies to prevent MTCT of HBV in Vietnam. Cost-utility analysis using a hybrid decision-tree and Markov model were performed from healthcare system and societal perspectives. Preventive strategies included HBV universal vaccination (S1), hepatitis B immunoglobulin (HBIG) for infants of mothers with HBeAg( +) (S2), HBIG for infants of mothers with HBsAg( +) (S3), tenofovir disoproxil fumarate (TDF) for mothers with high viral load (S4) and mothers with HBeAg( +) (S5), and the current practice (S6) with HBV vaccine in all infants and TDF for high viral load mothers. The current practice was dominant to all preventive strategies with interventions in only infants for both perspectives. In contrast, the strategies S4 and S5 were dominant to the current practice with incremental net monetary benefit varying from $33.94 to $70.64 under a healthcare system perspective and from $44.22 to $93.71 under a societal perspective. Addition of HBIG in infants born to mothers infected HBV and tenofovir prophylaxis for mothers with positive HBeAg was the most cost-effective strategy to prevent vertical transmission of HBV in Vietnam.

Exploring the impact of hepatitis B immunoglobulin and antiviral interventions to reduce vertical transmission of hepatitis B virus

Hepatitis B virus (HBV) infection is a major public health burden. In HBV endemic regions, high prevalence is also correlated with the infections acquired in infancy through perinatal transmission or early childhood exposure to HBV, the so-called mother-to-child transmission (MTCT). Children who are infected with HBV at a young age are at higher risk of developing chronic HBV infection than those infected as adults, which may lead to worse clinical outcome. To reduce the incidence of HBV MTCT, several interventions for the infants or the mothers, or both, are already carried out. This review explores the newest information and approaches available in literature regarding HBV MTCT prevalence and its challenges, especially in high HBV endemic countries. This covers HBV screening in pregnant women, prenatal intervention, infant immunoprophylaxis, and post-vaccination serological testing for children.

Chinese Clinical Practice Guidelines for the Prevention and Treatment of Mother-to-child Transmission of Hepatitis B Virus (Version 2024)

The Chinese Clinical Practice Guidelines for the Prevention and Treatment of Mother-to-child Transmission of Hepatitis B Virus, developed by the Chinese Society of Infectious Diseases of the Chinese Medical Association in 2019, serves as a valuable reference for standardizing the prevention of mother-to-child transmission in China. As new evidence continues to emerge, it is essential to update these guidelines regularly to optimize clinical practice and research. To this end, the Infectious Disease Physician Branch of the Chinese Medical Doctor Association and the Chinese Society of Infectious Diseases of the Chinese Medical Association, in collaboration with multidisciplinary experts, have updated the guidelines based on the latest domestic and international research advancements and clinical practices, providing up-to-date guidance for clinicians and maternal and child healthcare workers.

Investigation of Mother-to-Child Transmission of Hepatitis B in Yinchuan, China: Cross-Sectional Survey Study

BACKGROUND

Hepatitis B poses a significant global public health challenge, with mother-to-child transmission (MTCT) being the primary method of hepatitis B virus (HBV) transmission. The prevalence of HBV infection in China is the highest in Asia, and it carries the greatest burden globally.

OBJECTIVE

This study aims to critically evaluate the existing local strategies for preventing MTCT and the proposed potential enhancements by analyzing the prevalence of hepatitis B among pregnant women and their neonates in Yinchuan.

METHODS

From January 2017 to December 2021, 37,557 prenatal screening records were collected. Among them, 947 pregnant women who tested positive for hepatitis B surface antigen (HBsAg) near delivery and their 960 neonates were included in an HBV-exposed group, while 29 pregnant women who tested negative and their 30 neonates were included in an HBV-nonexposed group. HBV markers in maternal peripheral blood and neonatal cord blood were analyzed using the least absolute shrinkage and selection operator (LASSO) regression, logistic regression, chi-square test, t-test, and U-test. Additionally, to further evaluate the diagnostic value of HBsAg positivity in cord blood, we conducted an additional follow-up study on 103 infants who tested positive for HBsAg in their cord blood.

RESULTS

The prevalence of HBV among pregnant women was 2.5% (947/37,557), with a declining trend every year (χ²4=19.7; P=.001). From 2018 to 2020, only 33.0% (35/106) of eligible pregnant women received antiviral medication treatment. Using LASSO regression to screen risk factors correlated with HBsAg positivity in cord blood (when log [λ] reached a minimum value of -5.02), 5 variables with nonzero coefficients were selected, including maternal hepatitis B e-antigen (HBeAg) status, maternal hepatitis B core antibody (HBcAb) status, maternal HBV DNA load, delivery method, and neonatal birth weight. Through univariate and multivariate logistic regression, delivery by cesarean section (adjusted odds ratio [aOR] 0.52, 95% CI 0.31-0.87), maternal HBeAg positivity (aOR 2.05, 95% CI 1.27-3.33), low maternal viral load (aOR 2.69, 95% CI 1.33-5.46), and high maternal viral load (aOR 2.69, 95% CI 1.32-5.51) were found to be strongly associated with cord blood HBsAg positivity. In the additional follow-up study, 61 infants successfully completed the follow-up, and only 2 were found to be infected with HBV. The mothers of both these infants had detectable HBV DNA levels and should have received standard antiviral therapy. The results of the hepatitis B surface antibody (HBsAb) positivity rate and titer test indicated a gradual decline in the immunity of vaccinated infants as the interval after vaccination increased.

CONCLUSIONS

The clinical relevance of HBV marker detection in cord blood is restricted within the current prevention measures for MTCT. There is an emphasis on the significance of public education regarding hepatitis B and the reinforcement of postnatal follow-up for the prevention of MTCT.

Chinese Clinical Practice Guidelines for the Prevention and Treatment of Mother-to-Child Transmission of Hepatitis B Virus (Version 2024)

The Chinese Clinical Practice Guidelines for the prevention and treatment of mother-to-child transmission of hepatitis B virus, developed by the Chinese Society of Infectious Diseases of the Chinese Medical Association in 2019, serves as a valuable reference for standardizing the process of preventing mother-to-child transmission in China. As new evidence emerges, it is crucial that timely and regular updates are made to the clinical practice guidelines so as to optimize guidance for clinical practice and research. To this end, the Infectious Disease Physician Branch of Chinese Medical Doctor Association and the Chinese Society of Infectious Diseases of Chinese Medical Association, in collaboration with multidisciplinary experts, have updated the guidelines based on the latest domestic and international research advancements and clinical practice, in order to provide guidance and reference for clinicians and maternal and child healthcare workers.

Unmet needs in the clinical management of chronic hepatitis B infection

The hepatitis B virus (HBV) remains a global problem despite effective tools to prevent, diagnosis, and control it. Unmet needs are identifiable across its clinical care cascade, underlining the challenges providers face in delivering effective care for patients with chronic hepatitis B. The review herein will focus on three timely clinical issues in HBV. This includes efforts to optimize delivery of perinatal HBV care, improve HBV-related hepatocellular carcinoma risk stratification models, and clarify the role of finite therapy in the HBV treatment algorithm. Important developments within these three topics will be addressed with the goal to motivate further investigation and optimization of these treatment strategies for HBV.

Comparison of the efficacy and safety of TAF, TDF, and LdT to prevent the transmission of hepatitis B in pregnant women: A retrospective study

OBJECTIVE

To compare the efficacy and safety of telbivudine (LdT), tenofovir alafenamide fumarate (TAF), and tenofovir disoproxil fumarate (TDF) for preventing hepatitis B transmission in immune-tolerant pregnant women with HBV infection.

METHODS

We conducted a retrospective cohort study involving women who had hepatitis B virus deoxyribonucleic acid (HBV DNA) ≥ 2 × 105  IU/mL and initiated LdT, TDF, or TAF to prevent mother-to-child transmission (MTCT). The primary endpoint was the safety of mothers and infants. The secondary endpoints were maternal HBV DNA reduction at delivery and MTCT rate.

RESULTS

A total of 96 patients were enrolled in the study (LdT group, n = 36; TDF group, n = 35; TAF group, n = 25). All infants received hepatitis B virus immunoprophylaxis. The MTCT rate was 0%([0 of 25] vs. [0 of 35] vs. [0 of 36], p > .05). No severe liver function damage occurred in any of the mothers. Babies delivered in all groups had prenatal ultrasound screening abnormalities, but abnormality rates were not statistically significant between groups.

CONCLUSION

The application of TDF, TAF, or LdT to immune-tolerant HBV-infected pregnant women in middle-late pregnancy can successfully interrupt MTCT of the HBV virus. However, for all three groups of pregnant women who delivered babies with abnormal prenatal ultrasound screening, an expanded sample size may be needed for further observation.

Is It Time for Treatment as Prevention of Chronic Hepatitis B?

Hepatitis B is a major global health problem with high morbidity and mortality. Approximately 296 million people are living with chronic HBV, and 1.5 million new infections are detected each year, even though a highly effective vaccine has been available for decades and viral replication and transmission can be contained with the use of drugs. Nucleoside therapy, while not curative in most cases, can control viral replication, improve prognosis, and prevent mother-to-child transmission safely. Current treatment guidelines do not include a significant number of chronically infected patients or pregnant women and are often complex to implement. Since these populations continue to have a detectable HVB viral load, they could perpetuate transmission. Expanding and facilitating treatment indications, including treatment as a public health intervention, could help control the spread of the HBV pandemic, thus bringing us closer to the goal of the United Nations General Assembly for the year 2030.

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.

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.

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.

Comparative efficacy and safety of pharmacologic interventions to prevent mother-to-child transmission of hepatitis B virus: a systematic review and network meta-analysis

OBJECTIVE

This study investigated the efficacy and safety of pharmacologic interventions to prevent vertical transmission of the hepatitis B virus.

DATA SOURCES

Medline, Cochrane, and Scopus databases were searched up to October 28, 2020.

STUDY ELIGIBILITY CRITERIA

All randomized controlled trials reporting vertical hepatitis B virus transmission with pharmacologic intervention were included.

METHODS

Risk of bias was assessed using the Cochrane Risk-of-Bias tool, version 2. Treatment efficacy was estimated using stratified network meta-analysis on the basis of maternal hepatitis B envelope antigen status.

RESULTS

Nineteen studies were included for mothers positive for hepatitis B surface and envelope antigens. Pooling indicated that a combination of hepatitis B vaccination and hepatitis B immunoglobulin in infants significantly reduced transmission risk compared with vaccination alone, with a risk ratio of 0.52 (95% confidence interval; 0.30-0.91). Only the addition of maternal tenofovir disoproxil fumarate, but not telbivudine, lamivudine, or maternal hepatitis B immunoglobulin further reduced transmission risk compared with a combination of hepatitis B vaccination and hepatitis B immunoglobulin in infants, with a pooled risk ratio of 0.10 (0.03-0.35). Twelve studies conducted in mothers with hepatitis B surface antigen positivity and mixed, unknown, or negative hepatitis B envelope antigen status provided limited evidence to suggest that maternal hepatitis B immunoglobulin combined with hepatitis B vaccination and immunoglobulin in infants was the likely best treatment, but this failed to reach statistical significance compared with a combination of hepatitis B vaccination and immunoglobulin in infants. Similarly, infant hepatitis B immunoglobulin, added to vaccination, likely provides additional benefit but failed to reach statistical significance.

CONCLUSION

A combination of hepatitis B vaccination and immunoglobulin in infants is the cornerstone for prevention of vertical transmission for mothers positive for both hepatitis B surface and envelope antigens. The addition of maternal tenofovir to this infant combination regimen was considered the likely most effective treatment. For infants of mothers with hepatitis B surface antigen positivity and mixed, unknown, or negative hepatitis B envelop antigen status, no additional agents provided further benefit beyond hepatitis B vaccination alone.

Adverse Events During Pregnancy Associated With Entecavir and Adefovir: New Insights From a Real-World Analysis of Cases Reported to FDA Adverse Event Reporting System

Background: Due to the embryotoxicity found in animal studies and scarce clinical data in pregnant women, it is still controversial whether entecavir (ETV) and adefovir dipivoxil (ADV) are safe during human pregnancy. This is of paramount importance when counseling pregnant women with hepatitis B virus (HBV) on risks and benefits to their offspring.

Objective: To quantify the association between administration of ETV and ADV in pregnant women and occurrence of adverse events (AEs) during pregnancy (AEDP).

Methods: Pregnancy reports from the FDA Adverse Event Reporting System (FAERS) were used to perform a retrospective analysis of AEDP associated with ETV or ADV. Disproportionality analysis estimating the reporting odds ratio (ROR) was conducted to identify the risk signals. A signal was defined as ROR value >2, and lower limit of 95% confidence interval (CI)> 1.

Results: A total of 1,286,367 reports involving AEDP were submitted to FAERS by healthcare professionals. Of these, there were 547 cases reporting ETV and 242 cases reporting ADV as primary suspected drugs. We found a moderate or strong signal for increased risk of spontaneous abortion when comparing ETV with tenofovir disoproxil fumarate (TDF) and telbivudine (LdT), with RORs equal to 1.58 (95% CI, 1.09–2.30) and 2.13 (95% CI, 1.04–4.36), respectively. However, when the included reports were limited to indication containing HBV infection, no signals for increased AEDP were detected. Futhermore, a strong signal for increased risk of spontaneous abortion was identified in patients with HBV infection when comparing ETV or ADV with lamivudine (LAM), with RORs of 3.55 (95% CI, 1.54–8.18) and 2.85 (95% CI, 1.15–7.08), respectively.

Conclusion: We found a strong signal for increased risk of spontaneous abortion in patients with HBV infection taking ETV or ADV, in comparison with those prescribed with LAM. Moreover, no obvious signal association of human teratogenicity with exposure to ETV or ADV was identified in fetuses during pregnancy. Nevertheless, owing to the limitations of a spontaneous reporting database, which inevitably contains potential biases, there is a pressing need for well-designed comparative safety studies to validate these results in clinical practice.

Safety and Efficacy of Tenofovir Alafenamide Fumarate in Early-Middle Pregnancy for Mothers With Chronic Hepatitis B

Background

Tenofovir alafenamide fumarate has been used in late pregnancy; however, no data exist regarding its safety and effectiveness in early and middle pregnancy for mothers with hepatitis B virus infection.

Aims

To design a prospective study to investigate the efficacy and safety of TAF in pregnant women with chronic HBV infection during early-middle pregnancy.

Methods

Pregnant women with active chronic hepatitis B who received tenofovir alafenamide fumarate during early and middle pregnancy were enrolled and followed up until 6 months postpartum. Infants received immunoprophylaxis. The primary endpoint was the safety of mothers and infants. The secondary endpoints were maternal hepatitis B virus DNA reduction at delivery and mother-to-child transmission rate.

Results

Among 98 mothers enrolled, 31 initiated tenofovir alafenamide fumarate in early pregnancy, and 57 in middle pregnancy. The mean (± standard deviation) age was 29.00 (±3.81) years. At delivery, 100% (98/98) of the mothers achieved hepatitis B virus DNA levels <200,000 IU/L. Ninety-eight infants were born, and none had congenital defects or malformations. All infants received hepatitis B virus immunoprophylaxis. The mother-to-child transmission rate was 0%. Growth parameters including body weight, height, and head circumference were comparable to the national standards for physical development. No severe adverse effects were reported in either mothers or infants. No severe liver function damage occurred in any of the mothers.

Conclusions

Initiating tenofovir alafenamide fumarate in early and middle pregnancy appears safe for both mothers and infants, and it is effective for controlling maternal disease as well as interrupting mother-to-child transmission.

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.

Influencing factors and necessity of post-vaccination serologic testing follow-up for HBsAg-positive mothers and their infants: A 5-year prospective study in Zhejiang Province, China (2016-2020)

In 2016, China officially proposed for the first time that infants born to HBsAg-positive mothers should be tested for HBsAg and anti-HBs 1-2 months after their third dose of HepB, also known as the post-vaccination serological testing programme. This study aimed to systematically evaluate the implementation and influencing factors of PVST to further reduce HBV infection risk in infants and improve the protective effect of HepB to the greatest extent. A prospective observational study was conducted to investigate the interruption of MTCT of hepatitis B. Univariate and multivariate analyses were applied to explore factors associated with the PVST follow-up rate among HBsAg-positive mothers and their infants. Additionally, bivariate analysis was performed on HBsAg and anti-HBs results in infants born to HBsAg-positive mothers. Here, the participation rate of PVST was 67.08% among 2120 pairs of positive mothers and infants. The HBsAg-positive rate among participants was 0.77%, whereas the anti-HBs positive rate was 96.84%, and both negative rates were 2.39%. Among infants with double negative results (34), only 15 completed three doses of HepB and PVST again, and 14 (93.33%) of which the antibody test results turned positive. Older mothers with high educational levels who reside in the local area were the most likely to PVST follow-up. The PVST programme is necessary to evaluate the HepB response status of newborns after vaccination. Moreover, revaccination for susceptible infants can effectively improve the MTCT-blocking rate of hepatitis B. Therefore, the scope of PVST projects in Zhejiang and China should be expanded.

Mother To Infant Transmission Of Hepatitis B Virus In The Face Of Neonatal Immunisation Is Not Necessarily Primary Vaccine Failure

BACKGROUND

Surveillance programmes undertaken in infants born to hepatitis B virus (HBV) infected mothers provide an opportunity to analyse virological markers from the neonate and early infancy. These data inform on mechanisms of HBV transmission and how available interventions can be better utilised for control of HBV infections arising at the mother/child interface.

METHODS

Retrospective analysis of HBV serological markers was undertaken in Dried Blood Spots collected from infants born to HBV-infected mothers. In addition, molecular analysis was performed in newborn blood spot cards, collected after birth, from infants identified as HBV-infected despite receiving prophylaxis.

RESULTS

Perinatal exposure could not account for all transmissions with at least one quarter (22%) of infants already infected in utero. All harboured a wild type HBsAg, with identical sequences noted in the neonatal and early infancy samples. In contrast, in infants infected perinatally (43%), selection of viruses harbouring amino acid changes in the HBsAg were common (80% of sequences) and divergent from the linked maternal sample.

CONCLUSION

Currently considered to represent vaccine failure, it is likely that a proportion of HBV infections result from in utero acquisition. These infections are unlikely to be susceptible to post-natal prophylaxis and current recommendations for maternal antiviral treatment may be too late to prevent transmission. Consideration should be given to the earlier use of antivirals during gestation to reduce the risk of intrauterine transmission together with completion of the immunisation schedule also to reduce the perinatal risk of HBV transmission.

2019 Chinese Clinical Practice Guidelines for the Prevention of Mother-to-child Transmission of Hepatitis B Virus

To develop the evidence-based guidelines for managing mother-to-child transmission of hepatitis B virus in China, a multidisciplinary guideline development group was established. Clinical questions were identified from two rounds of surveys on the concerns of first-line clinicians. We conducted a comprehensive search and review of the literature. A grading of recommendations' assessment, development, and evaluation system was adopted to rate the quality of evidence and the strength of recommendations. Recommendations were formulated based on the evidence, overall balance of benefits and harms (at individual and population levels), patient/health worker values and preferences, resources available, cost-effectiveness, and feasibility. Eventually, recommendations related to 13 main clinical concerns were developed, covering diagnostic criteria, treatment indications, antiviral therapy choice, timing to initiate and discontinue treatment, immunoprophylaxis strategy at birth, and how to deal with special situations, such as unintended pregnancy, assisted reproduction, and breastfeeding. The guidelines are intended to serve as guidance for clinicians and patients, to optimize the management of majority of pregnant women who are positive for hepatitis B surface antigen. Guideline registration: International Practice Guide Registration Platform (IPGRP-2018CN040).

Tenofovir for prevention of mother to child transmission of hepatitis B in migrant women in a resource-limited setting on the Thailand-Myanmar border: a commentary on challenges of implementation

BACKGROUND

The aim of this manuscript is to highlight challenges in the implementation of maternal tenofovir disoproxil fumarate (tenofovir) for prevention of mother to child transmission (PMTCT) of hepatitis B virus (HBV) in resource limited setting. Current preventive strategies in resource-limited settings fail mainly due to prohibitive costs of hepatitis B immunoglobulin (HBIG) and a high proportion of homebirths, meaning both HBIG and hepatitis B birth dose vaccine are not given. A new strategy for PMTCT without the necessity of HBIG, could be daily tenofovir commenced early in gestation. Implementation challenges to early tenofovir for PMTCT can provide insight to elimination strategies of HBV as the burden of disease is high in resource-limited settings.

METHODS

Challenges encountered during implementation of a study of tenofovir for PMTCT before 20 weeks gestation in rural and resource-limited areas on the Thailand-Myanmar border were identified informally from trial study logbooks and formally from comments from patients and staff at monthly visits. ClinicalTrials.gov Identifier: NCT02995005.

MAIN BODY

During implementation 171 pregnant women were hepatitis B surface antigen (HBsAg) positive by point of-care test over 19 months (May-2018 until Dec-2019). In this resource-limited setting where historically no clinic has provided tenofovir for PMTCT of HBV, information provided by staff resulted in a high uptake of study screening (95.5% (84/88) when offered to pregnant women. False positive point-of-care rapid tests hinder a test and treat policy for HBV and development of improved rapid tests that include HBeAg and/or HBV DNA would increase efficiency. Integrated care of HBV to antenatal care, transport assistance and local agreements to facilitate access, could increase healthcare at this critical stage of the life course. As safe storage of medication in households in resource-limited setting may not be ideal, interactive counseling about this must be a routine part of care.

CONCLUSION

Despite challenges, results from the study to date suggest tenofovir can be offered to HBV-infected women in resource-limited settings before 20 weeks gestation with a high uptake of screening, high drug accountability and follow-up, with provision of transportation support. This commentary has highlighted practical implementation issues with suggestions for strategies that support the objective of PMTCT and the World Health Organization goal of HBV elimination by 2030.