Cesarean section reduces perinatal transmission of hepatitis B virus infection from hepatitis B surface antigen-positive women to their infants

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

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

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

OBJECTIVE

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

DESIGN

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

RESULTS

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

CONCLUSIONS

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

Safety of entecavir antiviral therapyduring an accidental pregnancy in patients with chronic hepatitis B

The present study aimed to investigate the effects of accidental pregnancy CHB patients' reproductive age on their offspring during entecavir (ETV) antiviral therapy. A total of 112 couples were retrospectively enrolled, and they were divided into an observational and control group. A total of 53 couples who had accidental pregnancies while receiving long-term ETV antiviral medication were recruited for the observational group. The control group consisted of 59 couples who became pregnant accidentally while receiving long-term tenofovir disoproxil fumarate (TDF) antiviral treatment. All mothers persisted in their pregnancies in the observational group, and ETV was promptly replaced with TDF. Every mother remained pregnant and continued to use TDF in the control group. The maternal and baby safety profiles, including the prevalence of congenital disabilities, were comparable across the observational and control groups at delivery. In addition, no unusual indications or symptoms of the newborns were noted during the follow-up intervals of 28, 48, and 96 weeks postpartum. Initiating ETV or TDF in early and middle pregnancy seems safe for mothers and infants. Important data from the present study support using ETV in early-mid gestational accidental pregnancies and the prompt substitution of TDF antiviral medication for ETV.

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

BACKGROUND

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

METHODS AND DATA SELECTION

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

RESULTS

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

CONCLUSIONS

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

Management Algorithm for Prevention of Mother-to-child Transmission of Hepatitis B Virus (2022)

The World Health Organization (WHO) has set the goal of eliminating hepatitis as a threat to public health by 2030. Blocking mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is not only the key to eliminating viral hepatitis, but also a hot issue in the field of hepatitis B prevention and treatment. To standardize the clinical management of preventing MTCT of HBV and achieve zero HBV infection among infants, the Chinese Foundation for Hepatitis Prevention and Control organized experts to compile a management algorithm for prevention of MTCT of HBV based on the latest research progress and guidelines, including 10 steps of pregnancy management and postpartum follow-up, among which screening, antiviral treatment, and infant immunization are its core components.

Maternal and neonatal viromes indicate the risk of offspring's gastrointestinal tract exposure to pathogenic viruses of vaginal origin during delivery

A cumulative effect of enterovirus and gluten intake on the risk of celiac disease autoimmunity in infants highlights the significance of viral exposure in early life on the health of children. However, pathogenic viruses may be transmitted to the offspring in an earlier period, raising the possibility that women whose vaginas are inhabited by such viruses may have had their babies infected as early as the time of delivery. A high-resolution intergenerational virome atlas was obtained by metagenomic sequencing and virome analysis on 486 samples from six body sites of 99 mother-neonate pairs. We found that neonates had less diverse oral and enteric viruses than mothers. Vaginally delivered newborns seconds after birth had a more similar oral virome and more viruses of vaginal origin than cesarean-section (C-section) newborns (56.9% vs. 5.8%). Such viruses include both Lactobacillus phage and potentially pathogenic viruses, such as herpesvirus, vaccinia virus, and hepacivirus, illustrating a relatively high variety of the pioneer viral taxa at the time of delivery and a delivery-dependent mother-to-neonate transmission along the vaginal-oral-intestinal route. Neonates are exposed to vaginal viruses as they pass through the reproductive tract, and viruses of vaginal origin may threaten their health. These findings challenge the conventional notion that vaginal delivery is definitely better than cesarean delivery from the perspective of microbial transmission. Screening for vaginal virome before delivery is a worthwhile step to advocate in normal labor to eliminate the risk of intergenerational transmission of pathogenic viruses to offspring.

Impact of hepatitis B virus infection on maternal and infant outcomes of women with gestational diabetes mellitus: A three-year retrospective study

AIMS

To explore the impact of HBV infection on maternal and infant outcomes of GDM women.

METHODS

We retrospectively identified 8126 women with GDM in China from July 2017 to June 2020, and divided them into GDM with HBV infection group (n = 483) and GDM with non-HBV infection group (n = 7643). Two sample t-test and Chi-square test were used to compare differences between groups. Logistic regression models were used to explore the association between HBV infection and maternal and infant outcomes.

RESULTS

Placental abruption (PA), (2.3% vs. 1.0%, P = 0.008), placenta previa (4.3% vs. 2.8% p = 0.044), intrahepatic cholestasis of pregnancy (ICP), (6.4% vs. 3.0%, P < 0.001), cesarean section (52.0% vs. 46.0%, P = 0.011), fetal chromosomal abnormalities (1.2% vs. 0.4%, P = 0.021), and neonatal hyperglycemia (1.9% vs. 3.6%, P = 0.047) were more likely to occur in GDM with HBV infection group. After adjusting for the covariates, HBV infection was found to be associated with ICP (aOR, 2.35; 95% CI: [1.58-3.50]), PA (aOR, 2.34; 95% CI: 1.22-4.47), and fetal chromosomal abnormalities (aOR, 2.88; 95% CI: 1.18-7.03).

CONCLUSIONS

HBV infection was associated with part of maternal and infant outcomes in the GDM population.

Treatment and prevention of viral hepatitis in pregnancy

Viral hepatitis in pregnancy may be caused by many types of viruses that cause systemic infection or target hepatocytes in their pathogenesis. Because viral hepatitis during pregnancy may represent acute or chronic infection or the reactivation of a prior infection, a high clinical suspicion, medical history review, and awareness of risk factors for the acquisition of infection are important management principles. The route of infection varies widely and ranges from fecal-oral transmission for the hepatitis A and E viruses to vertical transmission for hepatitis B, blood-borne transmission for hepatitis C, and sexual transmission for the herpes simplex virus. For this reason, the exposure details about travel, food preferences, drug use, and sexual contacts are important to elicit. Although routine prenatal screening is recommended for chronic viral hepatitis caused by hepatitis B and C, most other causes of viral hepatitis in pregnancy are detected in the setting of compatible signs and symptoms (fatigue, abdominal discomfort, jaundice, scleral icterus) or incidentally noted transaminitis on routine labs. Serologic testing is helpful for diagnosis with molecular testing as indicated to guide the management of hepatitis B and C. Preventive vaccines for hepatitis A and B with established safety of use in pregnancy are recommended for women who are at risk of acquisition. Postexposure prophylaxis for hepatitis A is a single dose of immunoglobulin and vaccination can be used if immunoglobulin G is not available. Antiviral therapy with tenofovir disoproxil fumarate is recommended as prophylaxis in pregnant women with active hepatitis B and an elevated viral load (>200,000 IU/mL) during the third trimester to prevent vertical transmission. The neonate exposed to hepatitis B at birth should receive immunoglobulin G and a monovalent birth dose vaccine within 12 hours, followed by completion of the 3-dosage vaccine series. The prevalence of hepatitis C in women of reproductive age has increased in the United States, and the role of antiviral therapy during pregnancy is of great interest. Cesarean delivery is not currently recommended for the sole purpose of reducing vertical transmission risk in pregnant women with viral hepatitis. Breastfeeding is recommended in women with hepatitis A, B, and C. New and promising prevention and treatment options for hepatitis B and C are under investigation. Investigators and regulatory authorities should ensure that these clinical trials for promising antivirals and vaccines are designed to include pregnant and lactating women.

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

Background

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

Aims

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

Methods

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

Results

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

Conclusions

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

Viral and bacterial factors of mother-to-child transmission of hepatitis B virus

Hepatitis B virus (HBV) infection is the tenth leading cause of death worldwide. Mother-to-child transmission of HBV occurring mainly at delivery remains one of the most common routes of infection in developing countries. One of the main challenges concerning HBV in Africa is to implement a prevention policy aiming at interrupting the cycle of pseudo-vertical transmission of this infection. The aim of this study was to assess the implication of certain bacterial and viral factors in mother-to-child transmission of HBV. This prospective study was conducted on 165 pregnant women carriers of HBV surface antigen (HBsAg) and their 169 newborns who attended care at the Gynecology Department of the University Hospital of Cocody. Serological, molecular, and bacteriological analyses were performed on blood samples and vaginal secretions. Mean viral load (VL) was 4.5 ± 1.3 log₁₀  IU/ml, while mean HBsAg titres were 3.5 ± 0.9 log₁₀  IU/ml. HBV DNA was found in vaginal secretions in 13.3% of mothers and in the blood of 10.3% of the newborns. Six bacterial species were identified in the vaginal discharge of pregnant women during labour before delivery. Staphylococcus aureus and Enterococcus faecalis were the most frequent species found in 23.0% and 13.9% of cases. Mothers positive for vaginal HBV DNA displayed higher plasma HBV DNA loads than negative mothers (6.2 ± 1.6 log₁₀  IU/ml vs. 4.3 ± 1.0 log₁₀  IU/ml, p < .0001). In conclusion, our study showed that presence of HBV DNA in vaginal secretions and the presence of S. aureus could play a role in mother-to-child transmission of HBV. HBV DNA detection in vaginal discharge represents a promising biomarker to identify newborns at risk of perinatal persistent infection.

Obstetric implications of maternal chronic hepatitis B virus infection

Antenatal screening for hepatitis B surface antigen seropositivity is widely adopted to identify pregnant women with chronic hepatitis B virus (HBV) infection in order to target their newborn infants for combined passive-active neonatal immunization to prevent the maternal-to-child transmission of HBV. It is less certain whether the presence of chronic HBV infection in these largely asymptomatic women could impact their pregnancy outcome. There is now gathering information in the literature, though sometimes conflicting, on the obstetric implications of chronic HBV infection. The conflicting data is most probably related to confounding factors such as the immunological phase of chronic HBV infection, viral genotype and activity, presence of hepatic inflammation and other co-existing liver disorders such as non-alcoholic fatty liver disease, and coinfection with other virus such as hepatitis C virus and micro-organisms, which are usually not examined, but which could have made significant influence on the occurrence of many of the pregnancy complications and adverse fetal and neonatal outcome. For pregnancy complications, the evidence suggests association with increased gestational diabetes mellitus, preterm birth, intrahepatic cholestasis of pregnancy, caesarean delivery, and postpartum haemorrhage, probably increased placental abruption and prelabour rupture of the membranes, and no effect or a reduction in the hypertensive disorders of pregnancy, especially preeclampsia. For perinatal outcome, there may be increased miscarriage and fetal malformations, and increase in both low birthweight and large-for-gestational age/macrosomic infants, as well as increased intrauterine fetal demise/stillbirth and fetal distress. However, most studies have not elaborated on the mechanisms or explanations of many of the adverse outcomes. Taken together, maternal chronic HBV infection increases the risk of adverse obstetric outcome overall, but further prospective studies are warranted to elucidate the reasons and mechanisms of, and with a view to mitigate, these adverse obstetric outcomes.

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

BACKGROUND

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

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.

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

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

The safety of antiviral therapy and drug withdrawal for the prevention of mother-to-child transmission of HBV during pregnancy

The efficacy of prenatal antiviral therapy (AVT) for preventing the vertical transmission of hepatitis B virus (HBV) is well demonstrated. However, data are limited regarding the safety of postpartum cessation of AVT, which may induce alanine aminotransferase (ALT) elevation. We aimed to investigate the necessity of prolonging maternal AVT after delivery. Chronic hepatitis B mothers at the immune-tolerant phase with HBV DNA levels >6 log10  IU/mL were prospectively enrolled and received AVT during the third trimester until delivery. Patients were offered to discontinue AVT either at delivery or postpartum week (PPW) 6. In addition, mothers who deferred AVT during pregnancy served as the control group. All mothers were followed until PPW 52 for clinical and virological parameters of hepatitis flares. Among 118 mothers recruited, 91 received AVT with 53 (group A) and 24 (group B) discontinue their treatment at delivery and PPW 6, respectively. Twenty-seven mothers who deferred AVT during pregnancy were followed as the control (group C). A total of 104 of 118 mothers who completed the study, 50% (52/104) had postpartum-elevated ALT levels, which were mild and moderate except 6 of 104 (5.77%) of patients had levels ≥5 times the upper limit of normal; 70% (36/52) of the ALT flares occurred within 12 weeks after delivery. In subgroup analyses, the frequency of ALT elevation was similar among the groups A vs B vs C (50.9% [27/53] vs 58.3% [14/24] vs 40.7% [11/27], respectively; P  = .447), as well as the mean peak ALT level (108.4/74.1/126.7 U/L in groups A/B/C, respectively; P = .291). Although postpartum ALT flares were common for mothers with or without AVT during pregnancy, most cases of ALT elevation were mild to moderate. Our study observed that extending AVT to PPW 6 did not affect maternal outcomes and ATV should be discontinued at birth. Close monitoring is warranted as severe flares rarely occurred.

Post exposure prophylaxis coverage, vertical transmission and associated factors among hepatitis B exposed newborns delivered at Arsi zone health institutions, 2019

INTRODUCTION

One third of the world population has been exposed to hepatitis B virus and an estimated 257 million people are chronically infected. The main route of hepatitis B virus (HBV) infection is vertical transmission. Post exposure prophylaxis is recommended by world health organization to have free Hepatitis B infection by 2030.

OBJECTIVE

The main purpose of this research project was to assess Hepatitis B virus post exposure prophylaxis coverage, rate of vertical transmission and factors among exposed newborns delivered at Arsi zone health institution.

METHODS

A cross-sectional study was conducted in Arsi zone health institutions among hepatitis B virus exposed newborns delivered at Arsi zone health institutions from January 2018 to September 2019. Systematic sampling technique was used to select 422 exposed newborns into the study. A pre-tested structured questionnaire and checklist were used to collect relevant data. Data was entered and cleaned using epidata7 & analyzed using SPSS version 25 software package. Both bivariate and multivariate analyses was carried out to identify associations. Odds ratio with 95% CI and P-value <0.05 was considered statistically significant.

RESULTS

The study revealed that among 401 exposed newborns only 83(20.7%), have been administered post exposure prophylaxis. But vertical transmission of hepatitis B virus (HBV) was observed in 32.4% (27.9%-36.9%) exposed newborns. Antenatal (ANC) attendance (AOR = .40, 95%CI = .23-.69), Instrumental delivery (AOR = 4.18, 95%CI = 2.05-8.51) HIV coinfection (AOR = 9.7, 95%CI = 4.37-21.34), Post exposure Prophylaxis (AOR = .20, 95%CI = .08-.50) and Knowledge on HBV (AOR = .27, 95%CI = .14-.53) are significant predictors of HBV vertical transmission.

CONCLUSION

Magnitude of HBV post exposure prophylaxis coverage is very low while Rate of vertical transmission is high. Antenatal attendance, Instrumental delivery, Post exposure Prophylaxis and Knowledge on hepatitis B virus transmission are significant predictors of HBV vertical transmission.

Efficacy and safety of tenofovir alafenamide fumarate for preventing mother-to-child transmission of hepatitis B virus: a national cohort study

BACKGROUND

Data on tenofovir alafenamide fumarate (TAF) for preventing mother-to-child transmission of hepatitis B virus (HBV) are lacking.

AIMS

To investigate the efficacy and safety of TAF therapy for preventing hepatitis B mother-to-child transmission.

METHODS

Mothers with chronic HBV infection, positive for hepatitis B e-antigen and with HBV DNA >200 000 IU/mL received TAF for preventing mother-to-child transmission were enrolled retrospectively from multiple centres with data collection on mother-infant dyads up to postpartum week 24-28. Primary measurements were the mother-to-child transmission rate and infants' malformation rate. Secondary assessments included maternal HBV DNA reduction at delivery, and maternal or infant adverse events during follow up.

RESULTS

Among 71 mothers enrolled, the mean (±SD) age was 30.3 (±2.2) years. TAF was initiated during the second or third trimester and continued to delivery with a mean (±SD) duration of 12.8 (±4.0) weeks. At delivery, 85.9% (61/71) of the mothers achieved HBV DNA <200 000 IU/L. Seventy-three infants (two sets of twins) were born from mothers treated with TAF and none had congenital defects or malformations. All infants received HBV immunoglobulin and vaccine at birth with additional HBV vaccinations at one and six months. At age 24-28 weeks, all infants had negative hepatitis B surface antigen and undetectable levels of HBV DNA (<100 IU/mL). Body weight, height, and head circumferences were comparable to national standards for physical development. No severe adverse effects were reported in either mothers or infants.

CONCLUSIONS

TAF for highly viraemic mothers effectively prevented mother-to-child transmission of hepatitis B. There were no safety concerns for either mothers or infants with 24-28 weeks of follow up.

The role of caesarean section and nonbreastfeeding in preventing mother-to-child transmission of hepatitis B virus in HBsAg-and HBeAg-positive mothers: results from a prospective cohort study and a meta-analysis

The study aimed to assess whether caesarean section and nonbreastfeeding can prevent mother-to-child transmission (MTCT) in HBsAg- and HBeAg-positive mothers via a cohort study and a meta-analysis. (1) Pregnant women who were positive for HBsAg and HBeAg and did not receive antiviral treatment during pregnancy were recruited from the First Hospital of Jilin University, Maternal and Child Health Care Center of Jiangsu and Henan from August 2009 to June 2015. Infants received active and passive immunity. (2) In addition, a systematic literature search was performed in the PubMed, Embase, Cochrane, China National Knowledge Infrastructure and Wanfang Chinese databases. The retrieval strategy was [("HBV" or "hepatitis b" or "hepatitis b virus") and ("mother-to-infant transmission" or "vertical transmission")]. Studies were screened, and data were extracted. The fixed-effect model was used to analyse the studies. A total of 852 mothers and 857 newborns were enrolled. At the age of 7 months, 41 infants (4.78%) were positive for HBsAg. Multivariate analysis showed that mothers with higher HBV DNA levels (>10⁸  IU/mL; RR = 3.03, 95% CI: 1.41-6.52) were associated with an increased risk of infection. Although there was no statistical significance, caesarean section (RR = 0.61) and nonbreastfeeding (RR = 0.88) showed a tendency to reduce the risk of infection. (2) A total of 5726 studies were identified. Together with our study, 13 were included in the analysis of delivery mode, and 12 were included in the analysis of feeding mode. The risk of infection in the caesarean section group was lower than that in the vaginal delivery group (RR = 0.58, 95% CI: 0.46-0.74). In the analysis of feeding mode, the risk in the nonbreastfeeding group was significantly lower (RR = 0.74, 95% CI: 0.56-0.98). In conclusion, caesarean section and nonbreastfeeding reduced the risk of MTCT in infants of HBsAg- and HBeAg-positive mothers who did not receive antiviral therapy during pregnancy.

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.

Accuracy of HBeAg to identify pregnant women at risk of transmitting hepatitis B virus to their neonates: a systematic review and meta-analysis

BACKGROUND

Prevention of mother-to-child transmission (MTCT) of hepatitis B virus (HBV) involves neonatal immunoprophylaxis, with a birth dose of hepatitis B vaccine and immune globulin, and provision of peripartum antiviral prophylaxis in highly viraemic women. However, access to assays to quantify HBV DNA levels remains inadequate in resource-poor settings. This study was commissioned by WHO and aimed to identify the HBV DNA threshold for MTCT, to assess the sensitivity and specificity of hepatitis B e antigen (HBeAg) testing to identify pregnant women with HBV DNA levels above this threshold, and to predict MTCT of HBV infection on the basis of HBeAg testing.

METHODS

For this systematic review and meta-analysis, we searched the PubMed, EMBASE, Scopus, CENTRAL, CNKI, and Wanfang databases for studies of pregnant women with chronic HBV infection without concurrent antiviral therapy, published between Jan 1, 2000, and April 3, 2019. Studies were eligible for inclusion if MTCT in mother-child pairs could be stratified by different levels of maternal HBV DNA during pregnancy, if maternal HBeAg status could be stratified by HBV DNA level, and if the MTCT status of infants could be stratified by maternal HBeAg status during pregnancy. Studies that selected pregnant women on the basis of HBeAg serostatus or HBV DNA levels were excluded. Aggregate data were extracted from eligible studies by use of a pre-piloted form; study authors were contacted to clarify any uncertainties about potential duplication or if crucial information was missing. To pool sensitivities and specificities of maternal HBeAg to identify highly viraemic women and to predict MTCT events, we used the DerSimonian-Laird bivariate random effects model. This study is registered with PROSPERO, CRD42019138227.

FINDINGS

Of 9007 articles identified, 67 articles (comprising 66 studies) met the inclusion criteria. The risk of MTCT despite infant immunoprophylaxis was negligible (0·04%, 95% CI 0·00-0·25) below a maternal HBV DNA level of 5·30 log₁₀ IU/mL (200 000 IU/mL) and increased above this threshold. The pooled sensitivity of HBeAg testing to identify HBV DNA levels of 5·30 log₁₀ IU/mL or greater in pregnant women was 88·2% (83·9-91·5) and pooled specificity was 92·6% (90·0-94·5). The pooled sensitivity of HBeAg testing in predicting MTCT of HBV infection despite infant immunoprophylaxis was 99·5% (95% CI 91·7-100) and pooled specificity was 62·2% (55·2-68·7).

INTERPRETATION

Maternal HBV DNA of 5·30 log₁₀ IU/mL or greater appears to be the optimal threshold for MTCT of HBV infection despite infant immunoprophylaxis. HBeAg is accurate to identify women with HBV DNA levels above this threshold and has high sensitivity to predict cases of immunoprophylaxis failure. In areas where HBV DNA assays are unavailable, HBeAg can be used as an alternative to assess eligibility for antiviral prophylaxis.

FUNDING

World Health Organization.

Effects of intrauterine exposure to maternal-derived HBeAg on T cell immunity in cord blood

Immature immune system and immune tolerance induced by exposure to HBeAg in utero and/or shortly after infection in newborns were reportedly the causes of chronic HBV infection. To investigate the effect of maternal-derived HBeAg on neonatal T cell immunity, we analysed and compared T cell phenotypes and functions among neonates born to HBsAg⁺ /HBeAg⁺ mothers (HBeAg⁺ neonates), HBsAg⁺ /HBeAg^- mothers (HBeAg^- neonates) and healthy control mothers (HC neonates), using flow cytometry. The results showed that neonatal T cell phenotypes were similar regardless of HBeAg exposure. Upon anti-CD3 and anti-CD28 stimulation in HBeAg⁺ neonates, CD4⁺ T cell production of IFN-γ (P < .05) was significantly enhanced, while CD8⁺ T cells secreted significantly more IL-2 compared with those in HBeAg^- and HC groups (P < .05). Moreover, similar levels of IFN-γ and IL-10 were observed in the culture supernatant after stimulation with rHBsAg, rHBcAg or rHBeAg among HBeAg⁺ , HBeAg^- and HC neonates, whereas HBeAg⁺ neonates produced more TNF-α than HBeAg^- neonates upon stimulation with rHBcAg. In conclusion, the results indicated that the HBsAg⁺ /HBeAg⁺ maternal environment did not influence the phenotypes of cord blood T cells but boosted neonatal non-specific Th1-type cytokine production.

Impact of the National Perinatal Hepatitis B Prevention Programme in the Republic of Korea: A retrospective registry-based cohort study

INTRODUCTION

Hepatitis B is a major preventable cause of morbidity and mortality from chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. We aimed to evaluate the performance and outcomes of the Korean Perinatal Hepatitis B Prevention Programme (PHBPP) and to investigate the impact of the current post-exposure immunoprophylaxis protocol.

METHODS

A retrospective cohort study was performed based on electronic data registry of infants born to hepatitis B virus (HBV)-infected mothers between July 2002 and 2013.

RESULTS

During the study period, 159,983 Korean infants were registered with the PHBPP, with an overall programme coverage of 92.8%. Despite receiving timely post-exposure immunoprophylaxis, 8.6% of infants born to mothers aged <25 years and hepatitis B e antigen (HBeAg)-positive, and 0.7% of infants born to mothers aged ≥25 years and HBeAg-negative were infected. An estimated 14,123 infants were directly protected from perinatal HBV transmission by the PHBPP during the 11.5-year period, at a cost of 1157 US dollars per case averted. The incidence of paediatric hepatocellular carcinoma declined dramatically during the period.

CONCLUSIONS

A substantial number of infants have been prevented from hepatitis B since the PHBPP was launched in the Republic of Korea. Continued efforts to promote the programme, an integrated approach to maximising its coverage, a risk-stratified strategy, and innovations in logistics could further reduce perinatal HBV transmission.

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.

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 - chronic carrier status and pregnancy outcomes: An obstetric perspective

Antenatal screening for hepatitis B surface antigen (HBsAg) only identifies women with hepatitis B virus (HBV) infection for neonatal immunoprophylaxis. It does not reflect the phase of chronic infection, viral genotype and activity, hepatic inflammation, or other co-existing liver disorders. Coinfection with other viruses and micro-organisms may also be present. These factors in various combinations can impact pregnancy outcomes, and they are probably responsible for the conflicting literature on this issue. Pregnancy complications may interact with maternal HBV infection and hepatitis flares, leading to serious and lethal complications. Hepatitis flares are common especially postpartum, and they are unpredictable and unpreventable with antiviral treatment. Evidence on the association between HBsAg seropositivity with gestational diabetes mellitus, preterm birth, increased foetal growth, and reduced pregnancy hypertensive disorders is stronger than other adverse pregnancy outcomes. Baseline assessment of liver function, and viral markers and activity, can delineate the truly high-risk pregnancies for close monitoring.

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.

Quantitative Hepatitis B Surface Antigen Predicts Hepatitis B Transmission in Infants Born to e Antigen-positive Mothers

GOALS

This study aimed to explore whether quantitative surface antigen [hepatitis B surface antigen (HBsAg)] can be used as a surrogate marker of hepatitis B virus (HBV) DNA to predict hepatitis B transmission before the first hepatitis vaccine dose in infants born to hepatitis B e antigen (HBeAg)-positive pregnant women.

BACKGROUND

Currently, HBV transmission persistently occurs worldwide, especially in infants born to e antigen (HBeAg)-positive highly viremic mothers. However, due to high cost, the extensive use of viral load testing to identify these high-risk mothers is limited.

MATERIALS AND METHODS

In total of 275 HBeAg-positive pregnant women paired with 280 infants were enrolled in this study. Quantitative HBsAg and HBV DNA levels were measured in the third trimester. Spearman rank correlation was used to assess the correlation between HBsAg levels and viral load, and multivariate logistic regression to identify factors related to HBV transmission in infants.

RESULTS

Among 280 infants included, 15 (5.4%) infants were infected with HBV. In this study, we observed that quantitative HBsAg was positively correlated with maternal viral load (r=0.70, P<0.001) and highly predicted HBV transmission in infants born to HBeAg-positive mothers with area under the curve of 0.76 (95% confidence interval, 0.71-0.81). The optimum threshold HBsAg levels above 4.6 log10 IU/mL to predict HBV transmission in infants had a sensitivity of 80.0%, specificity of 67.9%.

CONCLUSIONS

Quantitative HBsAg could be used as a surrogate marker of HBV DNA levels to predict hepatitis B transmission occurring before the injection of first-dose vaccine in infants born to e antigen-positive mothers.

Vaginal delivery and HBV mother to child transmission risk after immunoprophylaxis: A systematic review and a meta-analysis

OBJECTIVE

HBV mother to child transmission (MTCT) can be prevented by passive and active immunoprophylaxis. In this study, we aim to assess whether vaginal delivery is safe for HBV MTCT after immunoprophylaxis.

MATERIAL AND METHODS

PubMed and Web of Science were systematically searched. We compared the MTCT incidence of infants at 6 months or older between vaginal delivery and caesarean section. Serological HBV positive incidences for newborns at birth were also compared.

RESULTS

Eighteen studies with 11,446 mother-child pairs were included in the meta-analysis. The average incidence of serological HBV positive for newborns at birth was 7.2% in the cesarean section group, and 16.6% in the vaginal delivery group. The summary odds ratio (OR) was 0.499 (95% CI 0.364-0.684; Z = 4.33, P < 0.00001) between two groups. However, the average incidences of MTCT were 3.3% and 4.1% for the cesarean section group and the vaginal delivery group, respectively. The summary OR compared between two groups was 0.790 (95% CI 0.614 to 1.016; Z = 1.83, P = 0.067). The funnel plot, Begg's Test (z = -0.55, P = 0.583) and Egger's test (t = -0.29, P = 0.777) suggested there was no publication bias among the included studies. Sensitive analyze showed the ORs were 0.764 (95% CI 0.490 to 1.192; Z = 1.19, P = 0.236), and 0.386 (95% CI 0.132 to 1.125; Z = 1.74, P = 0.0081), respectively.

CONCLUSION

The vaginal delivery did not increase the HBV MTCT incidence after immunoprophylaxis at 6 months old or more. The existing evidence does not support the conclusion that caesarean section can prevent MTCT in HBsAg-positive mother after immunoprophylaxis. However, this conclusion should be cautious in the HBV mother with high viral load.

Epidemiological trends and virological traits of hepatitis B virus infection in pregnant women and neonates

In infants, hepatitis B virus (HBV) infections are mainly acquired by mother-to-child transmission (MTCT). Current tests for the presence of HBV markers at birth can neither confirm nor exclude MTCT. The aim of this study was to find an early diagnostic marker of HBV MTCT. From 2011 to 2016, we studied a total of 5999 pregnant women who gave birth at our hospital in Shenzhen City, China. HBsAg-positive mothers and their offspring (n=386 pairs) were tested at birth for HBV markers, and 207 infants were followed up at 7-12 months after birth. The HBsAg-seropositive rate of the pregnant women was 12.5%. Additionally, 28.0%, 36.0%, 98.5% and 6.6% of umbilical cord (UC) blood samples of neonates were found to be positive for HBsAg, HBeAg, anti-HBc and HBV-DNA, respectively, whereas for neonatal femoral venous (FV) blood, the percentages were 16.2%, 38.0%, 98.8% and 2.6%, respectively. Mothers with high HBV DNA loads and those who were HBeAg positive were the most likely to have HBV-positive offspring. Immunoprophylaxis failed in five infants: the difference in median HBV DNA titer between UC blood from infants with and without HBV MTCT was statistically significant, and there was no significant difference in HBV DNA titer between UC blood and in peripheral blood of infants with HBV MTCT. In conclusion, we found that HBeAg positivity and high HBV loads are strong risk factors for MTCT of HBV and that the HBV DNA titer in the UC is a good predictor for HBV MTCT.

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.

Incidence and Risk Factors of Intrauterine Transmission Among Pregnant Women With Chronic Hepatitis B Virus Infection

GOALS

To identify the potential risk factors of hepatitis B virus (HBV) intrauterine transmission and predict the incidence of HBV intrauterine transmission among hepatitis B surface antigen-positive pregnant women with diverse viral load.

BACKGROUND

The intrauterine transmission of HBV significantly contributes to the persistence of a high number of patients infected with HBV. However, its risk factors remain unclear.

MATERIALS AND METHODS

A prospective study was performed on hepatitis B surface antigen-positive pregnant women who delivered from June 2012 to December 2016 at Wuhan Medical Care Center for Women and Children, Wuhan, China.

RESULTS

In total, 1200 women paired with 1219 infants were enrolled. In total, 11 (0.9%) infants were identified with intrauterine transmission. We observed that all infants with intrauterine transmission were born to hepatitis B e antigen-positive mothers who had serum HBV DNA levels >7 log10 copies/mL. Our study suggested that the HBV DNA levels (for each log10 copies/mL increase, odds ratio=5.43; 95% confidence interval, 1.31-22.43; P=0.019) had independent effects on HBV intrauterine transmission in a multivariate logistic regression model. Moreover, cesarean section (odds ratio=0.18; 95% confidence interval, 0.04-0.74; P=0.018) was associated with a reduced risk of HBV intrauterine transmission. The predictive rates of intrauterine transmission were 0.06%, 0.50%, 2.81%, 8.89% in infants with maternal HBV DNA levels of 10, 10, 10, 10 copies/mL, respectively.

CONCLUSIONS

Our data confirmed that increasing maternal viral load has the ability to predict intrauterine HBV transmission. Vaginal delivery increased risk of HBV transmission in infants compared with cesarean section. Further studies are warranted to clarify the possible mechanism underlying these associations.

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.

Cesarean section reduces the risk of early mother-to-child transmission of hepatitis B virus

AIMS

To evaluate the effects of cesarean section (CS) on the prevention of mother-to-child transmission (MTCT) of hepatitis B virus (HBV) among hepatitis B surface antigen (HBsAg) positive pregnant women.

METHODS

A prospective cohort study was performed on HBsAg-positive pregnant women who delivered from June 2012 to March 2017 at Wuhan Medical Care Center for Women and Children in Wuhan, China. Logistic regression models were used to examine the associations between mode of delivery and the presence of HBV MTCT.

RESULTS

A total of 1384 women paired with 1407 infants were enrolled. Our study showed that the incidence of HBV MTCT was 1.0% (14/1407) in infants born to HBsAg-positive pregnant women. We observed that the infants born by CS had a smaller percentage of HBV infection than those born by vaginal delivery (VD) (0.5% vs 1.7%, P = 0.043). In the fully adjusted model, CS was significantly associated with a decreased risk of HBV MTCT (OR = 0.26; 95% CI: 0.07-0.95; P = 0.042).

CONCLUSION

Our data confirmed that CS has a protective effect on early MTCT of HBV. CS for HBeAg-positive mothers with high viral load could reduce risk of MTCT and may become a new preventive measure of HBV MTCT through research on its risk-benefit assessment.

Maternal viral load and hepatitis B virus mother-to-child transmission risk: A systematic review and meta-analysis

AIM

The aim of this study was to assess the relationship between maternal viral load and mother-to-child transmission (MTCT) risk in hepatitis B envelope antigen (HBeAg)-positive mothers.

METHODS

PubMed and Web of Science were systematically searched. We compared MTCT incidence between maternal hepatitis B virus (HBV)-DNA-positive and HBV-DNA-negative groups. We also examined the dose-response effect of this relationship.

RESULTS

Twenty-one studies with 10 142 mother-child pairs were included in the studies. The mean MTCT incidence was 13.1% in the maternal HBV-DNA-positive group, compared with 4.2% in the negative group. The summary MTCT odds ratio of maternal HBV-DNA positive compared with negative was 9.895 (95% confidence interval [CI], 5.333 to 18.359; Z = 7.27, P < 0.00001) by random-effects model. In maternal HBV-DNA <6 log10 copies/mL, 6-8 log10 copies/mL, and >8 log₁₀ copies/mL level stratifications, the pooled MTCT incidences were 2.754% (95% CI, 1.198-4.310%; Z = 3.47, P = 0.001), 9.932% (95% CI, 6.349-13.516%; Z = 5.43, P < 0.00001), and 14.445% (95% CI, 8.317-20.572%; Z = 4.62, P < 0.00001), respectively. A significant linear dose-response association was found between maternal viral load and MTCT risk, with the points estimate of increased MTCT risk 2.705 (95% CI, 1.808-4.047) at 6 log10 copies/mL compared with reference (3 log10 copies/mL), and 7.316 (95% CI, 3.268-16.378) at 9 log₁₀  copies/mL. A significant non-linear dose-response association was also found between maternal viral load and HBV MTCT risk (model χ²  = 23.43, P < 0.00001).

CONCLUSION

Our meta-analysis indicated that maternal viral load was an important risk factor for MTCT in HBeAg-positive mothers, and maternal viral load was dose-dependent with HBV MTCT incidence.

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.

An expert consensus for the management of chronic hepatitis B in Asian Americans

BACKGROUND

Hepatitis B virus (HBV) infection is common with major clinical consequences. In Asian Americans, the HBsAg carrier rate ranges from 2% to 16% which approximates the rates from their countries of origin. Similarly, HBV is the most important cause of cirrhosis, hepatocellular carcinoma (HCC) and liver related deaths in HBsAg positive Asians worldwide.

AIM

To generate recommendations for the management of Asian Americans infected with HBV.

METHODS

These guidelines are based on relevant data derived from medical reports on HBV from Asian countries as well as from studies in the HBsAg positive Asian Americans. The guidelines herein differ from other recommendations in the treatment of both HBeAg positive and negative chronic hepatitis B (CHB), in the approach to HCC surveillance, and in the management of HBV in pregnant women.

RESULTS

Asian American patients, HBeAg positive or negative, with HBV DNA levels >2000 IU/mL (>10⁴ copies/mL) and ALT values above normal are candidates for anti-viral therapy. HBeAg negative patients with HBV DNA >2000 IU/mL and normal ALT levels but who have either serum albumin <3.5 g/dL or platelet count <130 000 mm³ , basal core promoter (BCP) mutations, or who have first-degree relatives with HCC should be offered treatment. Patients with cirrhosis and detectable HBV DNA must receive life-long anti-viral therapy. Indications for treatment include pregnant women with high viraemia, coinfected patients, and those requiring immunosuppressive therapy. In HBsAg positive patients with risk factors, life-long surveillance for HCC with alpha-fetoprotein (AFP) testing and abdominal ultrasound examination at 6-month intervals is required. In CHB patients receiving HCC treatments, repeat imaging with contrast CT scan or MRI at 3-month intervals is strongly recommended. These guidelines have been assigned to a Class (reflecting benefit vs. risk) and a Level (assessing strength or certainty) of evidence.

CONCLUSIONS

Application of the recommendations made based on a review of the relevant literature and the opinion of a panel of Asian American physicians with expertise in HBV treatment will inform physicians and improve patient outcomes.

Tenofovir versus Placebo to Prevent Perinatal Transmission of Hepatitis B

BACKGROUND

Pregnant women with an elevated viral load of hepatitis B virus (HBV) have a risk of transmitting infection to their infants, despite the infants' receiving hepatitis B immune globulin.

METHODS

In this multicenter, double-blind clinical trial performed in Thailand, we randomly assigned hepatitis B e antigen (HBeAg)-positive pregnant women with an alanine aminotransferase level of 60 IU or less per liter to receive tenofovir disoproxil fumarate (TDF) or placebo from 28 weeks of gestation to 2 months post partum. Infants received hepatitis B immune globulin at birth and hepatitis B vaccine at birth and at 1, 2, 4, and 6 months. The primary end point was a hepatitis B surface antigen (HBsAg)-positive status in the infant, confirmed by the HBV DNA level at 6 months of age. We calculated that a sample of 328 women would provide the trial with 90% power to detect a difference of at least 9 percentage points in the transmission rate (expected rate, 3% in the TDF group vs. 12% in the placebo group).

RESULTS

From January 2013 to August 2015, we enrolled 331 women; 168 women were randomly assigned to the TDF group and 163 to the placebo group. At enrollment, the median gestational age was 28.3 weeks, and the median HBV DNA level was 8.0 log₁₀ IU per milliliter. Among 322 deliveries (97% of the participants), there were 319 singleton births, two twin pairs, and one stillborn infant. The median time from birth to administration of hepatitis B immune globulin was 1.3 hours, and the median time from birth to administration of hepatitis B vaccine was 1.2 hours. In the primary analysis, none of the 147 infants (0%; 95% confidence interval [CI], 0 to 2) in the TDF group were infected, as compared with 3 of 147 (2%; 95% CI, 0 to 6) in the placebo group (P=0.12). The rate of adverse events did not differ significantly between groups. The incidence of a maternal alanine aminotransferase level of more than 300 IU per liter after discontinuation of the trial regimen was 6% in the TDF group and 3% in the placebo group (P=0.29).

CONCLUSIONS

In a setting in which the rate of mother-to-child HBV transmission was low with the administration of hepatitis B immune globulin and hepatitis B vaccine in infants born to HBeAg-positive mothers, the additional maternal use of TDF did not result in a significantly lower rate of transmission. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT01745822 .).

Paediatric Virology and its interaction between basic science and clinical practice (Review)

The 3rd Workshop on Paediatric Virology, which took place on October 7th, 2017 in Athens, Greece, highlighted the role of breast feeding in the prevention of viral infections during the first years of life. Moreover, it focused on the long-term outcomes of respiratory syncytial virus and rhinovirus infections in prematurely born infants and emphasised the necessity for the development of relevant preventative strategies. Other topics that were covered included the vaccination policy in relation to the migration crisis, mother‑to‑child transmission of hepatitis B and C viruses, vaccination against human papilloma viruses in boys and advances on intranasal live‑attenuated vaccination against influenza. Emphasis was also given to the role of probiotics in the management of viral infections in childhood, the potential association between viral infections and the pathogenesis of asthma, fetal and neonatal brain imaging and the paediatric intensive care of children with central nervous system viral infections. Moreover, an interesting overview of the viral causes of perinatal mortality in ancient Greece was given, where recent archaeological findings from the Athenian Agora's bone well were presented. Finally, different continuing medical educational options in Paediatric Virology were analysed and evaluated. The present review provides an update of the key topics discussed during the workshop.

Mother-to-child transmission of hepatitis B and C virus: review of the epidemiology and current treatment options

Hepatitis B and C viruses are the leading causes of liver-related morbidity and mortality throughout the world. Hepatitis B virus is predominantly transmitted perinatally, particularly in endemic areas. The rate of mother-to-child transmission of hepatitis C virus is on the rise, largely due to the increasing opioid epidemic. While there are guidelines established for the screening and treatment of pregnant females at risk for chronic hepatitis B infection, there no such guidelines or treatment options available in pregnant females with chronic hepatitis C infection. This review examines the epidemiology of mother-to-child transmission of chronic hepatitis B and C as well as the current treatment options during pregnancy and breastfeeding for both.

Management of Pregnant Women and Children: Focusing on Preventing Mother-to-Infant Transmission

Hepatitis B virus (HBV) immunization has been effectively preventing chronic HBV infection with >90% efficacy in countries with universal neonatal immunization. Perinatal mother-to-infant transmission of HBV remains the major cause of chronic HBV infection despite immunization. Maternal hepatitis B e-antigen (HBeAg) and high viral load have been noted to be the most important risk factors for transmission. In recent years, short-term antiviral therapy for pregnant women in the third trimester has been shown to be highly effective in reducing 90% of vaccine failure in children. It is important to monitor maternal aminotransferase elevations postpartum. Long-term outcome of mothers and children is needed and awaits further investigations. Despite the above-mentioned preventive measures, it is also important to monitor high-risk children at 1 year of age with hepatitis B surface antigen and anti-hepatitis B to identify those with chronic HBV infection. Most of the children with chronic HBV infection were in the immune-tolerant phase. The goals for antiviral treatment in children are to reduce severity of liver injury, achieve HBeAg seroconversion, and prevent development of liver fibrosis and cancer. Studies on antiviral therapy are undergoing to elucidate the optimal indication and drug treatment for children. The ideal future goal of treatment is to eradicate chronic HBV infection globally.