Viral factors for HBV mother-to-child transmission

Evolution and diversity of the hepatitis B virus genome: Clinical implications

Hepatitis B virus (HBV) infection remains a significant global health burden. The genetic variation of HBV is complex. HBV can be divided into nine genotypes, which show significant differences in geographical distribution, clinical manifestations, transmission routes and treatment response. In recent years, substantial progress has been made through various research methods in understanding the development, pathogenesis, and antiviral treatment response of clinical disease associated with HBV genetic variants. This progress provides important theoretical support for a deeper understanding of the natural history of HBV infection, virus detection, drug treatment, vaccine development, mother-to-child transmission, and surveillance management. This review summarizes the mechanisms of HBV diversity, discusses methods used to detect viral diversity in current studies, and the impact of viral genome variation during infection on the development of clinical disease.

Immunoprophylaxis failure and vaccine response in infants born to mothers with chronic hepatitis B infection in Djibouti

BACKGROUND

In endemic areas, vertical transmission of hepatitis B virus (HBV) remains a major source of the global reservoir of infected people. Eliminating mother-to-child transmission (MTCT) of HBV is at the heart of World Health Organization's goal of reducing the incidence of HBV in children to less than 0.1% by 2030. Universal screening for hepatitis B during pregnancy and neonatal vaccination are the main preventive measures.

AIM

To evaluate the efficacy of HBV vaccination combined with one dose of immunoglobulin in children born to hepatitis B surface antigen (HBsAg)-positive mothers in Djibouti city.

METHODS

We conducted a study in a prospective cohort of HBsAg-positive pregnant women and their infants. The study ran from January 2021 to May 2022, and infants were followed up to 7 mo of age. HBV serological markers and viral load in pregnant women were measured using aVidas microparticle enzyme-linked immunosorbent assay (Biomérieux, Paris, France) and the automated Amplix platform (Biosynex, Strasbourg, France). All infants received hepatitis B immunoglobulin and were vaccinated against HBV at birth. These infants were closely monitored to assess their seroprotective response and for failure of immunoprophylaxis. Simple logistic regression was also used to identify risk factors associated with immunoprophylaxis failure and poor vaccine response. All statistical analyses were performed with version 4.0.1 of the R software.

RESULTS

Of the 50 pregnant women recruited, the median age was 31 years, ranging from 18 years to 41 years. The MTCT rate in this cohort was 4% (2/50) in HBsAg-positive women and 67% (2/3) in hepatitis B e antigen-positive women with a viral load > 200000 IU/mL. Of the 48 infants who did not fail immunoprophylaxis, 8 (16%) became poor responders (anti-HB < 100 mIU/mL) after HBV vaccination and hepatitis B immunoglobulin, while 40 (84%) infants achieved a good level of seroprotection (anti-HB > 100 mIU/mL). Factors associated with this failure of immunoprophylaxis were maternal HBV DNA levels (> 200000 IU/mL) and hepatitis B e antigen-positive status (odds ratio = 158, 95% confidence interval: 5.05-4958, P < 0.01). Birth weight < 2500 g was associated with a poor immune response to vaccination (odds ratio = 34, 95% confidence interval: 3.01-383.86, P < 0.01).

CONCLUSION

Despite a failure rate of immunoprophylaxis higher than the World Health Organization target, this study showed that the combination of immunoglobulin and HBV vaccine was effective in preventing MTCT of HBV. Therefore, further studies are needed to better understand the challenges associated with immunoprophylaxis failure in infants in Djibouti city.

Real-world implementation of a multilevel interventions program to prevent mother-to-child transmission of HBV in China

Reducing hepatitis B virus (HBV) mother-to-child transmission (MTCT) is a fundamental step toward the HBV elimination goal. The multicentred, multilevel SHIELD program aimed to use an intense intervention package to reduce HBV MTCT in China. This study was conducted in diverse health settings across China, encompassing 30,109 pregnant women from 178 hospitals, part of the interim analysis of stage II of the SHIELD program, and 8,642 pregnant women from 160 community-level health facilities in stage III of the SHIELD program. The study found that the overall MTCT rate was 0.23% (39 of 16,908; 95% confidence interval (CI): 0.16-0.32%) in stage II and 0.23% (12 of 5,290; 95% CI: 0.12-0.40%) in stage III. The MTCT rate was lower among participants who were compliant with the interventions (stage II: 0.16% (95% CI: 0.10-0.26%); stage III: 0.03% (95% CI: 0.00-0.19%)) than among those who were noncompliant (3.16% (95% CI: 1.94-4.85%); 1.91% (95% CI: 0.83-3.73%); P < 0.001). Our findings demonstrate that the comprehensive interventions among HBV-infected pregnant women were feasible and effective in dramatically reducing MTCT.

C2729T mutation associated with HBV mother-to-child transmission reduces HBV production via suppressing LHBs expression

Mother-to-child transmission (MTCT) is still the main route of hepatitis B virus (HBV) infection. However, the virological factors affecting HBV MTCT have not been fully elucidated. In this study, based on a prospective cohort of mother-infant pairs with positive maternal hepatitis B surface antigen (HBsAg), we found that the average nucleotide mutation rate of HBV preS1 promoter (SPI) region in the immunoprophylaxis success group was significantly higher than that in the immunoprophylaxis failure group. Among the nucleotide mutations of the HBV SPI region, the C2729T mutation had the highest frequency. Next, we found that the C2729T mutation promoted HBsAg release but reduced HBV production by suppressing the expression of large hepatitis B surface antigen (LHBs), and overexpressing LHBs could rescue this phenomenon. Based on the fact that the C2729T mutation could alter the binding site of hepatocyte nuclear factor 1 (HNF1) in the HBV SPI region, we uncovered that such an alteration could downregulate the transcriptional activity of SPI by attenuating the binding ability of HNF1 and HBV SPI region. This study suggests that HBV C2729T mutation may contribute to the immunoprophylaxis success of HBV MTCT by reducing HBV production, which supplements the virological factors affecting HBV MTCT.

Efficacy and Long-term Safety of Telbivudine Usage During Second or Third Trimester in Hepatitis B Surface Antigen Positive Mothers With High Viral Load: A 10-year Prospective Study

GOALS

The study is to evaluate the efficacy and long-term safety of telbivudine (LdT) usage for hepatitis B surface antigen (HBsAg) positive pregnant women with high viral load.

BACKGROUND

The efficacy and safety of LdT during pregnancy were not assessed from a long-term perspective.

STUDY

HBsAg-positive pregnant women were enrolled and grouped according to antiviral initiation time. Group A (n=100) and group B (n=100) were treated with LdT initiated in the second or third trimester. Group C (n=90) received no antiviral treatment. The efficacy and safety of LdT treatment were compared and infants were followed-up at 1, 5, and 10 years. Denver developmental screening test was conducted at 5 years.

RESULTS

Viral loads before delivery in LdT-treated groups were lower than that in group C and group A was lower than that in group B ( P <0.001). No infants in LdT-treated groups were infected whereas 8.8% (8/90) infants in group C had positive HBsAg (χ 2 =23.20, P <0.001). All LdT-treated mothers were well tolerated and no LdT-related adverse events in infants were reported. Part of the physical growth index of infants was higher than Chinese standard values (SV) and showed significant differences. In groups A and B, the developmental screening test qualified rate of 100% (48/48) and 97.96% (48/49) showed no significant difference compared with 92% in normal Chinese children (χ 2 =5.72, P =0.06).

CONCLUSIONS

Treatment initiated during the second trimester could strengthen the success of mother-to-child transmission blockage. LdT treatment during pregnancy is safe for both mothers and infants in the long term.

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

PROBLEM

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

METHOD OF STUDY

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

RESULTS

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

CONCLUSIONS

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

Folic acid supplementation in pregnant women with hepatitis B surface antigen improves infant hepatitis B surface antibody mediated by infant IL-4

Immunoprophylaxis has not completely eliminated hepatitis B virus (HBV) infection due to hyporesponsiveness to hepatitis B vaccine (HepB). We explored the impact of folic acid supplementation (FAS) in pregnant women with positive hepatitis B surface antigen (HBsAg) on their infant hepatitis B surface antibody (anti-HBs) and the mediation effect of infant interleukin-4 (IL-4). We recruited HBsAg-positive mothers and their neonates at baseline. Maternal FAS was obtained via a questionnaire, and neonatal anti-HBs and IL-4 were detected. Follow-up was performed at 11-13 months of age of infants, when anti-HBs and IL-4 were measured. We applied univariate and multivariate analyses. A mediation effect model was performed to explore the mediating role of IL-4. A total of 399 mother-neonate pairs were enrolled and 195 mother-infant pairs were eligible for this analysis. The infant anti-HBs geometric mean concentrations in the maternal FAS group were significnatly higher than those in the no-FAS group (383·8 mIU/ml, 95 % CI: 294·2 mIU/ml to 500·7 mIU/ml v. 217·0 mIU/ml, 95 % CI: 147·0 mIU/ml to 320·4 mIU/ml, z = -3·2, P = 0·001). Infants born to women who took folic acid (FA) within the first trimester were more likely to have high anti-HBs titres (adjusted β-value = 194·1, P = 0·003). The fold change in IL-4 from neonates to infants partially mediated the beneficial influence of maternal FAS on infant anti-HBs (24·7 % mediation effect) after adjusting for confounding factors. FAS during the first trimester to HBsAg-positive mothers could facilitate higher anti-HBs levels in infants aged 11-13 months partly by upregulating IL-4 in infants.

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

Background

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

Methods

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

Results

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

Conclusions

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-PRC-09000459.

Developmental consequences of children born from mothers with telbivudine treatment during late pregnancy: A prospective study with 3-year follow-up

We prospectively investigated the neurological development in infants born from mothers treated with telbivudine (LdT) in the third trimester for prevention of hepatitis B virus (HBV) mother-to-infant transmission. Mothers with high HBV load were assigned to either the LdT group (n = 81, 600 mg of LdT each day from gestational week 28 to delivery) or the Control group (n = 39, untreated). Their infants were followed for 36 months to assess physical and neurological developments with Gesell Developmental Schedule tools. At 12 months after birth, the mean scores in the LdT group for gross motor, fine motor, adaptive, linguistic, and personal social domains were similar to those in the Control group. At 36 months, infants in the LdT group had higher mean scores for gross motor than the Control group (98.42 ± 9.69 vs. 94.54 ± 7.48, P = 0.03). In the LdT group, the rates of normal development were higher for gross motor (96.30% vs. 82.05% P = 0.01) and lower for adaptive (74.07% vs. 92.31% P = 0.02). Multivariate regression analyses showed that exposure to LdT during pregnancy was independently associated with infant’s development in gross motor (OR 6.49, 95% CI 1.37–30.20, P = 0.02) and adaptive (OR 0.18, 95% CI 0.05–0.71, P = 0.01) at 36 months. These results suggest that prenatal LdT exposure might affect neurological development in long-term observation.

Abbreviations: LdT: telbivudine; HBV: hepatitis B virus; HBsAg: hepatitis B surface antigen; HBeAg: hepatitis Be antigen; HbsAb: hepatitis B surface antibody; ALT: alanine aminotransferase; NA: nucleoside/nucleotide analog; LAM: lamivudine; MTCT: mother-to-child transmission; GDS: Gesell Developmental Schedule; OR: odds ratio; CI: confidence interval; DQ: developmental quotient; RMB: renminbi; BMI: body mass Index; HBIG: hepatitis B immunoglobulin.

Breast-Feeding is Not a Risk Factor of Mother-to-Child Transmission of Hepatitis B Virus

Purpose

This study aims at researching the content of hepatitis B virus (HBV) DNA in the breast milk of the mothers carrying HBV and investigating the effects of different feeding methods on mother-to-child transmission (MTCT) of HBV.

Methods

All infants were voluntarily chosen by their mothers and divided into breast-feeding group and formula-feeding group, which were divided into three subgroups, respectively: HBV-DNA negative (HBV-) group, low viral load (LVL) group and high viral load (HVL) group.

Results

HBV load in colostrum and mature milk were both significantly lower than in serum (P < 0.001). The positive rate of HBV-DNA in colostrum was positively correlated with HBV load in serum, significantly higher than that of the HBV-Group in colostrum in the LVL Group (P < 0.05), and the HVL Group was significantly higher than the LVL Group (P < 0.001). The analysis of risk factors of HBV infection in infants showed that breast-feeding and HBsAg positive in colostrum did not increase the risks of HBV infection of infants (P > 0.05).

Conclusion

Breast-feeding is safe for infants with HBV-infected mothers who receive active immunization combined with passive immunization. As well, breast-feeding will neither increase the risks of HBV infection for infants nor weaken their immunity to HBV. However, breast-feeding shall be cautiously applied to pregnant women with high viral load.

Cesarean section in reducing mother-to-child HBV transmission: a meta-analysis

BACKGROUND

A meta-analysis (MA) of natural vs. cesarean births in HBV infected mothers was performed to assess which delivery methods could minimize the mother-to-child transmission (MTCT) of Hepatitis B virus (HBV).

METHODS

Electrical databases PubMed, Embase and Cochrane Library were searched for the English papers about the HBV MTCT up to 19 August 2019. STATA 11.0 software was used for all analysis. Odds ratio (OR) and 95% confidence interval (CI) were used to present the effect size for MTCT at birth and MTCT more than 6 months. Heterogeneity was evaluated using the chi-squared Q and I ² test to determine the use of random effects model or fixed effects model.

RESULTS

A total of 19 articles involving 11,144 HBV-positive pregnant women (5251 underwent natural delivery and 5893 received a cesarean section) were included in the study. The pooled OR for MTCT at birth was 0.42, 95% CI: 0.23-0.76 based on random effect model (I ² = 69.9%, p = .019). Meanwhile, in fixed effect model (I ² = 0.0%, p = .470), the pooled OR for MTCT more than 6 months was 0.62, 95% CI: 0.48-0.81. The results indicated that HBV infection in cesarean births significantly lower than that of vaginal delivery. Subgroup analysis of MTCT more than 6 months was clearly, and the results indicated that cesarean section significantly reduced the risk of MTCT (OR = 0.62, 95% CI: 0.48-0.81, p < .001).

CONCLUSIONS

Cesarean section can reduce the risk of HBV MTCT and should be employed as a preventive measure. Due to the limitations of this study, further multi-center, large-sample randomized controlled trials must be performed to confirm these findings.

Hepatitis B and D in the Pacific Islands of Kiribati

BACKGROUND

Historical reports indicate that hepatitis B and hepatitis D are highly endemic in the Pacific Island of Kiribati but current levels are unknown.

OBJECTIVES

To determine current prevalence of HBV and HDV in Kiribati, characterize the strains in both mono-infection and co-infection and assess individuals for antiviral therapy.

STUDY DESIGN

Sera obtained from 219 patients were screened for HBsAg, HBeAg, HBV DNA, anti-HD, and HDV RNA. 61 HBV isolates were sequenced for genotype, phylogenetic analysis and detection of pre-core and basal core promoter mutations. 82 HDV isolates were also sequenced.

RESULTS

55.7 % HBsAg positive samples had antibodies to HDV and 73.2 % had detectable HDV RNA, indicating that 40.8 % HBsAg-positive individuals had current HBV/HDV co-infection. There were 42 co-infected males and 40 females; the youngest individual was a 4 year-old boy. HBV isolates were genotype D4, and HDV strains formed a distinct Pacific clade of genotype 1. Undetectable HBV DNA loads were statistically more frequent in the co-infected sub-population (p < 0.0001). Basal core promoter and pre-core mutations were present in both mono and co-infection.

CONCLUSION

Kiribati has one of the highest HBV/HDV co-infection rates in the world. The epidemiology of co-infection in this population was unusual with males and females equally represented and the presence of co-infection in a 4 year old child suggesting neonatal or early horizontal transmission, which is extremely rare. Coinfection with HDV resulted in statistically significant suppression of HBV DNA levels. The HDV strain identified in Kiribati was unique to the Pacific Islands.

Hepatitis B-management of acute infection and active inflammation in pregnancy-a hepatologist's perspective

Women at childbearing age and pregnant ladies living in the areas of high or intermediate prevalence of hepatitis B virus (HBV) remain at risk of getting the infection and passing the infections to their offspring via mother-to-child transmission (MTCT) of HBV. HBV infection may affect the mothers by active hepatitis, very occasionally liver cirrhosis and rarely fulminant hepatitis and liver failure. The virus may be transmitted to the babies despite immunoprophylaxis in the setting of very high maternal viral load. Tenofovir disoproxil fumarate (TDF) has been shown to be efficacious to reduce MTCT of HBV, which contributes to the elimination of chronic HBV infection by 2030, the goal set by World Health Organization.

Placental infection of hepatitis B virus among Thai pregnant women: Clinical risk factors and its association with fetal infection

OBJECTIVES

To identify the risk factors of placental and fetal infections among HBsAg-positive women.

METHODS

A prospective cohort study involving HBsAg-positive pregnant women was conducted. Maternal risk factors, including serum HBeAg status, anti-HBcIgM, and HBV-DNA levels, were determined. Placental infection was identified by PCR and confirmed by DNA sequencing. Fetal infection was defined as a positive umbilical cord blood HBV-DNA at birth.

RESULTS

A total of 96 HBsAg-positive women were enrolled in the study. The prevalence of placental infection was high (44 of 96; 45.8%) among HBsAg-positive women. The major risk factors for placental infection were high maternal viral load and the presence of HBeAg. Fetal infection was detected in one quarter of HBsAg-positive women (25 of 95; 25.3%). The risk of fetal infection was strongly associated with placental infection (78.3%), high maternal viral load, and the presence of HBeAg. There was no significant difference in perinatal outcomes between the groups with and without placental infection. Data on rates of chronic HBV infection in infants after fetal infection were not available.

CONCLUSION

A significant association between maternal measures of viral replication and placental and fetal infection was demonstrated. These findings suggest that transplacental infection prior to birth may be a mechanism contributing to the higher rates of newborn prophylaxis failure in women with a high viral load.

Abnormal IL-10 levels were related to alanine aminotransferase abnormalities during postpartum in HBeAg positive women with chronic hepatitis B

Alanine transaminase (ALT) abnormalities are common in chronic hepatitis B (CHB) carriers during postpartum period. Disturbances in cytokines are considered to be associated with hepatitis Flares. There are limited data on cytokines changes in HBeAg positive patients with ALT abnormalities.This is an observational study. Pregnant patients with hepatitis B e-antigen (HBeAg) positive were enrolled from January 2014 to September 2018. Patients were assigned into three groups based on ALT levels in postpartum 6 to 8 weeks: ALT in normal range, ALT in 1 to 2-fold upper limits of normal (ULN) and ALT >2-fold ULN. Serum cytokines, ratios of regulatory T cells, and the concentration of cortisol were collected and compared among the three groups.Of the 135 mothers enrolled, 80.7% (109/135) completed the postpartum 6-week study. 13.8% (15/109) patients had postpartum ALT higher than 2ULN, 27.5% (30/109) patients had ALT in 1 to 2ULN and 58.7% (64/109) patients had ALT in normal range. Compared to control group, patients with ALT >2ULN had a higher IL-10 level (P < .05). No differences of IL-10 levels were found in the comparison of other inter comparison among three groups. No differences were found in the levels of other collected serum cytokines, cortisol, and regulatory T cells among three groups. On multivariate analysis, abnormal IL-10 level was independent risk factor for postpartum ALT elevating >2ULN. At the same time, the incidence of postpartum ALT elevated >2ULN were higher in patients with abnormal elevation IL-10 level than in patients with normal IL-10 level (14/68 vs 1/41, P = .008).CHB patients with postpartum ALT abnormalities show higher IL-10 level and postpartum ALT abnormalities were mainly occurred in patients with abnormal IL-10 level. IL-10 may be an underlying predictor and treatment target of hepatitis B, and further studies are needed.

Effectiveness of tenofovir or telbivudine in preventing HBV vertical transmission for pregnancy

To evaluate the efficacy and safety of telbivudine (LdT) and tenofovir (TDF) for preventing hepatitis B virus (HBV) vertical transmission for HBV-positive pregnant women.Pregnant women (n = 145) from January 2013 to June 2017 were enrolled when they met inclusion criteria, which included HBV DNA ≥1.0 × 10 copies/mL and increased alanine aminotransferase (ALT) levels. Groups A (n = 58) and B (n = 51) were treated with LdT and TDF, respectively. Group C (n = 36) received no antiviral treatment. All infants were vaccinated with hepatitis B immunoglobulin and HBV vaccine. Vertical transmission of HBV was indicated by the presence of hepatitis B surface antigen (HBsAg) in infants 6 months and 12 months after birth.There is no difference of clinical characteristics of patients among the 3 groups. Serum HBV DNA levels of the 3 groups were similar at baseline (Group A vs. Group B vs. Group C, 7.88 ± 0.65 vs. 7.91 ± 0.75 vs. 7.69 ± 0.53 P = .25). In addition, the after anti-HBV treatment in Groups A and B were significantly decreased. Also, the serum HBV DNA levels in both Groups A and B were lower than that of Group C (P < .01, both). The HBV infection rate in Group A treated with LdT was not different from Group B treated with TDF. The dynamic changes of serum ALT level were similar. ALT levels were similar among the 3 Groups (P = .171), while there is statistically significant difference between A and C, and between B and C before delivery (P < .01). For the infants, there were no significant differences among body weight, height, head circumference, or Apgar score. However, the HBsAg positivity rates of infants in Groups A, B, C at postpartum 24 weeks and 48 weeks was 0%, 0%, and 11.1%, respectively (P < .001).Administration of LdT or TDF to HBV-infected mothers are effective and safe to block mother-to-infant HBV transmission.

Real-world study of tenofovir disoproxil fumarate to prevent hepatitis B transmission in mothers with high viral load

BACKGROUND

Data on tenofovir disoproxil fumarate (TDF) therapy for preventing vertical transmission of hepatitis B virus (HBV) in the real-world setting are limited.

AIM

To investigate TDF for preventing vertical transmission of HBV in real-world practice.

METHODS

Hepatitis B e-antigen (HBeAg)-positive mothers with HBV-DNA >6 log₁₀ IU/mL to receive TDF between gestational weeks 24-33 and delivery were prospectively enrolled and followed until post-partum week 28. All infants received immunoprophylaxis. Primary endpoints were safety of TDF use and mother-to-child transmission rates. Secondary outcomes were maternal HBV-DNA level suppression (<200 000 IU/mL) at delivery and HBeAg and hepatitis B surface antigen (HBsAg) serologic changes during the study.

RESULTS

Among 147 mothers enrolled, 143 started TDF and 143/144 infants completed the study. At delivery, 93.7% (134/143) of the mothers achieved HBV-DNA<200 000 IU/L. On-treatment, alanine aminotransferase (ALT) flares were observed in 8.4% (12/143) of mothers. After TDF cessation, ALT increased in 7.7% (11/143) of the mothers and 2.8% (4/143) achieved HBeAg negativity, but none had HBsAg loss. At birth, HBsAg was detected in 13.9% (20/144) of newborns and none at post-partum week 28. Vertical transmission rates among infants were 0.7% (1/144, intention-to-treat) and 0% (per-protocol). No infants had birth defects. No serious adverse effects were reported in either mothers or infants. Breastfeeding did not increase the HBV infection rate among infants although mothers had viral rebound after TDF cessation.

CONCLUSIONS

TDF for highly viraemic mothers was well tolerated and reduced vertical transmission of HBV in a real-world setting. There were no safety concerns during the postpartum 28-week follow-up. Registry number: Chinese Clinical Trial Registration No. ChiCTR-OIC-17010869.

Preventing vertical virus infections: the role of serologic screening of pregnant women

Several virus infections affect the pregnancy itself as well as the foetal development (rubella, PVB19, VZV, HSV, HCMV, HBV, HIV). Prevention can be established by vaccination or an assessment of the immunity status as well as by chemotherapy. The following review provides an update to current aspects focusing on the role of serologic screening.

Elimination of Vertical Transmission of Hepatitis B in Africa: A Review of Available Tools and New Opportunities

PURPOSE

This review article focuses on preventing vertical transmission of hepatitis B virus (HBV) among pregnant women living in sub-Saharan Africa (SSA), where disease is endemic and the estimated maternal HBV seroprevalence is >8%. Available interventions that have been studied in low- and middle-income countries are compared in terms of efficacy and effectiveness in clinical practice. Global disease-elimination targets, barriers to HBV-prevention efforts, and critical research gaps are discussed.

METHODS

A PubMed literature search in February 2018 identified relevant studies of interventions to reduce or prevent the transmission of HBV during pregnancy or in the peripartum period. Studies that focused on interventions that are currently available or could be made available in SSA were included. Trials conducted in SSA and other low-income countries were prioritized, although studies of interventions in middle- and high-income countries were included.

FINDINGS

Among 127 studies and reports included in the review, 60 included data from SSA. The most cost-effective intervention to reduce HBV infection rates in SSA is timely birth-dose vaccination followed by completion of the 3-dose infant-vaccination series. The identification and treatment of pregnant women with elevated HBV viral load to further reduce the risk for vertical transmission in SSA show promise, but efficacy and tolerability trials in Africa are lacking.

IMPLICATIONS

Scale-up of currently available tools is required to reach HBV disease-elimination goals in SSA. Many countries in SSA are in the process of rolling out national birth-dose vaccination campaigns; this roll out provides an opportunity to evaluate and improve processes in order to expand coverage. Early antenatal care, promotion of facility deliveries, and increased awareness of HBV prevention are also key components of prevention success. Future studies in SSA should identity an HBV-prevention package that is effective, well tolerated, and feasible and can be administered in the antenatal clinic and tailored to vertical-transmission risk.