CSOG MFM Committee Guideline: Management of Hepatitis B During Pregnancy and Prevention of Mother-to-Child Transmission of Hepatitis B Virus (2020)

Screening for viral hepatitis carriage

Viral hepatitis during pregnancy is common globally. In this review, we focus on the antenatal screen for hepatitis A, B, C and E, the prevention of mother-to-child transmission (MTCT) of hepatitis B and C, and the management of hepatitis A, B, C and E during pregnancy. Neonatal timely administration of hepatitis B immunoglobulin and hepatitis B vaccine is the cornerstone for preventing MTCT of hepatitis B virus (HBV), and perinatal antiviral prophylaxis with tenofovir disoproxil fumarate in mothers with positive HBeAg or HBV DNA >2 × 105 IU/ml also plays important roles in further reducing MTCT. Avoidance of risk practices in managing labor and delivery process of women with HCV infection may be useful to reduce MTCT of HCV. Early recognition of severe hepatic injury or liver failure associated with hepatitis viruses by regular liver function tests is critical to prevent maternal mortality associated with hepatitis.

Can newborn infants with positive HIV soon after birth be diagnosed with intrauterine infection?

BACKGROUND

Mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) can occur intrauterine, intrapartum, and postpartum. Currently, infants with confirmed positive results in virological tests before 48 h of age are defined as having intrauterine infection.

AIM

We herein review the literature that identifies emerging challenges in diagnosing intrauterine HIV infection to rethink the current diagnostic criteria.

FINDINGS

A number of reports have shown that some infants who were diagnosed with intrauterine HIV infection after birth became negative for HIV in the subsequent follow-ups, including negative HIV antibodies at the age of 12-18 months. Such "clearance" of HIV was attributed to various reasons: neonatal antiretroviral treatment (ART), false positivity, strong host immune response, or unknown factors in maternal breast milk.

DISCUSSIONS

Positive HIV tests in newborn infants shortly after birth do not necessarily indicate HIV infection, because maternal HIV can enter fetal circulation intrapartum due to the repetitive, strong uterine contractions. The infants are therefore exposed to, but may not yet be infected with HIV at that time. The current diagnostic criteria cannot differentiate HIV exposure from HIV infection, leading to so-called "challenges in diagnosing intrauterine HIV infection". Those infants diagnosed with intrauterine infection who cleared HIV later were less likely to have been truly infected with HIV, but more likely to have been exposed to HIV. Moreover, we suggest that the determination of HIV antibody titers in infants' serial serum samples can provide valuable information to distinguish intrapartum exposure from intrauterine infection.

Timing of the First Dose of the Hepatitis B Vaccine in Preterm Infants

Introduction: The World Health Organization (WHO) recommends all newborn infants receive the first dose of the hepatitis B vaccine within 24 h of birth irrespective of maternal hepatitis B carrier status. However, the physiological immaturity of the immune system in preterm infants may influence the immune responses to the vaccine particularly in the first few days and weeks of life, and adverse events may occur following vaccination that are not observed in infants born at term. Objectives: To review existing published guidelines surrounding timing of the first dose of the hepatitis B vaccine in preterm infants born to hepatitis B surface antigen negative (HBsAg-negative) mothers. Methods: A search was performed for relevant papers and guidelines published between January 2002 and July 2022 on the Ovid MEDLINE and Embase databases and through targeted searches. Two authors independently reviewed the search results to identify relevant sources, which were then analysed and described through narrative synthesis. Results: Twenty-seven relevant papers and guidelines regarding 15 countries and regions were included. Of these, 13.3% of guidelines, which represented 16.8% of the overall population of 4.1 billion people covered by the identified guidelines, recommended a nationwide birth dose of the hepatitis B vaccine to all preterm infants. In 40.0% of guidelines (77.9% of the overall population), the birth dose was only recommended for infants with a birth weight of more than 2000–2200 g. Another 33.3% of countries and regions (covering 4.4% of the population) recommended no universal birth dose for all infants, including preterm infants, whilst 13.3% (1.0% of the population) had guidelines that varied between jurisdictions and hospitals within their country/region. Conclusions: Existing guidelines surrounding the timing of the first dose of the hepatitis B vaccine in preterm infants vary substantially between countries and regions. Further research comparing the immunogenicity and safety of different hepatitis B vaccine schedules is needed to provide concrete evidence to provide guidance regarding the timing of vaccination against hepatitis B in preterm infants.

Efficacy of the hepatitis B vaccine alone in the prevention of hepatitis B perinatal transmission in infants born to hepatitis B e antigen-negative carrier mothers

Background

Vertical mother-to-child transmission (MTCT) of the hepatitis B virus (HBV) remains an important issue. Timely administration of hepatitis B immunoglobulin (HBIG) and of the HBV vaccine is effective in preventing MTCT in infants born to HBV-infected mothers. However, HBIG is often not easily available in low-income countries or regions.

Methods

We compared in a retrospective cohort study the HBV vaccine efficacy alone and in combination with HBIG in preventing vertical MTCT in infants born to HBeAg-negative carrier mothers in Jiangsu province, China. Based on the administration of the HBV vaccine and HBIG shortly after birth, children were divided into two groups: Group 1, administration of the HBV vaccine alone, and Group 2, concurrent use of HBIG and of the HBV vaccine.

Results

A total of 620 infants born to HBeAg-negative carrier mothers were enrolled into this study. Group 1 included 195 children who had received the HBV vaccine alone after birth, and Group 2, 425 children who had received both HBIG and the HBV vaccine. Children were followed up to the age of 68 and 42 months, respectively. MTCT of HBV occurred in 0% (0/195) in Group 1 (HBV vaccine alone) and 0% (0/425) in Group 2 (HBV vaccine and HBIG) (p = 1.00).

Conclusion

In this retrospective cohort study, we found that HBV vaccination alone shortly after birth was effective in preventing MTCT of HBV in infants born to HBeAg-negative carrier mothers.

Hepatitis B Viral Markers in the Human Milk of HBsAg-Positive Mothers: An Observational Study

BACKGROUND

Quantification of viral antigens and viral loads in human milk samples from mothers infected with hepatitis B virus is largely unknown.

RESEARCH AIM

The aim of the study was to quantitatively measure the levels of viral antigens and deoxyribonucleic acid of hepatitis B virus in human milk from mothers infected with hepatitis B virus.

METHODS

Fifty-five pairs of milk and serum samples from mothers with positive hepatitis B surface antigen, including 11 hepatitis B e antigen positive, were quantitatively tested to measure viral antigens by microparticle enzyme immunoassay and viral loads by real-time polymerase chain reaction assay.

RESULTS

The median level of hepatitis B surface antigen in the human milk samples of mothers with positive or negative hepatitis B e antigen was each lower than that in the sera, respectively (1.10 vs. 4.32 log₁₀ IU/ml, t = 10.693, p < .001; -0.77 vs. 2.53 log₁₀ IU/ml, t = -25.135, p < .001). The titers of hepatitis B surface antigen or hepatitis B e antigen in the human milk samples were each correlated with that in maternal serum. The detectable level of deoxyribonucleic acid of hepatitis B virus in human milk ranged from 1.42-5.27 log₁₀ IU/ml, whereas that in maternal sera was 1.44-8.66 log₁₀ IU/ml. The viral level in human milk was not correlated with that in maternal circulation.

CONCLUSION

The present study data illustrate the relatively low titers of viral markers in the milk of mothers with positive hepatitis B surface antigen.

Inhibition of In Vitro Infection of Hepatitis B Virus by Human Breastmilk

Despite the presence of hepatitis B virus (HBV) in the human breastmilk of mothers infected with HBV, it has been shown that breastfeeding does not increase the risk of mother-to-child transmission (MTCT) of HBV. We tested the hypothesis that human breastmilk may contain active components that bind to HBV and inhibit the infectivity of HBV. The results show that human whey significantly inhibited the binding of the hepatitis B surface antigen (HBsAg) to its antibodies in competitive inhibition immunoassays. The far-western blotting showed that HBsAg bound to a protein of 80 kD in human whey, which was identified as lactoferrin by mass spectrometry. Competitive inhibition immunoassays further demonstrated that both human lactoferrin and bovine lactoferrin bound to HBsAg. Human whey, human lactoferrin, and bovine lactoferrin each significantly inhibited the infectivity of HBV in vitro. Our results indicate that human breastmilk can bind to HBsAg and inhibit the infectivity of HBV, and the active component is lactoferrin. The findings may explain the reason that breastfeeding has no additional risk for MTCT of HBV, although human breastmilk contains HBV. Our study provides experimental evidence that HBV-infected mothers should be encouraged to breastfeed their infants

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

OBJECTIVE

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

DATA SOURCES

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

STUDY ELIGIBILITY CRITERIA

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

METHODS

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

RESULTS

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

CONCLUSION

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

Asian Pacific association for the study of liver (APASL) guidelines: hepatitis B virus in pregnancy

Hepatitis B virus (HBV) infection still remains a major public health issue in the Asia-Pacific region. Most of the burden of HBV-related disease results from infections acquired in infancy through perinatal or early childhood exposure to HBV in Asia-Pacific. Hepatitis B during pregnancy presents unique management issues for both the mother and fetus. These APASL guidelines provide a comprehensive review and recommendations based on available evidence in the literature, for the management of females with HBV infection through every stage of pregnancy and postpartum. These also address the concerns, management challenges, and required follow-up of children born to hepatitis B-positive mothers.

Elimination of hepatitis B virus infection in children: experience and challenge in China

ABSTRACT

Chronic hepatitis B virus (HBV) infection is a serious health issue because of its severe sequelae. Prevention of mother-to-child transmission (MTCT) of HBV is critical to eliminate chronic HBV infection. Here, we reviewed the progress toward the elimination of HBV infection in children in China in the recent decade. A universal hepatitis B vaccination program started from 2002 has been intensified, with the coverage of timely birth dose >95% of all newborn infants from 2012. Since 2011, China has taken a nationwide program to administer hepatitis B immunoglobulin (HBIG) with free of charge in all neonates of HBV-infected mothers, leading to a significant increment of timely use of HBIG. The prevalence of hepatitis B surface antigen (HBsAg) was declined from around 10% among children in 1980s to <0.5% among children born after 2011. Administration of oral antiviral agents in HBV-infected pregnant women with HBV DNA >2 × 105 U/mL during the third trimester is increasing, which will further reduce MTCT of HBV. However, there are some challenges in the elimination of HBV infection in children, which need to overcome by the concerted efforts. Nevertheless, it is anticipated that China will achieve the goal set by the World Health Organization that the prevalence of HBsAg in children aged <5 years is ≤0.1% by 2030.

Reduced mother-to-child transmission of hepatitis B after implementation of completely charge-free active-passive immunoprophylaxis: an observational cohort study

Objectives: China has implemented universal hepatitis B vaccination since 2002 and provided charge-free hepatitis B immunoglobulin (HBIG) to infants of HBV-infected mothers since July 2011. We aimed to compare mother-to-child transmission (MTCT) in children born before and since July 2011.Methods: In total, 5,149 children of HBV-infected mothers were tested for HBV markers. Group one contained 1,160 children born during August 2002-June 2011 and group two contained 3,989 children born during July 2011-June 2016.Results: In total, 92 (1.8%, 95% confidence interval [95%CI] 1.4-2.2) children were infected with HBV. None (0%, 95%CI 0.0-0.1) of 3,716 children of mothers with negative hepatitis B e antigen (HBeAg) was infected, whereas 92 (6.4%, 95%CI 5.2-7.8) of 1,433 children of HBeAg-positive mothers were infected (p < 0.0001). Among children of HBeAg-positive mothers, MTCT occurred in 10.3% (19/185) (95%CI 6.3-15.6) in group one and 5.8% (73/1,248) (95%CI 4.6-7.3) in group two (p = 0.02).Conclusions: Implementing charge-free active-passive immunoprophylaxis greatly reduces MTCT of HBV in children of HBeAg-positive mothers, highlighting the importance of timely administration of both hepatitis B vaccine and HBIG to prevent MTCT. The still remaining MTCT suggests that reducing maternal virus load before delivery is an additional important measure.