Maternal Hepatitis B Virus DNA Research Articles

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

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. 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. 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. 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). 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.

Evaluation of the Efficacy and Safety of Tenofovir Disoproxil Fumarate in Intercepting Mother-to-Child Transmission of Hepatitis B Virus.

Vertical transmission of hepatitis B virus (HBV), especially in Asia, is a key target in the global elimination of HBV. This study assessed the effects of tenofovir disoproxil fumarate (TDF) in pregnant women for mother-to-infant transmission of HBV. A total of 122 pregnant women at our hospital met the inclusion criteria for high HBV DNA viral loads. They were randomly divided into TDF-treatment (n=70) and placebo (n=52) groups. Maternal liver function and serum HBV DNA load were tested before and after treatment. Clinical and laboratory data of infants were assayed at delivery and 7-months post-partum visit and compared between the two groups. There was no difference in clinical characteristics of participants between the two groups. There were no significant differences in liver function markers, including alanine aminotransferase, total bilirubin, blood creatinine, and blood urea nitrogen levels before and after TDF treatment. The serum HBV DNA viral load of the TDF-treated group became significantly lower than those of the control group and their own pre-medication levels. Infants showed no significant difference in body growth, including weight, height, head size, and five-min Apgar score. At 7 months after birth, 94.29% of infants in the TDF group and 86.54% of control-group infants had protective HBsAb levels ≥ 10 mIU/ml (p>0.05). The HBV infection rate of infants in the TDF-treated group was lower than that in the non-treated group. In high-HBV-DNA-load pregnant women, TDF administered from 28 weeks gestational age to delivery was associated with a lower risk of mother-to-infant transmission of HBV.

Association of vitamin D and polymorphisms of its receptor with antiviral therapy in pregnant women with hepatitis B.

The interruption of mother-to-child transmission (MTCT) is considered important to decrease the individual and population morbidity of hepatitis B virus (HBV) infection as well as the global burden of hepatitis B. Serum vitamin D (VD) is associated with hepatitis B. To assess whether baseline VD levels and single nucleotide polymorphisms of the VD receptor gene (VDR SNPs) are associated with the efficacy of tenofovir disoproxil fumarate (TDF) in the prevention of MTCT in pregnant women with high HBV viral loads. Thirty-eight pregnant women who were at high risk for MTCT of HBV (those with an HBV DNA level ≥ 2 × 105 IU/mL during 12-24 wk of gestation) receiving antiviral therapy of TDF between June 1, 2019 and June 30, 2021 in Mianyang were included in this retrospective study. The women received 300 mg TDF once daily from gestational weeks 24-28 until 3 mo after delivery. To further characterize the clinical relevance of maternal serum HBV DNA levels, we stratified patients according to HBV DNA level as follows: Those with levels < 2 × 105 (full responder group) vs those levels ≥ 2 × 105 IU/mL (partial responder group) at delivery. Serum levels of 25-hydroxyvitamin D [25(OH)D], liver function markers, virological parameters, VDR SNPs and other clinical parameters were collected to analyze their association with the efficacy of TDF. The Mann-Whitney U test or t test was used to analyze the serum levels of 25(OH)D in different groups. Multiple linear regressions were utilized to analyze the determinants of the maternal HBV DNA level at delivery. Univariate and multivariate logistic regression analyses were employed to explore the association of targeted antiviral effects with various characteristics at baseline and delivery. A total of 38 pregnant women in Mianyang City at high risk for MTCT of HBV were enrolled in the study. The MTCT rate was 0%. No mother achieved hepatitis B e antigen or hepatitis B surface antigen (HBsAg) clearance at delivery. Twenty-three (60.5%) participants were full responders, and 15 (39.5%) participants were partial responders according to antiviral efficacy. The present study showed that a high percentage (76.3%) of pregnant women with high HBV viral loads had deficient (< 20 ng/mL) or insufficient (≥ 20 but < 31 ng/mL) VD levels. Serum 25(OH)D levels in partial responders appeared to be significantly lower than those in full responders both at baseline (25.44 ± 9.42 vs 17.66 ± 5.34 ng/mL, P = 0.006) and delivery (26.76 ± 8.59 vs 21.24 ± 6.88 ng/mL, P = 0.044). Serum 25(OH)D levels were negatively correlated with maternal HBV DNA levels [log(10) IU/mL] at delivery after TDF therapy (r = -0.345, P = 0.034). In a multiple linear regression analysis, maternal HBV DNA levels were associated with baseline maternal serum 25(OH)D levels (P < 0.0001, β = -0.446), BMI (P = 0.03, β = -0.245), baseline maternal log10 HBsAg levels (P = 0.05, β = 0.285) and cholesterol levels at delivery (P = 0.015, β = 0.341). Multivariate logistic regression analysis showed that baseline serum 25(OH)D levels (OR = 1.23, 95%CI: 1.04-1.44), maternal VDR Cdx2 TT (OR = 0.09, 95%CI: 0.01-0.88) and cholesterol levels at delivery (OR = 0.39, 95%CI: 0.17-0.87) were associated with targeted antiviral effects (maternal HBV DNA levels < 2 × 105 at delivery). Maternal VD levels and VDR SNPs may be associated with the efficacy of antiviral therapy in pregnant women with high HBV viral loads. Future studies to evaluate the therapeutic value of VD and its analogs in reducing the MTCT of HBV may be justified.

Follow-Up of Newborns with Hepatitis B Antigenemia.

There is a need for data to evaluate hepatitis B antigenemia in newborns of mothers with hepatitis B virus (HBV) infection. This study aims to investigate this. Newborns with positive serum hepatitis B surface antigen (HBsAg) and/or e antigen (HBeAg) were enrolled in the study. One hundredand one newborns from 98 HBV-infected mothers were included. Median maternal serum HBV DNA level was 23,200IU/mL at delivery. Among the newborns, 48 were boys and 53 were girls. Mean birth weight was 3190.5g. Twenty-one newborns had concurrent seropositive HBsAg and HBeAg, nine had seropositive HBsAg and seronegative HBeAg, and 71 had seronegative HBsAg and seropositive HBeAg. Eight newborns had detectable serum HBV DNA. In the follow-up, serum HBsAg and HBeAg in the newborns with undetectable HBV DNA became negative before 6months of age. Two infants with detectable HBV DNA were diagnosed with immunoprophylaxis failure, one of whom developed active hepatitis at 3months of age. Liver biopsy in this case showed significant interface hepatitis, fibrous septa formation, and expansion of portal areas with occasional bridging fibrosis. Concurrent HBV viremia and antigenemia in newborns of HBV-infected mothers requires attention, while antigenemia without viremia is often transient.

Incidence of mother-to-child transmission of hepatitis B in relation to maternal peripartum antiviral prophylaxis: Asystematic review and meta-analysis.

Mother-to-child transmission (MTCT) of the hepatitis B virus (HBV) is a serious public health challenge. Estimating HBV MTCT incidence by region under different prophylaxis regimens is critical to understanding the regional disease burden and prioritizing interventions. This study aimed to calculate HBV MTCT incidence under different prophylaxis regimens globally and regionally and identify the HBV DNA threshold for maternal peripartum antiviral prophylaxis. This review was registered in advance in PROSPERO (CRD 42019120567). We searched PubMed, Embase, China National Knowledge Infrastructure, ClinicalTrials.gov, and Cochrane Library databases for studies on MTCT in pregnant women with chronic HBV infection from their inception until June 13, 2022. MTCT was defined as hepatitis B surface antigen (HBsAg) or HBV DNA seropositivity in infants aged 6-12 months. We calculated the pooled HBV MTCT incidence using the DerSimonian-Laird random-effects model. Among 300 studies, 3402 of 63 293 infants had HBV due to MTCT. Without prophylaxis regimens, the pooled HBV MTCT incidence was 31.3%, ranging from 0.0% (95% confidence interval [CI] 0.0%-6.0%; European Region) to 46.1% (95% CI 29.7%-63.0%; Western Pacific Region). Following the introduction of the hepatitis B vaccine, the HBV MTCT incidence decreased from 82.9% to 15.9% in HBeAg-positive women and from 10.3% to 2.3% in HBeAg-negative women. Maternal peripartum antiviral treatment alongside infant immunoprophylaxis further decreased MTCT incidence to 0.3% (95% CI 0.1%-0.5%). Despite infant immunoprophylaxis, the incidences of MTCT at maternal HBV DNA levels of <2.30, 2.00-3.29, 3.00-4.29, 4.00-5.29, 5.00-6.29, 6.00-7.29 and ≥7.00 log10 IU/ml were 0.0% (95% CI 0.0%-0.0%), 0.0% (95% CI 0.0%-0.0%), 0.0% (95% CI 0.0%-0.5%), 0.6% (95% CI 0.0%-2.6%), 1.0% (95% CI 0.0%-3.1%), 4.3% (95% CI 1.8%-7.5%), and 9.6% (95% CI 7.0%-12.5%), respectively. HBV MTCT incidence varies across regions. The Western Pacific Region bears the heaviest burden. Peripartum antiviral prophylaxis plus infant immunoprophylaxis is promising for interrupting HBV MTCT. Regarding the HBV DNA threshold for peripartum antiviral prophylaxis, maternal HBV DNA of 4.00 log10 IU/ml or greater seems justified.

Characterization of Hepatitis B Virus in Tenofovir-Treated and Untreated Chronically Infected Mothers and Their Immunoprophylaxis Failure Infants.

Maternal tenofovir disoproxil fumarate (TDF) therapy during late pregnancy can reduce mother-to-infant transmission of hepatitis B virus (HBV). We investigated HBV mutations associated with maternal TDF therapy and their role in infant immunonophylaxis failure (IPF). Serum samples from untreated (n = 89) and TDF-treated (n = 68), highly viremic, chronically infected mothers and their infants were analyzed for HBV DNA by nested polymerase chain reaction (PCR) and direct sequencing. At delivery, compared with untreated mothers, TDF-treated mothers had a lower HBV DNA titer and a higher frequency of basal core promoter (BCP) gene mutations, but they had similar frequencies in pre-S/S and pre-core/core mutations. The 14 mothers harboring surface "a" determinant mutants did not transmit the mutants to their immunized infants. Such mutants were found in 3 of 13 IPF infants; the 13 mothers had wild-type hepatitis B surface antigen (HBsAg). In univariable analysis, maternal HBV DNA titer (odds ratio [OR]: 1.54; 95% confidence intervals [CI]: 1.02-2.33; P = .039), genotype C (OR: 4.18; 95% CI: 1.28-13.62; P = .018) and pre-S1 wild-type sequence (OR: 6.33; 95% CI: 1.85-21.68; P = .003) at delivery were associated with infant IPF. Multivariable analyses showed that maternal genotype C (OR: 3.71; 95% CI: 1.11-12.36; P = .033) and pre-S1 wild-type (OR: 6.34; 95% CI: 1.79-22.44; P = .004) were associated with infant IPF independently of maternal viremia. Along with high maternal HBV DNA titer at delivery, maternal genotype C and pre-S1 wild-type sequence were potential risk factors for infant IPF, although BCP mutations were not. The offspring of pregnant women harboring "a" determinant mutants as major strains seemed to be protected by immunoprophylaxis. NCT01312012.

Efficacy of Birth Dose Vaccination in Preventing Mother-to-Child Transmission of Hepatitis B: A Randomized Controlled Trial Comparing Engerix-B and Sci-B-Vac.

Background and aims: Peripartum transmission of hepatitis B virus (HBV) from an infected mother to the child can be prevented in most but not all cases by immediate vaccination of the newborn. The aim of this study was to compare the efficacy of two licensed hepatitis B vaccines, Engerix-B versus Sci-B-Vac, in preventing peripartum HBV transmission. Methods: A prospective multicenter randomized controlled study in 4 delivery centers was performed from 2009 to 2014. HBsAg positive pregnant women and their newborns were recruited at the delivery rooms. All newborns received Hepatitis B Immune Globulin within 10 h after birth, as well as active HBV vaccination at 0, 1 and 6 months of age. Maternal assessment at delivery included transaminases, blood count, international normalized ratio and viral status. Infants were tested for HBsAg, anti-HBc and anti-HBs at 12 months of age. Results: In the intention to treat (ITT), 171 infant and mother pairs fulfilled the study enrollment criteria and completed follow up, 82 received Engerix-B and 89 Sci-B-Vac. Maternal parameters and viral status were similar in both groups. At 12 months of age, the Sci-B-Vac group had lower HBsAg carriage rates (1/89, 1.1%) than the Engerix-B group (5/82, 6.1%) with borderline significance (risk difference of −0.05, 95% CI −0.11–0.007, t-test = 0.05), and borderline significance lower vaccine failure rates with anti-HBs < 10 mIU/mL in the Sci-B-Vac (2/89, 2.2%) than in the Engerix-B (8/82, 9.8%, p = 0.05). Higher seroprotection rates were found in the Sci-B-Vac group with all anti-HBs titer stratifications of >10 mIU/mL (p = 0.05), >100 mIU/mL (p = 0.05) and >1000 mIU/mL (p = 0.01). Active/passive vaccination was effective in 10/13 cases with maternal HBV DNA levels > 7 log10 IU/mL up to 9.5 log10 IU/mL, but failed in 3 cases for unknown reasons. Conclusion: Sci-B-Vac was superior to Engerix-B in preventing peripartum HBV transmission in neonates from HBsAg+ mothers and induces significantly higher anti-HBs levels. NIH registration number: NCT 01133184.

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

Hepatitis B virus (HBV) infection caused by mother-to-child transmission (MTCT) continues to pose challenges to global health. This study aimed to assess the efficacy and safety of tenofovir disoproxil fumarate (TDF) for preventing HBV MTCT. PubMed and the Cochrane Central Register of Controlled Trials were searched through August 2020. Randomised controlled trials (RCTs) were selected that evaluated the efficacy and safety of TDF for preventing MTCT of HBV compared with the standard of care, placebo or other HBV therapies. The primary outcomes were HBV MTCT rate and maternal HBV DNA level. Secondary outcomes were infant and maternal safety outcomes. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines, and prospectively registered on PROSPERO (CRD42020186275). Of 240 citations, three RCTs that involved 651 participants were included. The pooled result showed that TDF can reduce the risk of HBV MTCT after 6 months postpartum by 80% (risk ratio [RR]0.2, 95% confidence interval [CI 0.06-0.7], n=584) with low heterogeneity (I2 =0%). TDF demonstrated HBV DNA suppression at delivery, though there was heterogeneity among individual studies (RR0.13, 95% CI [0.08-0.20] and (RR0.36, 95% CI [0.27-0.49]). Maternal and infant safety outcomes were comparable among treated and untreated mothers and infants born to them. The quality of evidence varied from high to very low. There is evidence that TDF effectively interrupted MTCT of HBV and suppressed HBV DNA level. Available studies on safety are very limited and heterogeneous, emphasising the need for additional RCTs with complete safety indicators.

1055. Assessing the Impact of the Routine Childhood Hepatitis B Immunization and the Need for Hepatitis B Vaccine Birth Dose in Sierra Leone, 2018

BackgroundAll African countries recommend 3 doses of hepatitis B vaccine (HepB3), most at 6, 10, and 14 weeks of age, but few recommend a HepB birth dose (HepB-BD). To evaluate the role of mother to child transmission (MTCT) of hepatitis B virus (HBV) with the 3 dose HepB schedule, we conducted a serosurvey in Sierra Leone among 4–30 month old children and their mothers, and 5–9 year old children.MethodsWe conducted a multi-stage cluster survey in 3 districts. Enumeration areas (EA) were selected by probability proportional to size, followed by random selection of eligible households to identify 1901 children per age group. We tested all participants for HBV surface antigen (HBsAg) by rapid test and collected children’s HepB vaccination history. Serum from all HBsAg+ mothers and 1 HBsAg- mother per EA was tested for total antibodies to HBV core antigen (anti-HBc), HBsAg, HBV e antigen (HBeAg), and HBV DNA. We assessed the association of HBsAg prevalence with HepB vaccination and maternal HBV markers.ResultsAmong 1889 children aged 4–30 months, 20 (1.3%; 95% CI:0.8%–2.0%) were HBsAg+; HepB3 coverage was 85%. Among 2025 children aged 5–9 years, 32 (1.6%; 95% CI:1.1%–2.3%) were HBsAg+; HepB3 coverage was 77%. Of HBsAg+ children, 70% (14/20) of younger and 56% (18/32) of older children received HepB3. Among 1776 mothers of younger children, 169 (9.8%; 95% CI:8.1%–11.7%) were HBsAg+. HBsAg prevalence for children with HBsAg+ mothers was 5.9% (10/169) and 0.7% (6/1605) for those with HBsAg- mothers (adjusted OR=10.6 [95% CI:2.8–40.8]). Of 139 HBsAg+ mothers, 13 (9%) were HBeAg+ and 126 (91%) had detectable HBV DNA. Maternal HBsAg (p=0.026), HBeAg (p< 0.001), and HBV DNA levels ≥ 200,000 IU/mL (p< 0.001) were associated with HBsAg positivity in younger children (Table 1).Table 1: Association of maternal HBV serological and molecular markers with HBsAg positivity in 4–30-month old children — Sierra Leone hepatitis B serosurvey, 2018 ConclusionHBsAg prevalence was much lower among children than among mothers, for whom HepB would not have been available, indicating that routine infant HepB vaccination has substantially lowered HBV burden. Increasing HepB3 coverage could further reduce HBsAg prevalence among children. As HBsAg positivity in young children was strongly associated with having a mother with active HBV infection and > 50% of HBsAg+ children received HepB3, HepB-BD is needed to prevent MTCT of HBV and chronic HBV infections in children.Disclosures All Authors: No reported disclosures

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

Data on tenofovir alafenamide fumarate (TAF) for preventing mother-to-child transmission of hepatitis B virus (HBV) are lacking. To investigate the efficacy and safety of TAF therapy for preventing hepatitis B mother-to-child transmission. 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. 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. 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.

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

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. 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. 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). 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. World Health Organization.

Increased Protection of Earlier Use of Immunoprophylaxis in Preventing Perinatal Transmission of Hepatitis B Virus.

Passive-active immunoprophylaxis against mother-to-child transmission (MTCT) of hepatitis B virus (HBV) recommends administering hepatitis B immunoglobulin (HBIG) and birth-dose hepatitis B vaccine in infants within 12 or 24 hours after birth. With this protocol, MTCT of HBV still occurs in 5-10% infants of HBV-infected mothers with positive hepatitis B e antigen (HBeAg). The present study aimed to investigate whether earlier administration of HBIG and hepatitis B vaccine after birth can further increase protection efficacy. We conducted a prospective, multi-center observational study in infants born to mothers with HBV infection, in whom neonatal HBIG and birth dose hepatitis B vaccine were administered within one hour after birth. The infants were followed up for HBV markers at 7-14 months of age. A total of 1140 pregnant women with HBV were enrolled, and 982 infants (9 twins) of 973 mothers were followed up at 9.6 ± 1.9 months of age. HBIG and birth-dose vaccine were administered in newborn infants within a median of 0.17 (0.02-1.0) hours after birth. The overall rate of MTCT was 0.9% (9/982), with none (0%) of the 607 infants of HBeAg-negative mothers and 9 (2.4%) of 375 infants of HBeAg-positive mothers acquiring HBV. All 9 HBV-infected infants were born to mothers with HBV DNA >2.75 × 106 IU/mL. Maternal HBV DNA levels >2 × 106 IU/mL were an independent risk factor (odds ratio, 10.627; 95% confidence interval, 2.135-∞) for immunoprophylaxis failure. Earlier use (within 1 hour after birth) of HBIG and hepatitis B vaccine can provide better protection efficacy against MTCT of HBV.

Relationship between mutations of HBV basal core promoter region in HBsAg-positive mothers and intrauterine transmission

Objective: To analyze the relationship between maternal mutations in basal core promoter region of hepatitis B virus (HBV) genotype C and intrauterine transmission. Methods: We collected information on general demographic characteristics and process of delivery among 399 pairs of consecutive HBsAg-positive mothers and their neonates, from the Third People's Hospital of Taiyuan in Shanxi province, China. Fluorescence quantitative polymerase chain reaction (FQ-PCR) and Electro-chemiluminescence immuno-assay (ECLIA) kits were used to detect both maternal and neonatal HBV DNA and serological markers in the peripheral blood. From 113 mothers with HBV DNA load ≥10(6) IU/ml, we selected 22 mothers whose neonates were with intrauterine transmission and randomly selected the same number of mothers whose neonates were without intrauterine transmission, as controls. The whole-length HBV DNA were extracted, amplified, cloned, sequenced and genotyped. Finally, a total of 39 mothers with genotype C of HBV were selected for mutation analysis. Results: Thirty-nine cases of genotype C (88.63%) were finally included in the study, with 19 cases in the intrauterine transmission group and 20 cases as controls. Rates of A1762T/G1764A double mutations were significantly different between the intrauterine transmission group and the control group (7.53% vs. 27.72%, P<0.001). Results from the multivariate analysis showed that the A1762T/G1764A double mutations had reduced the risk of intrauterine transmission (aOR=0.065, 95%CI: 0.006-0.746, P=0.028). Maternal A1762T/G1764A double mutations appeared to be possibly associated with neonatal HBeAg (P=0.050). Conclusion: A1762T/G1764A double mutations of HBV DNA from the genotype C of those HBsAg-positive mothers could reduced the risk of HBV intrauterine transmission during pregnancy.

Hepatitis B - Vertical transmission and the prevention of mother-to-child transmission.

Hepatitis B virus (HBV) infection is the commonest cause of chronic hepatitis, with an estimated global prevalence of 3.5%, and which leads to significant morbidity and mortality. Mother-to-child transmission (MTCT) during pregnancy is the leading form of transmission in endemic populations, and its interruption is thus crucial as the initial step in the elimination of HBV infection, notwithstanding the availability of potent antiviral medications. The risk of MTCT is dramatically reduced by timely neonatal HBV vaccination and the administration of hepatitis B immunoglobulin after birth in high-risk infants. Maternal HBV DNA quantification during pregnancy allows the assessment of the risk of newborn immunoprophylaxis failure (IF). Maternal antiviral treatment in highly viremic women can reduce the risk of IF. However, the optimal HBV DNA cutoff level for the initiation of antiviral treatment remains to be determined.

1105 Tenofovir Disoproxil Fumarate (TDF) to Prevent Hepatitis B Transmission in Mothers With High Viral Load in a Real World U.S. Cohort

INTRODUCTION: Maternal TDF treatment during the third trimester has been shown to reduce perinatal transmission of the hepatitis B virus (HBV) in highly viremic women in several RCTs. However, the data is limited on the effectiveness of TDF in the real-world setting. With this real-world study, we aimed to assess the efficacy and safety of TDF therapy for these mothers in a single center in the US. METHODS: All Hepatitis B e-antigen positive mothers with HBV DNA &gt;6log10 copies/mL who received TDF in the third trimester and delivered from July 2010 to September 2018 were retrospectively analyzed. All infants received hepatitis B immunoglobulin and vaccination at birth and subsequently. Primary endpoints were the safety of TDF use and mother-to-child transmission rates. Secondary outcomes were maternal HBV DNA level suppression at delivery. RESULTS: Among the 75 patients enrolled, the mean (±SD) age of the patients was 30.47 ± 4.49 years, mean (±SD) gestational age was 37.87 ± 2.95 weeks, and the mean (±SD) treatment duration before delivery was 9.60 ± 3.36 weeks. A significantly lower level of the mean (±SD) serum HBV DNA was achieved at delivery vs. baseline (4.2 ± 1.2 vs. 7.6 ± 0.80 log10 copies/mL, respectively; P- &lt; 0.01). Additionally, 80% (60/75) of mothers achieved HBV DNA &lt; 6log10 copies/mL at delivery. The median (Interquartile range) alanine aminotransferase (ALT) level before treatment was 26 (20) IU/L, and at delivery was 27 (20) IU/L respectively. Vertical transmission rate among infants was 0%, and all infants were hepatitis B surface antigen negative between 28 -52 weeks after birth. Fatigue was the most common complaint reported by 52% (39/75) of mothers. No infants had a birth defect. On treatment, ALT flares were observed in 4.5% (6/75) of mothers. CONCLUSION: In this US cohort of real-world practice, TDF therapy for highly viremic mothers was well tolerated and reduced vertical transmission effectively. No severe adverse effects were reported in both mothers and infants. Our study supports the use of TDF treatment for highly viremic mothers in a real-world setting.

Reduced Mother-to-Child Transmission of Hepatitis B after Implementation of Completely Charge-Free Immunoprophylaxis in Mainland China

Background: Passive-active immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine is recommended to prevent mother-to-child transmission (MTCT) of hepatitis B virus (HBV). China has taken a policy to provide charge-free HBIG for infants of HBV-infected mothers since July 2011. We analyzed HBV infection rate in children of HBV-infected mothers born before and since July 2011 in real-life practice. Methods: Totally 5149 children of 5004 HBV-infected mothers, 1160 children born before July 2011 and 3989 children born since July 2011, across Jiangsu province, China, were followed up for HBV markers at 0⋅6-8 years age from 2009 to 2018. Findings: Totally 92 children were HBsAg positive, with an overall infection rate 1⋅79%. MTCT occurred in 0% of 3716 children of hepatitis B e antigen (HBeAg)-negative mothers, and in 6⋅42% of 1433 children of HBeAg-positive mothers (p<0⋅0001). Among 1433 children of HBeAg-positive mothers, transmission occurred in 10⋅27% born before July 2011 and 5⋅5% born since July 2011 (p=0⋅0221); HBIG and vaccine were timely administered in 76⋅47% and 92⋅67% of children born before July 2011 respectively, and in 98⋅02% and 98⋅32% of those born since July 2011 respectively (each p<0⋅0001). Among 1433 children of HBeAg-positive mothers, MTCT occurred in 75 (5⋅54%) of 1355 children with recommended immunoprophylaxis, and in 17 (21⋅79%) of 78 children not per recommended immunoprophylaxis (p<0⋅0001). The lowest HBV DNA level associated with transmission was 3⋅08ₓ106 IU/mL. Interpretation: In addition to maternal HBeAg positive, inappropriate administration of HBIG and/or hepatitis B vaccine is a critical risk for MTCT of HBV in children of HBV-infected mothers. Implementation of charge-free HBIG in infants of HBsAg-positive mothers greatly reduces transmission of HBV. Maternal HBeAg negative or HBV DNA ≤106 IU/mL requires no other interventions to prevent MTCT. Funding Statement: This study was supported by the National Health Commission of China (National Key Clinical Research Project 2011271), the National Natural Science Foundation of China (81672002), the Jiangsu Provincial Health Commission (H201537, XK201607), and the Science and Technology Department of Jiangsu Province (BK20161105), China. Declaration of Interests: The authors declare no conflict of interest. Ethical Approval Statement: The present study was approved by the institutional review board of ethics committee in each hospital. Written informed consent was from the mothers or guardians, who also signed the informed consent for children.

Decreased neonatal hepatitis B virus (HBV) viremia by maternal tenofovir treatment predicts reduced chronic HBV infection in children born to highly viremic mothers.

Maternal anti-viral treatment prevents mother-to-infant transmission of hepatitis B virus (HBV), but the role of neonatal viremia on subsequent HBV infection is not clear. To investigate the effect of maternal anti-viral treatment on neonatal serum HBV DNA and hepatitis B surface antigen (HBsAg) in infants born to highly viremic mothers and the roles of neonatal markers in predicting chronic HBV infection in children. Serum HBV DNA and HBsAg were tested in children. Of the 201 pregnant mothers, 110 received tenofovir during the third trimester. Chronic infection in children was defined by HBsAg seropositivity at 6 or 12months lasting more than 6months. The maternal HBV viral loads from baseline to delivery were 8.25±0.48 to 4.29±0.98 log10 IU/mL; and 8.29±0.49 to 8.12±0.68 log10 IU/mL in the tenofovir and control group respectively. Of the 208 children, those in the tenofovir group had a lower rate of neonatal HBV DNA seropositivity at birth (5.22% vs 30.11%, P<0.0001) and HBsAg seropositivity at 6months (1.74% vs 11.83%, P=0.003) and 12months (1.74% vs 10.75%, P=0.007). In a first multivariate analysis, maternal HBV DNA level at delivery (odds ratio=1.70, P=0.0172) and neonatal HBsAg positivity (odds ratio=19.37, P<0.0001) were significantly associated with children's chronic HBV infection. In a second model, neonatal HBV DNA positivity was a strong independent influence variable (odds ratio=61.89, P=0.0002). Maternal tenofovir therapy decreased maternal viral load and neonatal viremia. Positive neonatal HBV DNA was highly correlated with chronic HBV infection in children. Clinical Trial Identifier: NCT01312012.

Issues Meriting Further Study in Preventing Mother-to-Infant Transmission of Hepatitis B by Antiviral Therapy During Pregnancy

Abstract Mother-to-infant transmission of hepatitis B virus (HBV) is a main cause of chronic HBV infection. Maternal high HBV DNA level or positive hepatitis B e antigen (HBeAg) is the major risk factor for the transmission. With recommended passive and active immunoprophylaxis, the transmission occurs in nearly 0 and 4–12% of infants born to HBV-infected mothers with negative and positive HBeAg, respectively. Therefore, pregnant women with negative HBeAg appear not requiring antiviral therapy to prevent mother-to-infant transmission of HBV. Recent studies demonstrated that oral antivirals (lamivudine, telbivudine, or tenofovir) in pregnant women with high viral load or positive HBeAg, starting from 28–32 weeks of gestation, together with neonatal immunoprophylaxis, can almost completely prevent the transmission, indicating that it does not require antiviral therapy before 28 weeks of gestation. Accumulated evidence showed that the antivirals may be stopped upon delivery, and the infants may receive breast feeding after birth. However, these issues, as well as HBV DNA threshold for antiviral therapy during pregnancy, optimal timing for start and discontinuation of antivirals, and the drug safety of fetuses/infants, require further investigations to optimize the antiviral therapy during pregnancy. The proof of safety of fetal exposure to antivirals needs more evidence, which can be achieved from the real-world data analysis.

Mother-to-child transmission of hepatitis B virus after amniocentesis: A retrospective matched cohort study.

The objective of this study is to determine whether amniocentesis increases the risk of mother-to-child transmission (MTCT) of hepatitis B virus (HBV) and evaluate risk factors for MTCT. One hundred forty-three hepatitis B surface antigen (HBsAg)-positive women with amniocentesis were enrolled into the amniocentesis group. Six hundred five nonamniocentesis cases were matched with amniocentesis cases based on maternal viral loads, antiviral therapy regimens, and delivery dates. MTCT of HBV was defined as HBsAg and/or DNA positivity in infants from birth to age 7 to 12 months. Mother-to-child transmission rate was significantly higher in HBsAg-positive women with amniocentesis than in those without amniocentesis (2.80% vs 0.50%; relative risk [RR], 5.64; 95% CI, 1.28-24.93). In the amniocentesis group, maternal HBV DNA more than or equal to 7.0 log10 IU/mL and hepatitis B e-antigen (HBeAg) positivity were associated with higher MTCT rates than maternal HBV DNA less than 7.0 log10 IU/mL (10.81% vs 0%, p = .004) and HBeAg negativity (8.16% vs 0%, p = .013), and antiviral therapy reduced MTCT rate from 14.3% to 0% (p = .554) when maternal HBV DNA was more than or equal to 7.0 log10 IU/mL. Amniocentesis increases the risk of MTCT in women with hepatitis B, and maternal HBV DNA more than or equal to 7.0 log10 IU/mL and HBeAg positivity are risk factors for MTCT. Antiviral therapy may be effective to prevent MTCT after amniocentesis in highly viremic mothers.

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

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. 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. 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. 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. 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.