Towards complete eradication of hepatitis B infection from perinatal transmission: review of the mechanisms of in utero infection and the use of antiviral treatment during pregnancy

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.

Prevalence of HIV and hepatitis B virus among pregnant women in Luanda (Angola): geospatial distribution and its association with socio-demographic and clinical-obstetric determinants

Background

HIV and HBV infections remain responsible for high rate of morbidity and mortality in many African Countries, affecting women and newborns. This study aims to analyze the spatial pattern of HIV and HBV infections in pregnant women in Luanda, Angola, and the statistical association between HIV and HBV and socio-economic characteristics, hygiene, and health status.

Methods

Detection of anti-HIV antibodies (total anti-HIV-1, anti-HIV-2 and HIV-1 p24 antigen) and Hepatitis B antigens (HBsAg, HBeAg) and antibodies (anti-HBc Total II, HBc IgM, Anti-HBsT II) was performed by Enzyme Linked Fluorescent Assay (ELFA) in serum samples of 878 pregnant women attended at the Lucrecia Paim Maternity Hospital (LPMH). Data were collected by questionnaire after written consent, and spatial distribution was assessed through a Kernel Density Function. The potential risk factors associated with HIV HBV infection were evaluated using bivariate and multivariate binomial logistic regression analysis.

Results

Anti-HIV antibodies were positive in 118 samples (13.4%) and HBV infection were positive in 226 (25.7%). The seroprevalence of HIV/HBV coinfection was of 6.3%. The results showed that the seroprevalence of HBV was similar in most municipalities: 25.8% in Belas; 26.6% in Viana; 27.6% in Luanda; 19.2% in Cacuaco; and 15.6% Cazenga. For HIV, the seroprevalence was also close ranges among the municipalities: 10.0% in Belas; 14.5% in Viana 14.9% in Luanda and 12.5% in Cazenga. However, the seroprevalence in municipality of in Cacuaco was lower (5.8%) and bivariate and multivariate analysis showed a lower risk for HIV in this area (OR 0.348, CI 0.083–0.986; OR 0.359, CI 0.085–1.021). The multivariate analysis had also showed a significant increased risk for HIV in women with 2 or 3 births (OR 1.860, CI 1.054–3.372).

Conclusions

Our results underlined the need to improve the screening and clinical follow-up of HIV and HBV in Angola, as well the educational campaigns to prevent not only the morbidity and mortality associated with these diseases, but also their transmission, mainly in women in reproductive age and pregnant, encouraging the pre-natal consultations in order to avoid mother-to-child transmission.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-021-01698-7.

Knowledge, perception and expectation of management of hepatitis B infection among pregnant hepatitis B carriers in Hong Kong

Lack of awareness regarding the risk of hepatitis B virus (HBV) infection and the interventions available during pregnancy among the pregnant carriers may influence their willingness and adherence to the management. This study assessed the knowledge, perception and expectation of HBV infection among pregnant HBV carriers in Hong Kong. A prospective multicentre cross-sectional questionnaire study was carried out between August 2019 and April 2021. The general knowledge on HBV, perception and expectation, and interventions to reduce vertical transmission were questioned. Obtaining ≥70% correct answers was defined as having sufficient knowledge. 422 (82.7%) were known carriers. Only 18.4% of women had sufficient overall knowledge. The correct answer rates and percentage of sufficient knowledge were statistically lower for HBV knowledge specific to pregnancy compared with general knowledge (42.5% vs. 58.5%, p < 0.001; 8.8% vs. 30.2%, p < 0.001 respectively). Multiple logistic regression showed higher education and receiving HBV medical care within a year prior to pregnancy were associated with sufficient overall (OR 3.46; 95% CI 2.05-5.83 and OR 2.76; 95% CI 1.62-4.7, p < 0.001), and general knowledge (OR 2.86; 95% CI 1.81-4.51 and OR 2.14; 95% CI 1.33-3.44, p < 0.05). 298 (58.4%), 357 (70.0%) and 150 (29.4%) women believed they should receive care by obstetrician, hepatologist or general practitioner respectively. 46.9% did not want to initiate antiviral treatment due to the cost, perceived teratogenicity and maternal side effects. The knowledge of HBV among pregnant carriers in Hong Kong was poor despite the majority of them being aware of their carrier status prior to the pregnancy.

Income Inequalities in Hepatitis B Vaccination and Willingness to Pay Among Women of Reproductive Age in Hanoi, Vietnam

BACKGROUND

Hepatitis B virus (HBV) infection is endemic in Vietnam and can be transmitted from mother to child. Vaccination of women of reproductive age (WRA) can reduce this transmission. Because adult HBV vaccination in Vietnam follows a fee-for-service model, research is needed to determine the effect of household income on willingness to pay (WTP) to ensure equitable access to the vaccine.

METHODS

A cross-sectional study was performed in Hanoi, Vietnam, in April 2018, among WRA. Questionnaires were administered to assess household income, HBV history, vaccination status, vaccine awareness, and WTP for the vaccine. Multivariable logistic and interval regression were performed to assess the impact of household income on WTP for HBV vaccine.

RESULTS

This study found that 62.3% of all participants were willing to pay for the HBV vaccine with no differences in WTP across income quintiles. There were significant differences among household income levels in awareness of HBV vaccination and WTP amount beyond US$4.50 with the lowest awareness and WTP amount among women from the lowest income quintiles.

CONCLUSIONS

Our data suggest the need to subsidize HBV vaccination for low-income women to ensure more equitable access to HBV vaccination. We propose that a sliding-scale payment method may be an effective strategy in light of limited funding to support vaccination expansion. An education campaign focusing on lower-income households should also be implemented in conjunction with this program. Further research would be required to evaluate consumer acceptance of this payment scheme and to develop an appropriate sliding scale to maximize vaccine uptake.

Distribution Evaluation of Tenofovir in the Breast Milk of Mothers With HBeAg-Positive Chronic HBV Infection After Treatment With Tenofovir Alafenamide and Tenofovir Disoproxil Fumarate by a Sensitive UPLC-MS/MS Method

Tenofovir alafenamide (TAF) is a novel prodrug of tenofovir (TFV) that has been approved for the treatment of chronic hepatitis B virus (HBV) infection. It has greater plasma stability and more favorable renal safety than tenofovir disoproxil fumarate (TDF), the first approved oral prodrug of TFV. However, the distribution of TFV in the breast milk of mothers treated with TAF is still unclear. In this study, sixteen participants with chronic HBV infection were enrolled and received antiretroviral therapy with 25 mg of TAF or 300 mg of TDF daily from 24 to 28 weeks of gestation until the 4th week postpartum. For the first time, the distribution of TFV in the breast milk of mothers with chronic HBV infection treated with TAF and its difference from TDF were evaluated by using a sensitive UPLC-MS/MS method. Chromatographic separation was achieved on a Waters ACQUITY UPLC BEH C18 column (1.7 µm 2.1 × 100 mm). Mass spectrometry analysis was performed in positive electrospray ionization mode and multiple reaction monitoring (MRM) conditions of transitions m/z 288.1→176.2 for TFV. This method was linear from 0.5 to 500 ng/ml. Surprisingly, on the third postpartum day, the median Cmax of TFV in the breast milk was much higher in the mothers treated with TAF (101.2 ng/ml) than TDF (21.6 ng/ml) at a similar Tmax of 4 h. Accordingly, the median AUC0-8 value was 755.6 ng h/mL in the mothers taking TAF, which was at a 5-fold higher level than TDF. The concentration of TFV in the breast milk of mothers in both groups decreased with increasing lactation time. These data indicated that there was a relatively higher exposure of TFV in the breast milk of mothers taking TAF, despite the lower dosage compared to TDF. This study provides support for further evaluating the safety of breastfeeding after the administration of TAF and TDF.

Hepatitis B Virus Infection in Pregnancy: An Update on Evidence-Based Management

Importance

Vertical hepatitis B virus (HBV) transmission is the important route of chronic HBV infection. Although infant immunoprophylaxis is effective, a significant number of infants still become infected, most are associated with intrauterine infection. New evidences support intrauterine treatment in cases of high risk.

Objective

The aim of this study was to review the current evidences and recommendations for management of HBV infection in pregnancy.

Evidence Acquisition

Original research articles, review articles, and guidelines were reviewed.

Results

The management can be summarized as follows: (1) all pregnant women should be screened for hepatitis B surface antigen (HBsAg) and antibody to HBsAg. High-risk HBsAg-negative pregnant women without immunity should be vaccinated during pregnancy. (2) HBsAg-positive pregnant women should undergo further workup for liver status and indicative factors for immunoprophylaxis failure. (3) Pregnant women should be treated with HBV DNA levels greater than 200,000 IU/mL or 6 log copies/mL. (4) Antiviral drug should be started around 28 to 32 weeks. The first-line drug is tenofovir disoproxil fumarate. (5) Delivery route should be chosen based only on obstetric indications. (6) Breastfeeding is not contraindicated because it does not increase the risk of transmission in neonates with HBV vaccine and immunoglobulin administration. (7) Neonates born to HBsAg-positive mothers should receive HBV vaccine and immunoglobulin after birth as soon as possible. (8) Follow-up of the mothers and neonates is important. Beware of hepatitis flare after birth and after antiretroviral drug discontinuation; alanine transaminase assessment every 1 to 3 months until 6 months is suggested. Also, the schedule of infant vaccination and follow-up of serologic testing at 9 to 12 months old is needed.

Premature Rupture of Membranes with Concurrent Viral Infection

Treatment of viral infections is geared toward ameliorating maternal symptoms and minimizing perinatal transmission. Multidisciplinary teams often are required to manage sequelae due to viral diseases in patients with preterm premature rupture of membranes (PPROM). although data are scarce regarding the antepartum management of common viruses in PPROM, essential principles may be extrapolated from national guidelines and studies in gravid patients. The well-established risks of prematurity are weighed against the often unclear risks of vertical transmission.

Prevalence of hepatitis B virus infection in pregnant women with and without HIV in Jos, Nigeria

OBJECTIVE

To compare the prevalence of hepatitis B virus (HBV) in pregnant women with and without human immunodeficiency virus (HIV) in Jos, Nigeria.

METHODS

This comparative cross-sectional study of pregnant women was undertaken between 1 November 2017 and 30 April 2018. Informed consent was obtained, demographic data and predictors for HBV were collected, and all women were screened for HIV and HBV. Descriptive statistics and multivariate analyses using STATA Version 15 were performed.

RESULTS

Of 3238 women enrolled, 12.6% and 7.2% of those with and without HIV had HBV, respectively (P = 0.01). Women with HIV, higher parity [adjusted odds ratio (aOR) 0.68, P < 0.01], lower gestational age (aOR 1.04, P < 0.01) and without prior HBV vaccination (aOR 0.40, P < 0.01) were significantly more likely to have HBV infection.

CONCLUSIONS

Among pregnant women, the prevalence of HBV was higher among those with HIV. Predictors of HBV included being multigravida or grand-multigravida, registration for antenatal care before 20 weeks of gestation, and no prior HBV vaccination. In settings with endemic HBV and HIV, integration of effective HBV and HIV prevention services could greatly decrease the transmission and prevalence of HBV.

Tenofovir disoproxil fumarate for prevention of mother-to-child transmission of hepatitis B virus: A systematic review and meta-analysis of randomised control trials

Hepatitis B virus (HBV) infection caused by mother-to-child transmission (MTCT) continues to pose challenges to global health. This study aimed to assess the efficacy and safety of tenofovir disoproxil fumarate (TDF) for preventing HBV MTCT. PubMed and the Cochrane Central Register of Controlled Trials were searched through August 2020. Randomised controlled trials (RCTs) were selected that evaluated the efficacy and safety of TDF for preventing MTCT of HBV compared with the standard of care, placebo or other HBV therapies. The primary outcomes were HBV MTCT rate and maternal HBV DNA level. Secondary outcomes were infant and maternal safety outcomes. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines, and prospectively registered on PROSPERO (CRD42020186275). Of 240 citations, three RCTs that involved 651 participants were included. The pooled result showed that TDF can reduce the risk of HBV MTCT after 6 months postpartum by 80% (risk ratio [RR] 0.2, 95% confidence interval [CI 0.06-0.7], n = 584) with low heterogeneity (I²  = 0%). TDF demonstrated HBV DNA suppression at delivery, though there was heterogeneity among individual studies (RR 0.13, 95% CI [0.08-0.20] and (RR 0.36, 95% CI [0.27-0.49]). Maternal and infant safety outcomes were comparable among treated and untreated mothers and infants born to them. The quality of evidence varied from high to very low. There is evidence that TDF effectively interrupted MTCT of HBV and suppressed HBV DNA level. Available studies on safety are very limited and heterogeneous, emphasising the need for additional RCTs with complete safety indicators.

Prevention strategies of mother-to-child transmission of hepatitis B virus (HBV) infection

Chronic hepatitis B virus (HBV) infection caused by mother-to-child transmission (MTCT, also known as vertical transmission) during the perinatal period is a major public health problem worldwide. Despite the availability of the combined active-passive immunization with a hepatitis B vaccine and hepatitis B immunoglobulin after birth, about 9% of newborns are still infected with HBV, especially those born to hepatitis B e antigen (HBeAg)-positive mothers. Currently, the management of HBV infection during pregnancy remains controversial. This article briefly reviews the recent advances in the epidemiology of HBV, immunization against it, and management strategies in the third trimester.

Intra-host diversity of hepatitis B virus during mother-to-child transmission: the X gene may play a key role in virus survival in children after transmission

Mother-to-child transmission of hepatitis B virus (HBV) is the main route of transmission in Asia, and characterization of HBV quasispecies is needed to further understand virus evolution and adaptation. To understand changes in HBV during mother-to-child transmission, we enrolled nine pairs of mothers and children in the study, including a set of twins. Three groups were infected with HBV genotype C, and six groups were infected with HBV genotype B. The full-length HBV genome was amplified by PCR from serum samples before antiviral treatment, the whole viral genomes from each pair were sequenced, and the complexity and diversity of the quasispecies were analyzed. The entropy of transmitted HBV in children was found to be lower than their mothers, suggesting that there was a bottleneck effect during HBV transmission from the mother to the child. Selective evolution was shown by calculating πN and πS in the whole genomes, and the highest values were obtained for the X gene, which plays a role in viral replication and immune escape. All genotype C patients and only one genotype B pair had a πN/πS greater than 1 ratio, indicating that positive selection had occurred. In addition, quasispecies were found to be different between the twin children despite having the same mother, indicating that virus evolution is host-specific.

Hepatitis B and Pregnancy: Virologic and Immunologic Characteristics

The hepatitis B virus (HBV) is an important human pathogen. Unvaccinated infants infected through mother-to-child transmission (MTCT) are at >95% risk of developing serum hepatitis B surface antigen-positive chronic hepatitis B (CHB). Despite complete passive-active HBV immunoprophylaxis, approximately 10% of infants born to mothers who are highly viremic develop CHB, and thus maternal treatment with nucleos(t)ide analogs (tenofovir disoproxil fumarate, lamivudine, or telbivudine) is recommended in the third trimester of pregnancy to reduce MTCT risk. Viral rebound usually occurs after stopping treatment and, in the context of maternal immunologic reconstitution postpartum, can also precipitate host immune-mediated hepatic (biochemical) flares. In this article, we review the epidemiology of HBV MTCT, discuss management and potential mechanisms of HBV vertical transmission, and highlight recent studies on virologic and immunologic aspects of hepatitis B in pregnancy and postpartum.

The changing epidemiology of hepatitis B and C infections in Nanoro, rural Burkina Faso: a random sampling survey

BACKGROUND

This study sought to provide up-to-date hepatitis B (HBV) and C (HCV) seroprevalence in rural Burkina Faso decade after hepatitis B vaccine was introduced in the national immunization scheduled for children.

METHODS

In 2018, a community-based, random sampling strategy with probability proportional to population size was conducted in Nanoro to investigate the prevalence of viral hepatitis in children and their mothers. Sociodemographic, vaccination history and risk factors were assessed by interview and health books. HBsAg rapid tests were done by finger prick and Dried Blood Spots (DBS) were collected for hepatitis seromarkers by chemiluminescence enzyme immunoassay. Positive samples underwent confirmatory PCR and phylogenetic analysis.

RESULTS

Data were presented on 240 mother-child pairs. HBsAg Prevalence was 0.8% in children and 6.3% in mothers. Hepatitis B core antibody positivity was 89.2% in mothers, 59.2% in children and was associated with age, sex and scarification. Hepatitis B surface antibodies prevalence was 37.5% in children and 5.8% in mothers. Good vaccination coverage was limited by home delivery. Phylogenetic analysis of HBV strains based on full genome sequences (n = 7) and s-fragment sequences (n = 6) revealed genotype A, E, and recombinant A3/E. Viral genome homology was reported in one mother-child pair. Anti-HCV prevalence was 5.4% in mothers, 2.1% in children and strains belonged to genotype 2.

CONCLUSIONS

In Nanoro, HBsAg prevalence was low in children, intermediate in mothers and mother-to-child transmission persists. Home delivery was a limiting factor of Hepatitis B vaccination coverage. HBV genotype E was predominant and genotype A3/E is reported for the first time in Burkina Faso.

[Seroprevalence and factors associated with viral hepatitis B among pregnant women in Parakou, Republic of Benin]

L'objectif est de déterminer la séroprévalence et les facteurs associés à l'hépatite virale B chez les gestantes au Centre Hospitalier Universitaire Départemental du Borgou (CHUD-B). Il s'est agi d'une étude transversale à visée descriptive et analytique avec recueil prospectif des données. Elle a porté sur les gestantes suivies et/ou ayant accouchées au CHUD-B du 1^er avril 2017 au 30 juin 2017. Étaient incluses, celles ayant données leur consentement à participer à l'étude. Les variables étudiées étaient les données sociodémographiques des gestantes et le résultat de l'AgHBs. La recherche de l'AgHBs sur les prélèvements sanguins des gestantes était faite par un test biologique de diagnostic rapide. Les résultats positifs étaient confirmés par la technique ELISA. Deux cent quatorze (214) gestantes étaient incluses dans l'étude. Leur âge moyen était de 26,73 ± 5,68 ans. L'âge médian de la grossesse en cours était de 31 semaines d'aménorrhée (SA) avec des extrêmes de 4 SA et 42 SA. Parmi elles, 30 femmes étaient dépistées positives à l'AgHBs soit une prévalence de 14,02%. Les facteurs associés à ce portage étaient la pratique des scarifications, l'antécédent personnel d'ictère et les antécédents familiaux d'hépatite virale B. La séroprévalence de l'hépatite virale B chez les gestantes au CHUD-B est élevée ce qui rend bien compte du problème majeur de santé publique que pose l'infection par le virus de l'hépatite B sous nos cieux.

Efficacy of antepartum administration of hepatitis B immunoglobulin in preventing mother-to-child transmission of hepatitis B virus

The aim of this study was to investigate the efficacy of antepartum administration of three doses of hepatitis B immunoglobulin (HBIG) in interrupting mother-to-child transmission (MTCT) of hepatitis B virus (HBV). In this trial, a total of 728 HBeAg-positive pregnant women with chronic HBV infection who had an HBV DNA level higher than 6log₁₀  copies/mL were enrolled. They were divided into three groups based on individual preference. Subjects in group A and group B received 200 IU (unit) HBIG and 400 IU (unit) HBIG intramuscularly once a month at the third, second and first month before delivery, respectively. Subjects in the control group (C) received no special treatment. All the infants received passive-active immunoprophylaxis. The HBsAg-positive rate of all infants at 7-12 months of age was 5.1% (37/728). Specifically, the HBsAg-positive rate of infants was comparable in all three groups (5.3% vs 5.1% vs 5%, P = 0.988). No significant difference was found in anti-HBs levels between the infants aged 7-12 months in the three groups (P = 0.469). HBV DNA levels of the umbilical cord blood in the HBV-infected group were higher than those in the uninfected group (5.2 vs 3.4log₁₀  copies/mL, P < 0.001), and these with family history of HBV infection were also higher (45.9% vs 28.5%, P = 0.034). To conclude, administration of passive-active immunoprophylaxis to infants contributed to effective prevention of the MTCT of HBV; extra antepartum administration of HBIG during pregnancy could not decrease the rate of MTCT or increase the anti-HBs levels of infants born to HBsAg-positive mothers with HBV DNA higher than 6log₁₀  copies/mL.

Optimal timing of hepatitis B virus DNA quantification and clinical predictors for higher viral load during pregnancy

INTRODUCTION

Authorities publish recommendations on the hepatitis B virus (HBV) viral load threshold to initiate antiviral treatment but the timing of quantification during pregnancy is not well defined. HBV DNA levels in pregnancy women at 28-30 weeks predict the risk of immunoprophylaxis failure. This study compared and evaluated the correlation between HBV DNA levels before 22 and 28-30 weeks' gestation. Clinical predictive factors for HBV DNA >6, 7 and 8 log₁₀  IU/mL were studied.

MATERIAL AND METHODS

A retrospective analysis of HBV DNA levels of women <22 and 28-30 weeks of gestation was carried out in 352 pregnant HBV carriers. HBV DNA was examined using the COBAS TaqMan HBV Monitor Test coupled with the COBAS Ampliprep extraction system (Both Roche Diagnostics, Branchburg, NJ, USA).

RESULTS

A strong positive correlation was found between the viral loads of women <22 weeks (mean 16.7 weeks) and 28-30 weeks of gestation, which was independent of the viral load level and gestational age of quantification (r = 0.942, P < 0.001). Univariate analysis showed that positive hepatitis B e antigen (HBeAg), maternal age <35 years old and body mass index ≤21 kg/m² were associated with a higher mean viral load at 28-30 weeks of gestation (P < 0.05). These factors were also associated with a higher chance of viral load >6, 7 and 8 log₁₀  IU/mL at 28-30 weeks (P < 0.05). In multiple regression analysis, only the viral load of <22 weeks and positive HBeAg remained predictive of a higher mean viral load at 28-30 weeks of gestation (P < 0.05). The receiver operating characteristic curve showed that the HBV DNA of <22 weeks was an excellent predictor for different viral load cut-offs at 28-30 weeks. The area under curve was 0.986, 0.998 and 0.994 for viral load 6, 7 and 8 log₁₀  IU/mL, respectively.

CONCLUSIONS

HBV DNA quantification should be performed before 22 weeks of gestation. Viral load cut-offs similar to those at 28 weeks can be used to determine immunoprophylaxis failure at earlier gestation. Maternal positive HBeAg status was associated with a higher chance of viral load >6, 7 or 8 log₁₀  IU/mL.

Prevention of perinatal hepatitis B virus transmission

PURPOSE

Chronic hepatitis B virus (HBV) infection remains endemic and continues to cause significant morbidity and mortality. It is a global health issue and the World Health Organization aims to eradicate HBV by 2030. Since vertical transmission accounts for the majority of chronic HBV infection, pregnancy offers an excellent opportunity to achieve complete HBV eradication by providing effective immunization of the offspring.

METHODS

We reviewed recent publications identified from PubMed database using a combination of the relevant keywords for HBV, pregnancy, vertical transmission, immunoprophylaxis failure and antiviral treatment.

RESULTS

We summarized the evidence of factors associated with, and measures to reduce and prevent maternal to child transmission, including the use of antiviral treatment during pregnancy to prevent immunoprophylaxis failure. Evidence suggested that highly viremia mother can be offered antenatal antiviral treatment to prevent immunoprophylaxis failure. We elaborated the viral load threshold to start maternal antiviral treatment and the importance of timely neonatal vaccination. A clinical algorithm to manage HBV carriers during pregnancy was proposed.

CONCLUSION

Eradication of HBV is achievable with optimal management of HBV carriers, especially during pregnancy by interruption of vertical transmission. Routine antenatal screening and neonatal immunoprophylaxis remain the key measures to reduce the global HBV burden, and additional antenatal antiviral treatment could further minimize the chance of persistent infection in newborns.

Estimating Annual Births to Hepatitis B Surface Antigen-Positive Women in the United States by Using Data on Maternal Country of Birth

OBJECTIVE

A national estimate of births to hepatitis B surface antigen (HBsAg)-positive women can help public health programs plan surveillance, educational, and outreach activities to improve identification and management of at-risk women and infants. Stratifying mothers by country of birth allows for the application of region-specific HBsAg prevalence estimates, which can more precisely estimate the number of at-risk infants. The objective of our study was to estimate the number of births to HBsAg-positive women in the United States with more granularity than previous models.

METHODS

We developed a model that incorporated maternal country of birth (MCOB) and updated HBsAg prevalence estimates. We assessed birth certificate data by MCOB, and we stratified US-born mothers by race/ethnicity, US territory-born mothers by territory, and non-US-born mothers by region. We multiplied and summed data in each subcategory by using HBsAg prevalence estimates calculated from the 2009-2014 National Health and Nutrition Examination Surveys or Perinatal Hepatitis B Prevention Program. We compared the findings of our MCOB model with a race/ethnicity model.

RESULTS

In 2015, an estimated 20 678 infants were born to HBsAg-positive women in the United States, representing 0.5% of all births. Births to US-born and non-US-born women comprised 77.2% and 21.5% of all births, respectively, and 40.1% and 57.9% of estimated births to HBsAg-positive women, respectively. The estimated contribution of births to HBsAg-positive women varied by MCOB region, from 4 (0.03%) infants born to women from Australia/Oceania to 5795 (28.0%) infants born to women from East Asia. Our MCOB model estimated 5666 fewer births to HBsAg-positive women than did the race/ethnicity model.

CONCLUSIONS

As global vaccine programs reduce HBsAg prevalence, the MCOB model can incorporate evolving HBsAg prevalence estimates for women from various regions of the world.

Pattern and predictors of medical care received by hepatitis B carriers during pregnancy and after delivery

OBJECTIVE

The objective of the study is to evaluate the pattern and predictors of medical care received by hepatitis B virus (HBV) carriers during pregnancy and after delivery in Hong Kong.

STUDY DESIGN

The study is a retrospective analysis.

METHODS

Pregnant HBV carriers and their infants were followed up for 9-12 months after delivery. Face-to-face interviews were conducted to investigate what medical care they received for HBV before, during and after pregnancy.

RESULTS

Data were available for 412 HBV carriers. A total of 375 (91.0%) women were known HBV carriers before pregnancy. Routine antenatal screening picked out the remaining 37 (9.0%) HBV carriers; these women were younger, more likely to be smokers and had a lower level of education (P < 0.05) than known HBV carriers. In total, 356 of 412 (86.4%) HBV carriers did not receive any medical care for HBV during pregnancy. Known HBV carrier status, history of medical check-up and the use of antiviral treatment before pregnancy were significant predictors for HBV medical care during pregnancy (P < 0.05). The results show that 217 of 412 (52.6%) HBV carriers did not receive medical care for HBV after delivery. HBV medical care before pregnancy, use of antiviral treatment before pregnancy and a higher level of education were significant predictors for postpartum HBV medical care (P < 0.05). Multivariate analysis showed that HBV medical care before pregnancy (odds ratio [OR], 7.73; 95% confidence interval [CI], 3.21-18.65; P < 0.001) and the use of antiviral treatment (OR, 5.02; 95% CI, 1.41-17.81; P = 0.013) were associated with medical care during pregnancy. Medical care before pregnancy was also associated with postpartum HBV medical care (OR, 5.05; 95% CI, 3.29-7.51; P < 0.001).

CONCLUSIONS

A significant proportion of HBV carriers did not receive HBV-related medical check-ups during and after pregnancy in Hong Kong despite the majority being aware of their carrier status. Medical care before pregnancy predicted antenatal and postpartum HBV medical care.

Hepatitis B Infection among Parturient Women in Peri-Urban Ghana

Global evidence suggests that hepatitis B viral (HBV) infection is endemic in Africa and perinatal transmission remains one of the most important modes of HBV transmission in this area. This cross-sectional survey examined the seroprevalence and knowledge of hepatitis B among pregnant women attending antenatal clinic (ANC) in a mission hospital in Ghana. Systematic sampling technique was used to recruit 196 pregnant women. The level of statistical significance was set at 0.05 alpha level. The hepatitis B prevalence estimate (hepatitis B surface antigen) was 10.2% (N = 20) and all of the participants were aware of HBV infection. Majority cited media (radio) as their main source of information. Approximately 86% of the participants (N = 168) associated HBV infection with a curse and 88.8% (N = 174) indicated witches and wizards as possible causes of the infection. Those with higher level of school education had high hepatitis B knowledge score (P < 0.01). Implementation of a health education program on the route of hepatitis B transmission is required in the study setting. Also, inclusion of hepatitis B education as part of ANC activities will enable HBV-positive pregnant women to appreciate the need for hepatitis B vaccination of their newborns at birth.

The effect of rupture of membranes and labour on the risk of hepatitis B vertical transmission: Prospective multicentre observational study

OBJECTIVE

To evaluate the effect of rupture of membranes and labour on the risk of hepatitis B virus (HBV) vertical transmission.

STUDY DESIGN

A prospective multicentre observational study was carried out in Hong Kong between 2014-2016. Pregnant HBV carriers were recruited. The duration of rupture of membranes, labour and mode of delivery were collected prospectively. HBV DNA was examined at 28-30 weeks of gestation. All newborns received standard HBV vaccination and immunoglobulin. Hepatitis B surface antigen of infants was tested at 9-12 months of age.

RESULTS

641 pregnancies were recruited and analyzed. No statistically significant difference was found in gravida, parity, gestational age at delivery, mode of delivery, duration of rupture of membranes, duration of labour, preterm delivery, preterm rupture of membranes or birth weight (p > 0.05). Subgroup analysis in viral load > 7log₁₀IU/ml and 8log₁₀IU/ml also did not find a significant association between duration of rupture of membranes and labour with immunoprophylaxis failure.

CONCLUSIONS

Duration of rupture of membranes and labour would not affect the risk of HBV vertical transmission in infants following standard HBV vaccination and hepatitis B immunoglobulin administration.

Heterogeneity of Hepatitis B Infection Among Pregnant Asian American and Pacific Islander Women

INTRODUCTION

Perinatal transmission of hepatitis B virus among Asian Americans and Pacific Islanders is a key driver of racial health disparities in liver cancer and mortality in the U.S. This study documents the prevalence of hepatitis B virus infection among pregnant women across racial/ethnic groups and among Asian Americans and Pacific Islanders to assess the need for intervention, and then identifies the individual correlates of hepatitis B virus infection among Asian American and Pacific Islander pregnant women.

METHODS

Using the 2014-2015U.S. birth rate population data, this study estimates a series of logistic regression models to examine the associations between individual-level correlates and hepatitis B virus infection among Asian American and Pacific Islanders pregnant women. Data were analyzed in July 2017.

RESULTS

Among Asian American and Pacific Islander pregnant women, Chinese American mothers are ten times more likely to experience hepatitis B virus infection than are Asian Indian and Japanese American mothers. Foreign-born mothers are significantly more likely to experience hepatitis B virus infection during pregnancy than those of their U.S.-born counterparts. Maternal SES characteristics are important correlates of hepatitis B virus infection among pregnant women.

CONCLUSIONS

Studies must disaggregate the pan-ethnic Asian American and Pacific Islander category to examine the health and health disparities of Asian Americans and Pacific Islanders. Given the heterogeneity of hepatitis B virus infection prevalence among Asian American and Pacific Islander pregnant women, the effectiveness of prevention and intervention programs depends on careful consideration of ethnicity in conjunction with group-specific factors.

Effect of antiviral therapy in reducing perinatal transmission of hepatitis B virus and maternal outcomes after discontinuing them

BACKGROUND/AIMS

There have been numerous efforts to reduce mother-to-child transmission (MTCT) of hepatitis B virus (HBV) with antiviral agents during pregnancy. However, there are limited data regarding the outcomes of pregnant women after delivery. This study was performed to evaluate the efficacy of antiviral agents in preventing MTCT of HBV and maternal long-term outcomes.

METHODS

The HBV-infected pregnant women treated with antiviral agents to prevent MTCT were retrospectively reviewed. Forty-one pregnant women who received telbivudine or tenofovir during late pregnancy (28-34 week) were analyzed. Hepatitis B virus surface antibody (HBsAb) positivity was tested in 43 infants after 7 months of birth. Eleven mothers were followed >1 year after delivery.

RESULTS

The mean HBV DNA titer before antiviral therapy was 8.67 (6.60-9.49) log copies/mL, and the median age at delivery was 32 years (range, 22-40). Eleven patients were treated with tenofovir and 30 with telbivudine. The median duration was 57 days (range, 23-100), and the median HBV DNA titer at birth was 5.06 log copies/mL (range, 2.06-6.50). Antiviral treatments were associated with significant HBV DNA reduction (P<0.001). Among 43 infants (two cases of twins), HBsAb was not detected in two, subsequently confirmed to have HBV infection. Biochemical flare was observed in two of 11 mothers followed >12 months, and an antiviral agent was administered.

CONCLUSION

Antiviral treatment during late pregnancy effectively reduced MTCT. Long-term follow-up should be required in such cases. In addition, given that maternal biochemical flare occurred in 18% of mothers, re-administration of antiviral agents might be required.

Assessment of the prevalence of vertical hepatitis B transmission in two consecutive generations

INTRODUCTION

Hepatitis B is an important public health problem in the world and one of the forms of contagion would be through vertical transmission. Precose diagnosis allows the adoption of prophylaxis measures, which results in prevention in more than 90% of cases.

OBJECTIVE

To describe the prevalences of vertical transmission and compare two generations (mother/patient and patient/child).

METHOD

This was a cross-sectional study, which included 101 patients. The interviews were performed through the application of the instrument of data collection and information of the physical file before the medical consultation.

RESULTS

The mean ± SD of age was 50.9 ± 13.1 years, the male gender predominated, with 56.4% of the patients, and the predominance was white, with 43.6%. Vertical transmission between mother and patient occurred in 17.8% and between patient and child, in 7.9%. In all of the eight cases of vertical transmission, the diagnosis was after the birth of children infected with HBV, and in 3/8 (37.5%), there was more than one case of infection by this mechanism per patient, totaling 13 children with the disease.

CONCLUSION

There was a reduction in vertical transmission, showing that preventive measures were effective.

Hepatitis B At-Birth Dose Vaccine: An Urgent Call for Implementation in Ghana

Globally, approximately two billion people are infected with the Hepatitis B virus with attributable death estimated at about half a million people annually across the globe. Chronic hepatitis B infection is also an important public health problem in Ghana. The main mode of transmission in endemic regions is the perinatal route. Mother-to-child transmission can be reduced by antiviral therapy especially in the last trimester and adherence to the national immunization schedule. The World Health Organization recommends to add the birth dose vaccine to the current expanded program on immunization (EPI) in all countries but especially for endemic regions. The evidence for the efficacy of the birth dose HBV vaccine is overwhelming and there is an urgent need for its introduction into the current EPI schedule in Ghana.

Management of Chronic Hepatitis B in Pregnancy

Chronic hepatitis B virus (HBV) infection due to mother-to-child transmission during the perinatal period remains an important global health problem. Despite standard passive-active immunoprophylaxis with hepatitis B immunoglobulin and hepatitis B vaccine in neonates, up to 8.5% of newborns still acquire HBV infection. Thus, management of chronic HBV during pregnancy and strategies to prevent mother-to-child transmission are important steps in eradicating or reducing the global burden of chronic HBV infection. To date, the management of HBV infection in pregnancy still needs careful attention because of some controversial aspects, including the influence of pregnancy on the course of HBV replication, safety of antiviral prophylaxis with nucleus(t)ide analogs, postpartum flares of hepatitis after delivery, and the safety of breastfeeding. In this review, we highlight these important issues of preventive strategies in the perinatal period.

Prevalence of Hepatitis B Virus Infection among Pregnant Women Attending Antenatal Clinics in Vientiane, Laos, 2008-2014

The Lao People's Democratic Republic (PDR) is still considered a highly endemic country for hepatitis B, mainly due to perinatal transmission of hepatitis B virus (HBV), despite efforts made since 2004 for universal immunization of newborns. The prevalence of HBV surface antigen (HBsAg) carriage in pregnant women is a relevant marker for the risk of mother-to-child HBV transmission. This study aimed to assess the changes in prevalence of HBV infection among pregnant women attending the Mahosot Prenatal Clinic (Vientiane Capital). Methods. A retrospective study was performed in the Mahosot Hospital Laboratory to collect and analyze all the results of HBsAg testing in pregnant women from 2008 to 2014. Results. Of a total of 13,238 tested women of mean age of 26 years, 720 women (5,44% [95 CI: 5.1–5.8%]) were found HBsAg positive, the annual prevalence ranging from 4.6% to 6.2%. A slight but steady and significant decrease in prevalence over the 7 years of the study could be documented. Conclusion. Although below the 8% hyperendemic threshold, the HBsAg prevalence observed in pregnant women in Vientiane reflects a high risk of HBV perinatal transmission and call for a widespread infant immunization with an HBV vaccine birth dose.

Seroprevalence of hepatitis B surface antigen in pregnant women attending antenatal clinic in Honiara Solomon Islands, 2015

AIM

To determine the seroprevalence of hepatitis B surface antigen (HBsAg) among pregnant women attending antenatal clinic in Honiara, Solomon Islands.

METHODS

This descriptive cross-sectional study was carried out in seven area health centers in Honiara. From March to June 2015, identification of eligible pregnant women in each site was conducted using systematic random sampling technique. A total of 243 pregnant women who gave written informed consent were enrolled. Standardized tool was used to record demographics, obstetric history and serology results. HBsAg and hepatitis B e antigen (HBeAg) were tested using point-of-care rapid diagnostic test. All HBsAg positive samples were verified using enzyme-linked immunosorbent assay.

RESULTS

The mean age of participants was 26 ± 6 years. The overall hepatitis HBsAg prevalence was 13.8% with higher rate (22%) reported in women between 30-34 years of age. Majority of HBsAg positive participants were Melanesians (29 out for 33). None of the pregnant women in the 15-19 years and ≥ 40 years tested positive for HBsAg. There was no statistically significant difference in HBsAg prevalence by age, ethnicity, education and residential location. The overall HBeAg seroprevalence was 36.7%. Women between 20-24 years of age had the highest rate of 54.5%. Low level of knowledge about hepatitis B vaccination was reputed. Overall, 54.6% of participants were not aware of their hepatitis B vaccination status and only 65.2% of mothers reported their child had been vaccinated.

CONCLUSION

Hepatitis B is a disease of public health importance in Solomon Islands and emphasize the need for integrated preventative interventions for its control.

Characteristics of Pregnant Women With Hepatitis B Virus Infection in 5 US Public Health Jurisdictions, 2008-2012

OBJECTIVE

We estimated the prevalence of hepatitis B surface antigen (HBsAg), a serologic marker of active hepatitis B virus (HBV) infection, among pregnant women, and estimated the proportion HBsAg-positive pregnant women who had received additional recommended testing.

METHODS

From 2008 through 2012, Perinatal Hepatitis B Prevention Programs (PHBPPs) in Florida, Michigan, Minnesota, New York City, and Texas prospectively collected data on demographic characteristics of HBsAg-positive pregnant women. We estimated the prevalence of HBsAg positivity among pregnant women by demographic characteristics using natality data. PHBPPs (excluding Texas) collected additional recommended testing (for hepatitis B e antigen [HBeAg] and/or HBV deoxyribonucleic acid [DNA]) among HBsAg-positive pregnant women to measure levels of viremia.

RESULTS

During the study period, 15,205 HBsAg-positive women were case-managed. The median age of HBsAg-positive women was 29 years; prenatal HBsAg screening was at a median of 27 weeks pre-delivery. Of 15,205 HBsAg-positive women, 11,293 (74.3%) were foreign-born. In four PHBPPs with 14,098 pregnancies among 12,214 HBsAg-positive women, HBeAg and/or HBV DNA testing was documented for 2,794 (19.8%) pregnancies. The estimated prevalence of HBsAg positivity among pregnant women was 0.38% (17,023 of 4,468,773). HBsAg prevalence was highest among foreign-born women from most regions in Asia (2.0% to 8.7%; with the exception of South Asia, 0.4%) and Africa (3.4%).

CONCLUSION

One-fifth of HBsAg-positive pregnant women had documentation for HBeAg and/or HBV DNA, and about one-third reported receiving care for HBV infection during a case-managed pregnancy. Greater emphasis is needed on prenatal evaluation for HBV liver disease care and treatment among pregnant women with HBV infection.

Viral hepatitis vaccination during pregnancy

Viral hepatitis is a serious global public health problem. It is also a common cause of jaundice and gestational complications in pregnant women. Moreover, infected mothers can transmit the virus to their fetus or neonate, which may increase disease burden and decrease quality of life. To date, commercial vaccines have been developed for hepatitis A, B, and E and are available to the general population. The Advisory Committee on Immunization Practices currently accepts emergency vaccination against hepatitis A and B during pregnancy due to benefits that overweight the potential risks. While there are limited data from trials with limited numbers of samples that suggest the efficacy or safety of hepatitis B and E vaccines in pregnant women, additional data are necessary to provide evidence of vaccination during pregnancy.

Management of mother-to-child transmission of hepatitis B virus: Propositions and challenges

Chronic hepatitis B virus (HBV) infection due to mother-to-child transmission (MTCT) during perinatal period remains an important global health problem. Despite standard passive-active immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine in neonates, up to 9% of newborns still acquire HBV infection, especially these from hepatitis B e antigen (HBeAg) positive mothers. Management of HBV infection in pregnancy still need to draw careful attention because of some controversial aspects, including the failure of passive-active immunoprophylaxis in a fraction of newborns, the effect and necessity of periodical hepatitis B immunoglobulin (HBIG) injection to the mothers, the safety of antiviral prophylaxis with nucleoside/nucleotide analogs, the benefit of different delivery ways, and the safety of breastfeeding. In this review, we highlight these unsettled issues of preventive strategies in perinatal period, and we further aim to provide an optimal approach to the management of preventing MTCT of HBV infection.

Outcomes of infants born to women infected with hepatitis B

BACKGROUND AND OBJECTIVES

Perinatal exposure is an important mode of hepatitis B virus (HBV) transmission, resulting in chronic disease in ∼ 90% of infected infants. Immunoprophylaxis recommended for infants born to hepatitis B surface antigen-positive mothers reduces up to 95% of perinatal HBV infections. We sought to identify factors associated with perinatal HBV transmission.

METHODS

We analyzed prospectively collected data from 5 of 64 US-funded Perinatal Hepatitis B Prevention Programs during 2007-2013. We examined effects of maternal demographic and laboratory results, infant gestational age and birth weight, and immunoprophylactic management on perinatal HBV infection.

RESULTS

Data from 17,951 mother-infant pairs were analyzed. Among 9252 (51.5%) infants for whom hepatitis B surface antigen testing results were available, 100 (1.1%) acquired perinatal HBV infection. Both hepatitis B (HepB) vaccine and hepatitis B immune globulin were administered within 12 hours of birth for 10,760 (94.9%) of 11,335 infants with information. Perinatal HBV infection was associated with younger maternal age (P = .01), Asian/Pacific Islander race (P < .01), maternal hepatitis B e-antigen positivity (P < .01), maternal antibody to hepatitis B e-antigen negativity (P < .01), maternal viral load ≥ 2000 IU/mL (P = .04), and infant receipt of <3 HepB vaccine doses (P = .01). Four infants born to 429 mothers with viral load testing were infected; all 4 were born to mothers with viral loads in the ninth or tenth decile.

CONCLUSIONS

Perinatal HBV infection occurred among 1% of infants, most of whom received recommended immunoprophylaxis. Infants at greatest risk of infection were those born to women who were younger, hepatitis B e-antigen positive, or who had a high viral load or those infants who received <3 HepB vaccine doses.

Prevention of perinatal hepatitis B transmission in Haimen City, China: Results of a community public health initiative

In regions where hepatitis B virus (HBV) is endemic, perinatal transmission is common. Infected newborns have a 90% chance of developing chronic HBV infection, and 1 in 4 will die prematurely from HBV-related liver disease. In 2010, the Hepatitis B Foundation and the Haimen City CDC launched the Gateway to Care campaign in Haimen City, China to improve awareness, prevention, and control of HBV infection citywide. The campaign included efforts to prevent perinatal HBV transmission by screening all pregnant women for hepatitis B surface antigen (HBsAg), following those who tested positive, and administering immunoprophylaxis to their newborns at birth. Of 5407 pregnant women screened, 185 were confirmed HBsAg-positive and followed until delivery. At age one, 175 babies were available for follow up testing. Of those, 137 tested negative for HBsAg and positive for antibodies to HBsAg, indicating protection. An additional 34 HBsAg-negative babies also tested negative for antibodies to HBsAg or had indeterminate test results, were considered to have had inadequate immune responses to the vaccine, and were given a booster dose. A higher prevalence of nonresponse to HBV vaccine was observed among babies born to hepatitis B e antigen (HBeAg)-positive mothers and mothers with high HBV DNA titers. The remaining 4 babies tested positive for HBsAg and negative for antibodies, indicative of active HBV infection. The mothers of all 4 had viral loads ≥8×10(6) copies/ml in the third trimester. Although inadequate response or nonresponse to HBV vaccine was more common among babies born to HBeAg-positive and/or high viral load mothers, these risk factors did not completely predict nonresponsiveness. All babies born to HBV-infected mothers should be tested upon completion of the vaccine series to ascertain adequate protection. Some babies of HBeAg-positive mothers with high viral load may still become HBV infected despite timely immunoprophylaxis with HBV vaccine and HBIG.

Lamivudine treatment and outcome in pregnant women with high hepatitis B viral loads

Perinatal transmission is the most common mode of hepatitis B virus (HBV) transmission and is a leading cause of chronic infection worldwide. Maternal treatment with lamivudine (LAM) can result in a rapid and significant reduction in HBV viral load (VL) and, thus, mitigate the risk of mother-to-child transmission (MTCT). The aim of this study was to retrospectively evaluate the safety of LAM treatment administered in the third trimester of pregnancy and determine the influence, if any, on infant outcome. The medical charts of all HBV surface antigen (HBsAg)-positive women eligible for treatment with LAM and who registered for antenatal care between 2007 and 2012 were retrospectively reviewed. During the 6-year period, 45 women met the criteria for LAM treatment. Thirty-six women (80 %) accepted treatment; the remaining women declined treatment (5), defaulted from care (3) or transferred to another maternity unit (1). The median duration of treatment was 11.4 weeks (range 5.3-17.4) and the median baseline VL was 1.4 × 10(8) IU/mL (range 1.8 × 10(7)-1.7 × 10(8)). The median VL at delivery was 2.3 × 10(5) IU/mL and 60 % of women achieved a VL reduction >2 log10 IU/mL before delivery. No cases of perinatal transmission occurred in the infants born to mothers who received treatment; however, one infant, born to a mother who defaulted from care, was HBV-infected at 8 months. The results suggest that LAM therapy in highly viraemic HBV-infected pregnant women could lower the rate of vertical transmission.

Prevention of Perinatal Hepatitis B Virus Transmission

Hepatitis B virus (HBV) infection, the most common form of chronic hepatitis worldwide, is a major public health problem affecting an estimated 360 million people globally. Mother-to-child transmission (MTCT) is responsible for more than one third of chronic HBV infections worldwide. An estimated 15%-40% of persons chronically infected develop HBV-related complications, such as cirrhosis and hepatic carcinoma, and 25% die from these complications. MTCT can occur during pregnancy or during delivery. Screening pregnant women for HBV infection, providing infant postexposure prophylaxis, and maternal treatment with antiviral medications are strategies for reducing MTCT transmission rates and the global burden of new chronic HBV infections. Administration of hepatitis B immune globulin (HBIG) and hepatitis B (HepB) vaccine within 24 hours of birth, followed by completion of the vaccine series, is 85%-95% efficacious for prevention of MTCT. Despite timely post-exposure prophylaxis, MTCT occurs in 5%-15% of infants. Hepatitis B surface antigen (HBsAg) positive, hepatitis e antigen (HBeAg) positive mothers with HBV DNA level ≥10(6) copies/mL (>200 000 IU/mL) are at greatest risk of transmitting HBV to their infants. Consensus recommendations and evidence-based guidelines for management of chronic HBV infection and screening of pregnant women have been developed. The safety and efficacy of antiviral drug use during pregnancy are areas of ongoing research. Substantial advances have been achieved globally in reducing MTCT, but MTCT remains an ongoing health problem. Attaining a better understanding of the mechanisms of MTCT, implementing existing policies on maternal screening and infant follow-up, and addressing research gaps are critical for further reductions in MTCT transmission.

Efficacy and safety of tenofovir disoproxil fumarate in pregnancy to prevent perinatal transmission of hepatitis B virus

BACKGROUND & AIMS

Perinatal transmission of hepatitis B virus still occurs despite immunoprophylaxis in approximately 9% of children from highly viraemic mothers. Antiviral therapy in this setting has been suggested, however with limited evidence to direct agent choice.

METHODS

We conducted a multi-centre, prospective, opt-in observational study of antiviral safety and efficacy in pregnant women with high viral load (>7 log IU/ml); lamivudine was used from 2007 to 2010 and tenofovir disoproxil fumarate (TDF) from late 2010. Outcomes of treated and untreated cohorts were compared.

RESULTS

120 women with 130 pregnancies used TDF (58), lamivudine (52 including four who switched due to TDF intolerance) and no therapy (20). 96% were HBeAg positive, with baseline viral load mean 7.8 log IU/ml (±0.72) and ALT median 25 U/L (18.75-33). Duration of antiviral theraphy before birth was mean 58 days (±19) TDF and 53 (±14) lamivudine. Viral load declined by 3.64 log IU/ml (±0.9) TDF and 2.81 log IU/ml (±1.33) lamivudine. Virologic failure (birth viral load >7 IU/ml) occurred in 3% and 18% respectively. Congenital abnormality rate and neonatal growth centiles were similar across cohorts. Perinatal transmission reduced significantly to 2% and 0% in TDF and lamivudine cohorts, compared with 20% in untreated.

CONCLUSIONS

TDF in this setting is safe, effective and more potent than lamivudine. Antiviral therapy did not adversely impact obstetric or infant parameters. More TDF intolerance occurred than expected. Perinatal transmission was significantly reduced in antiviral therapy cohorts.