Tenofovir to Prevent Hepatitis B Transmission in Mothers with High Viral Load

Management of Chronic Hepatitis B in Pregnancy

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

Prevalence of chronic hepatitis B and status of HBV care among rural women who planned to conceive in China

Globally, one third of prevalent chronic hepatitis B (CHB) virus infection (HBV) occurred in China. Assessing the prevalence of CHB infesction and status of HBV-related services among pre-conception women will provide insight into risks of mother to child transmission (MTCT). A cross-sectional analysis of data from the National Free Pre-pregnancy Checkups (NFPC) program in 2010-2014 was conducted. A standardized questionnaire which collected demographic information and enzyme-linked immunosorbent assays (ELISA) which tested serological HBV markers were applied. A total of 16,051,850 rural women aged 15-49 years were included. 5.2% of women were infected with CHB, among whom, 28.6% were also hepatitis B e antigen (HBeAg) positive. The most CHB concentrated places were distributed in southeastern coastal provinces. Women born after 1992 did not experience a higher level of vaccine-induced immunity compared to those born before 1992. Nine in ten rural women with CHB were not aware of their HBV status and a very small proportion of women (0.22%) had received antiviral treatment. Our data demonstrated an overall high-intermediate burden of CHB. Heterogeneity of geographic distribution, high proportion of HBeAg, insufficient awareness of HBV status, and low access to HBV treatment are challenges for preventing the MTCT.

Current status and strategies for hepatitis B control in Korea

Hepatitis B virus (HBV) infection is the most common cause of chronic liver diseases in Korea. After the introduction of the universal HBV vaccination program, the prevalence of hepatitis B surface antigen was markedly reduced, and Korea is now classified as an area of intermediate endemicity for HBV. However, there are still hurdles for elimination of hepatitis B, such as immunoprophylaxis failure against vertical transmission, occurrence of acute hepatitis B among peoples who did not have vaccination at younger age, and rapid increase of immigrant populations from HBV endemic areas. To achieve the World Health Organization goal of viral hepatitis elimination by 2030 in Korea, we suggest comprehensive policies for more effective control of hepatitis B as following: i) insurance coverage for antiviral prophylaxis in mothers with high viremia, ii) screening for hepatitis B seromarkers and catch-up HBV vaccinations of susceptible persons with hepatitis B, iii) establishment of an independent 'viral hepatitis sector' in Centers for Disease Control & Prevention to organize and execute comprehensive strategy for management of viral hepatitis, iv) encourage of management of HBV infection in immigrant populations, v) national campaign to promote awareness of hepatitis B.

Prevention and Care of Hepatitis B in Senegal; Awareness and Attitudes of Medical Practitioners

In highly endemic settings for hepatitis B virus (HBV) infection such as Senegal, access to HBV prevention and care is rapidly evolving. In this context, all medical practitioners should have baseline knowledge on HBV infection and promote access to vaccination, screening, and care. A knowledge and attitudes survey on HBV infection was conducted among a randomly selected sample of medical practitioners in Senegal. Participants were asked to fill-out a questionnaire on the HBV epidemiology, prevention, and treatment. A 60-item knowledge score was computed; the lower quartile of the observed score was used to define poor knowledge. Factors associated with poor knowledge were assessed using a logistic regression model. A total of 127 medical practitioners completed the questionnaire. Only 14 (11.0%) participants knew that HBV vaccine could be safely administered to pregnant women and 65 (51.2%) to newborns. Older practitioners (> 40 years) as well as general practitioners (compared with specialists) were more likely to have a poor knowledge score with odds ratios (ORs) of 3.1 (95% confidence interval [CI] 1.0-9.2) and 2.6 (95% CI 1.0-7.3), respectively. Practitioners who declared not to recommend HBV screening frequently during their consultation were more likely to present a poor knowledge score [OR: 3.0; (95% CI 1.1-8.2)]. As universal HBV screening is being promoted in countries with endemic HBV infection, our finding that poor screening attitudes were associated with a poor knowledge is of concern. There is a need to raise awareness of medical practitioners in Senegal toward universal HBV screening and early vaccination of newborns.

Antiretroviral therapy for pregnant women living with HIV or hepatitis B: a systematic review and meta-analysis

OBJECTIVE

To assess the impact of various antiretroviral/antiviral regimens in pregnant women living with HIV or hepatitis B virus (HBV).

DESIGN

We performed random effects meta-analysis for HIV-related outcomes and network meta-analysis for HBV outcomes, and used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework to assess quality separately for each outcome.

DATA SOURCES

Embase and Medline to February 2017.

ELIGIBILITY CRITERIA

For maternal outcomes, we considered randomised controlled trials (RCTs) comparing tenofovir-based regimens with those with alternative nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs). For child outcomes, we included RCTs and comparative observational studies of tenofovir-based regimens versus alternative NRTIs regimens or, for HBV, placebo.

RESULTS

Ten studies (seven RCTs) met the inclusion criteria for maternal and child outcomes, and an additional 33 studies (12 RCTs) met the inclusion criteria for HBV-specific outcomes. The most common comparison was tenofovir and emtricitabine versus zidovudine and lamivudine. There was no apparent difference between tenofovir-based regimens and alternatives in maternal outcomes, including serious laboratory adverse events (low certainty) and serious clinical adverse events (moderate certainty). There was no difference between NRTIs in vertical transmission of HIV: 1 more per 1000, 8 fewer to 10 more, low certainty; or vertical transmission of HBV: 7 fewer per 1000, 10 fewer to 38 more, moderate certainty. We found moderate certainty evidence that tenofovir/emtricitabine increases the risk of stillbirths and early neonatal mortality (51 more per 1000, 11 more to 150 more) and the risk of early premature delivery at <34 weeks (42 more per 1000, 2 more to 127 more).

CONCLUSIONS

Tenofovir/emtricitabine is likely to increase stillbirth/early neonatal death and early premature delivery compared with zidovudine/lamivudine, but certainty is low when they are not coprescribed with lopinavir/ritonavir. Other outcomes are likely similar between antiretrovirals.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42017054392.

Efficacy of Antiviral Therapy in HBsAg-Positive Pregnant Women to Reduce Mother-to-Infant Transmission of Hepatitis B Virus

Background and Objectives

Hepatitis B is a major health concern in Asia. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. HBV is transmitted horizontally through blood and blood products and vertically from mother to infant. Perinatal infection is the main route of transmission in regions with high prevalence of hepatitis B surface antigen (HbsAg) carriage, and perinatal transmission leads to high rates of chronic infection. Therefore, it is important to prevent mother-to-child transmission (MTCT) of HBV1. The present study aims at comparing the use of antivirals (lamivudine vs tenofovir) in reducing MTCT.

Materials and Methods

A total of 60 HbsAg-positive pregnant women were enrolled in the prospective study to test the efficacy of antiviral (lamivudine vs tenofovir-category B drug) to reduce mother-to-child transmission and monitor hepatitis B viral status in infant. HbsAg-positive pregnant women aged 18-43 years at gestational age between 28 and 32 weeks were followed up. They were tested for HBsAg, liver function test and HBeAg. In whom HbeAg was positive, HBV viral load was tested. Sixty patients with high viral load (>6 log copies/ml) were recruited in the study. Alternate patients were randomized into two groups. Group A comprised 31 subjects treated with lamivudine 100 mg daily starting from 28 to 32 weeks of gestation (third trimester) and continued to 1 month after delivery. Group B comprised 29 pregnant women who were treated with tenofovir 300 mg daily from 28 to 32 weeks of gestation and continued to 1 month post-partum. The newborn babies were given HBIG within 24 h after delivery and HBV vaccines at 0, 1 and 6 months. HBsAg infectivity was tested in the infant at 1 year after birth.

Results

Antivirals, lamivudine/tenofovir treatment in HBV carrier mothers from 28 weeks of gestation along with active and passive immunization of new born may interrupt MTCT of HBV efficiently. Tenofovir, category B drug, is more effective in preventing transmission of HBV infection to infants (p = 0.004).

Elimination of Perinatal Hepatitis B: Providing the First Vaccine Dose Within 24 Hours of Birth

After the introduction of the hepatitis B vaccine in the United States in 1982, a greater than 90% reduction in new infections was achieved. However, approximately 1000 new cases of perinatal hepatitis B infection are still identified annually in the United States. Prevention of perinatal hepatitis B relies on the proper and timely identification of infants born to mothers who are hepatitis B surface antigen positive and to mothers with unknown status to ensure administration of appropriate postexposure immunoprophylaxis with hepatitis B vaccine and immune globulin. To reduce the incidence of perinatal hepatitis B transmission further, the American Academy of Pediatrics endorses the recommendation of the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention that all newborn infants with a birth weight of greater than or equal to 2000 g receive hepatitis B vaccine by 24 hours of age.

EASL 2017 Clinical Practice Guidelines on the management of hepatitis B virus infection

Hepatitis B virus (HBV) infection remains a global public health problem with changing epidemiology due to several factors including vaccination policies and migration. This Clinical Practice Guideline presents updated recommendations for the optimal management of HBV infection. Chronic HBV infection can be classified into five phases: (I) HBeAg-positive chronic infection, (II) HBeAg-positive chronic hepatitis, (III) HBeAg-negative chronic infection, (IV) HBeAg-negative chronic hepatitis and (V) HBsAg-negative phase. All patients with chronic HBV infection are at increased risk of progression to cirrhosis and hepatocellular carcinoma (HCC), depending on host and viral factors. The main goal of therapy is to improve survival and quality of life by preventing disease progression, and consequently HCC development. The induction of long-term suppression of HBV replication represents the main endpoint of current treatment strategies, while HBsAg loss is an optimal endpoint. The typical indication for treatment requires HBV DNA >2,000IU/ml, elevated ALT and/or at least moderate histological lesions, while all cirrhotic patients with detectable HBV DNA should be treated. Additional indications include the prevention of mother to child transmission in pregnant women with high viremia and prevention of HBV reactivation in patients requiring immunosuppression or chemotherapy. The long-term administration of a potent nucleos(t)ide analogue with high barrier to resistance, i.e., entecavir, tenofovir disoproxil or tenofovir alafenamide, represents the treatment of choice. Pegylated interferon-alfa treatment can also be considered in mild to moderate chronic hepatitis B patients. Combination therapies are not generally recommended. All patients should be monitored for risk of disease progression and HCC. Treated patients should be monitored for therapy response and adherence. HCC remains the major concern for treated chronic hepatitis B patients. Several subgroups of patients with HBV infection require specific focus. Future treatment strategies to achieve 'cure' of disease and new biomarkers are discussed.

Immune balance in Hepatitis B Infection: Present and Future Therapies

Chronic hepatitis B virus (HBV) infection affects millions of people worldwide and about half a million people die every year. India represents the second largest pool of chronic HBV infections with an estimated 40 million chronically infected patients. Persistence or clearance of HBV infection mainly depends upon host immune responses. Chronically infected individuals remain in immune tolerant phase unless HBV flares and leads to the development of chronic active hepatitis or acute-on-chronic liver failure. Strategies based on inhibition of viral replication (nucleoside analogues) or immune modulation (interferons) as monotherapy, or in combination in sequential therapies, are currently being used globally for reducing HBV viral load and mediating HBsAg clearance. However, the immune status and current therapies for promoting sustained virological responses in HBV-infected patients remain suboptimal. Elimination of cccDNA is major challenge for future therapies, and new molecules such as NTCP, Toll-like receptor (TLR)7 agonist (GS9620) and cyclophilin have emerged as potential targets for preventing HBV entry and replication. Other than these, HBV cccDNA elimination is the major target for future therapies.

Low HIV incidence in pregnant and postpartum women receiving a community-based combination HIV prevention intervention in a high HIV incidence setting in South Africa

Background

Young Southern African women have the highest HIV incidence globally. Pregnancy doubles the risk of HIV acquisition further, and maternal HIV acquisition contributes significantly to the paediatric HIV burden. Little data on combination HIV prevention interventions during pregnancy and lactation are available. We measured HIV incidence amongst pregnant and postpartum women receiving a community-based combination HIV prevention intervention in a high HIV incidence setting in South Africa.

Methods

A cohort study that included HIV-uninfected pregnant women was performed. Lay community-based workers provided individualized HIV prevention counselling and performed three-monthly home and clinic-based individual and couples HIV testing. Male partners were referred for circumcision, sexually transmitted infections or HIV treatment as appropriate. Kaplan-Meier analyses and Cox’s regression were used to estimate HIV incidence and factors associated with HIV acquisition.

Results

The 1356 women included (median age 22.5 years) received 5289 HIV tests. Eleven new HIV infections were detected over 828.3 person-years (PY) of follow-up, with an HIV incidence rate of 1.33 infections/100 PY (95% CI: 0.74–2.40). Antenatally, the HIV incidence rate was 1.49 infections/100 PY (95% CI: 0.64–2.93) and postnatally the HIV incidence rate was 1.03 infections/100 PY (95% CI: 0.33–3.19). 53% of male partners received HIV testing and 66% of eligible partners received referral for circumcision. Women within known serodiscordant couples, and women with newly diagnosed HIV-infected partners, adjusted hazard ratio (aHR) = 32.7 (95% CI: 3.8–282.2) and aHR = 126.4 (95% CI: 33.8–472.2) had substantially increased HIV acquisition, respectively. Women with circumcised partners had a reduced risk of incident HIV infection, aHR = 0.22 (95% CI: 0.03–1.86).

Conclusions

Maternal HIV incidence was substantially lower than previous regional studies. Community-based combination HIV prevention interventions may reduce high maternal HIV incidence in resource-poor settings. Expanded roll-out of home-based couples HIV testing and initiating pre-exposure prophylaxis for pregnant women within serodiscordant couples is needed in Southern Africa.

Point-of-care screening for hepatitis B virus infection in pregnant women at an antenatal clinic: A South African experience

BACKGROUND & AIMS

Elimination of HIV and syphilis mother-to-child transmission (MTCT) has received much attention but little consideration has been given to the possibility of elimination of HBV MTCT. In sub-Saharan Africa, HBV vertical transmission continues to be reported and it remains an important public health problem. This study aimed to assess the feasibility of screening pregnant women for HBV using a point-of-care (POC) test and implementing interventions to prevent HBV MTCT.

METHODS

In this observational prospective cohort study, HIV-uninfected pregnant women who consented to testing were screened for HBV using a rapid POC test for HBsAg. Positive results were laboratory-confirmed and tested for HBV DNA and serological markers. Women with viral loads ≥ 20 000 IU/ml received tenofovir (TDF) treatment and all infants received birth-dose HBV vaccine. Two blood samples collected six months apart from HBV-exposed infants within their first year of life were tested for HBV DNA.

RESULTS

Of 144 women who were approached, 134 consented to participating (93% acceptance rate of HBV POC test). Six women tested positive for HBsAg (4.5%; 95% CI 0.99%-8.01%), all confirmed by laboratory testing. Two mothers, M1 and M4, were treated with TDF during their third trimester of pregnancy. Six HBV-exposed infants received the HBV vaccine within 24 hours of birth, of whom two were lost to follow-up and four (including the two born to M1 and M4) had undetectable levels of HBV DNA when tested at the two time points.

CONCLUSION

We found that HBV screening using POC testing fulfilled the criteria considered necessary for implementation. It has acceptable performance, is inexpensive, reliable, and was well accepted by the study participants. Screening pregnant women as part of the HBV MTCT prevention strategy is therefore feasible in a South African clinical setting.

Safety of oral tenofovir disoproxil fumarate-based HIV pre-exposure prophylaxis use in lactating HIV-uninfected women

INTRODUCTION

In settings where HIV is prevalent in heterosexual populations, pregnancy and postpartum breastfeeding periods can be associated with substantial HIV acquisition risk. Pre-exposure prophylaxis (PrEP) with daily oral tenofovir disoproxil fumarate (TDF)/emtricitabine is an attractive HIV prevention option for women who are lactating but data are limited on its safety during the lactation period. Areas covered: We provide a concise synthesis and summary of current evidence on the safety of TDF-based PrEP during breastfeeding. We conducted a review, searching Pubmed database and major PrEP conferences for primary studies with TDF-based PrEP exposure during postpartum breastfeeding. Expert opinion: TDF-based oral PrEP is an effective female-controlled HIV prevention option. There is evidence supporting the safety of TDF use for infant outcomes during breastfeeding in antiretroviral treatment regimens for HIV and hepatitis B virus, and more limited, but consistently safe, data from use of TDF as PrEP. The potential for risk is arguably outweighed for at-risk individuals by HIV prevention benefits, including indirect protection to the infant as a result of preventing HIV in the breastfeeding mother. As PrEP delivery is scaled up in heterosexual populations in high HIV prevalence settings and for at-risk persons in other settings, implementation science studies can provide a framework to increase the accrual of safety, acceptability, and use data related to PrEP during lactation.

Reproductive considerations in the setting of chronic viral illness

Special considerations must be taken when patients with human immunodeficiency virus (HIV), hepatitis B, or hepatitis C desire to become pregnant. Patients with chronic viral illnesses desire to have children at rates similar to the general population, and options are available to decrease both vertical transmission and viral transmission between partners. Preconception counseling or consultation with fertility specialists is imperative in patients with HIV, hepatitis B, and hepatitis C so that reproductive goals can be addressed and optimized. In couples in which one partner has HIV, the use of highly active antiretroviral therapy or preexposure prophylaxis can significantly reduce the risk of transmission between serodiscordant partners. The use of density gradient sperm-washing techniques and intrauterine insemination or in vitro fertilization results in an apparent lack of transmission of HIV between partners when the male partner is HIV-positive. Vertical transmission of HIV from mother to child can be reduced by use of highly active antiretroviral therapy regimens throughout pregnancy or by cesarean delivery in the setting of high maternal viral load. Transmission of hepatitis B between partners can be eliminated by vaccinating the uninfected partner. Vertical transmission from a hepatitis B-infected mother to a child can be reduced by vaccinating neonates with the standard hepatitis B vaccine series as well as hepatitis B immune globulin. Recent data have shown the antiviral medication tenofovir to be an effective way to reduce vertical transmission in the setting of high maternal viral load or the presence of hepatitis B e antigen. There are multiple antiviral medications available to treat chronic hepatitis C, although access to these medications often is limited by cost. Similar to HIV-positive patients, in settings in which the male partner is infected with hepatitis C, density gradient sperm washing can be used before intrauterine insemination or in vitro fertilization to reduce transmission of hepatitis C between partners. No safe and effective method exists to reduce vertical transmission of hepatitis C once a woman becomes pregnant, highlighting the importance of treatment of hepatitis C before pregnancy.

Mechanisms and Prevention of Vertical Transmission in Chronic Viral Hepatitis

Vertical transmission (VT) is the primary route of transmission of viral hepatitis in children. The rate of VT ranges from 1-28% with hepatitis B virus (HBV) and 3-15% with hepatitis C virus (HCV). VT for both viruses can occur during the intrauterine or peripartum period. VT of HBV primarily occurs by intrauterine transmission (IUT). Hepatitis B surface antigen is unable to cross the placenta and, therefore, relies on processes like transplacental leakage, placental infection, cellular transmission by peripheral blood mononuclear cells, and germline transmission. HCV can also infect the fetus by IUT. Both viruses also have the potential for transmission during delivery, when there is increase chance of maternal-fetal blood exposure. HBV and HCV share some common risk factors for VT, including maternal viral load, human immunodeficiency virus co-infection and neonatal sex. Prevention of VT differs greatly between HBV and HCV. There are several alternatives for prevention of HBV VT, including antiviral medications during the third trimester of pregnancy and HBV vaccine, as well as hepatitis B immunoglobulin administration to infants post-partum. In contrast, there are no preventative interventions available for HCV. Despite these differences, the key to prevention with both viruses is screening women prior to and during pregnancy.

Efficacy and safety of tenofovir disoproxil fumarate in preventing vertical transmission of hepatitis B in pregnancies with high viral load

This study was a meta-analysis of the literature on the efficacy and safety of tenofovir disoproxil fumarate (TDF) in preventing vertical transmission of hepatitis B in pregnancies with high viral load. Four observational studies and one randomized controlled trial involving 585 pregnant women and 595 newborns were included in the meta-analysis. TDF was more effective than the placebo in reducing vertical transmission in HBeAg-positive chronic hepatitis B (CHB) pregnancies with high serum HBV-DNA levels (OR = 0.21, 95% CI = 0.07–0.61) at 4–12 months, infant HBV DNA seropositivity at delivery (OR = 0.16, 95% CI = 0.07–0.37), and a severe flair in maternal alanine aminotransferase (ALT) levels (OR = 0.43, 95% CI = 0.19–0.95) during pregnancy. In addition, TDF showed more improvement in HBV DNA suppression at delivery (OR = 254.46, 95% CI = 28.39–2280.79). No significant differences were found in HBeAg seroconversion or ALT normalization; or in rates of cesarean section, emergent cesarean section, postpartum hemorrhage, prematurity, congenital malformations, or infant death. However, TDF induced more drug-related adverse events (OR = 2.33, 95% CI = 1.39–3.89) and elevated creatine kinase (CK) (OR = 9.56, 95% CI = 1.17–78.09) than in controls. The available evidence suggests that TDF is effective and safe in preventing vertical transmission of hepatitis B in pregnancies exhibiting a high viral load.

Is hepatitis B birth dose vaccine needed in Africa?

This commentary describes the need for a birth dose monovalent hepatitis B virus (HBV) vaccine and an effective programme for the prevention of mother-to-child-transmission (MTCT) of HBV in Africa. Current World Health Organization guidelines recommend routine maternal screening for HBV followed by treatment of highly infectious HBV-infected mothers, and HBV birth dose vaccination and the administration of hepatitis B immunoglobulin for HBV-exposed infants as an effective strategy for the prevention of HBV MTCT. None of these practices are currently in place in most parts of Africa. To date, fewer than 10 African countries vaccinate children at birth against HBV. Despite the hurdles associated with implementing this practice, its expansion to the rest of Africa is feasible and crucial to reducing the global number of new HBV infections by 90% by 2030, as targeted by the current Global Health Strategy for the elimination of viral hepatitis.

Mechanism and prediction of HCC development in HBV infection

Chronic hepatitis B virus (HBV) infection remains one of the leading causes of hepatocellular carcinoma (HCC) globally. Over the past few decades, the risk factors of HCC in patients with chronic hepatitis B have been well characterized, and can be divided into host and viral factors. A few groups have also derived and validated HCC prediction scores based on these risk factors. In general, the scores have high negative predictive value in identifying a low risk group who may not need HCC surveillance in the next 3-5 years. The scores have been tested originally in Asian patients, and results on their performance in the Caucasian population are conflicting. Furthermore, new research has identified genetic factors and new virological markers (e.g. hepatitis B surface antigen and core-related antigen levels) for HCC, but they are yet to be applied in routine clinical practice.

Hepatitis B During Pregnancy in Endemic Areas: Screening, Treatment, and Prevention of Mother-to-Child Transmission

The proper management of pregnant women infected with hepatitis B virus (HBV) is necessary to prevent maternal and fetal morbidity and mortality and to protect the baby from HBV infection. In the majority of cases, vertical transmission can be prevented with a universal screening program, HBV vaccine immunoprophylaxis, and administration of hepatitis B immunoglobulin (HBIg) for babies born to mothers with HBV. However, in mothers with a high viral load (>200,000 or >1,000,000 IU/ml, depending on the guideline), the chance of immunoprophylaxis failure remains high. The standard recommendation is to give an antiviral agent during the third trimester in these patients. US FDA pregnancy category B agents such as tenofovir and telbivudine are allowed through all trimesters of pregnancy. Breastfeeding for patients who receive antiviral agents can be allowed after a risk-benefit discussion with the patient.

Systematic review with meta-analysis: the efficacy and safety of tenofovir to prevent mother-to-child transmission of hepatitis B virus

BACKGROUND

Preventing mother to child transmission of chronic hepatitis B infection in the setting of a high maternal viral load is challenging. The idea has emerged from antepartum tenofovir treatment with combination immunoprophylaxis.

AIMS

To demonstrate the efficacy and safety of tenofovir to prevent mother to child transmission of hepatitis B virus.

METHODS

PubMed, EMBASE, and Cochrane databases were searched through August 16, 2016. Comparative trials of second or third trimester tenofovir administration vs. controls for patients with chronic hepatitis B infection and non-comparative case series assessing mother to child transmission rates and evaluating maternal and foetal safety outcomes were included.

RESULTS

Ten studies (one randomised controlled trial, four non-randomised controlled trials and five case series) that enrolled 733 women were included. The pooled results from comparative trials (599 pregnancies) showed that tenofovir significantly reduced the risk of infant hepatitis B surface antigen seropositivity by 77% (odds ratio=0.23, 95% confidence intervals=0.10-0.52, P=.0004) without heterogeneity (I² =0%). In the case series analysis (134 pregnancies), only two cases (1.5%) of mother to child transmission with extremely high maternal viral load and non-compliance to treatment were identified. Maternal and foetal safety parameters including congenital malformation and foetal death were re-assuring.

CONCLUSIONS

For pregnant women with high hepatitis B virus DNA levels, tenofovir administration in the second or third trimester can prevent mother to child transmission when combined with hepatitis B immunoglobulin and the hepatitis B vaccine. Tenofovir is safe and tolerable for both the mother and foetus.

Management of hepatitis B in special populations

Special populations infected with chronic HBV include those with decompensated cirrhosis, coinfections (HIV, HCV, HDV), hemodialysis and renal failure, immunosuppressed including transplant patients, children and women in pregnancy. These populations differ in their natural history and risk for liver-related complications, the indications for anti-HBV therapy as well as the recommendations regarding the HBV drugs used, duration of therapy and anticipated endpoints. Reflecting the special populations with substantive changes in management in recent years, this review focuses on HBV-HIV coinfected patients, immunosuppressed patients at risk for reactivation, liver transplant recipients and pregnant women. Management of women in the context of pregnancy and post-partum requires consideration of risks to mother and fetus/infant, including the risk of mother-to-child transmission. HBV-HIV coinfected patients require initiation of treatment concurrent with their HIV therapy and the HBV drugs used must by selected to minimize HIV and HBV resistance long-term. Increasing recognition of the risk for HBV reactivation with immunosuppressive therapy has led to recommendations to use prophylactic HBV therapy in patients with moderate to high risk of reactivation. Liver transplant recipients with HBV require life-long therapy to prevent or treat HBV infection but with current therapies, graft and patient survival are excellent.

Tenofovir Alafenamide: A Review in Chronic Hepatitis B

Tenofovir alafenamide (AF) [Vemlidy^®], an oral prodrug of tenofovir, was developed to optimize the antiviral potency and clinical safety of the active moiety tenofovir diphosphate (selective reverse transcriptase nucleotide inhibitor). In two identically designed, ongoing, multinational trials in treatment-naive and -experienced adult patients with hepatitis B e antigen (HBeAg)-positive or -negative chronic hepatitis B virus (HBV) infection, once-daily tenofovir AF 25 mg provided effective and sustained viral suppression (120-week analysis), and was generally well tolerated. In the primary 48-week analysis, tenofovir AF was noninferior to once-daily tenofovir disoproxil fumarate (DF) 300 mg in terms of the proportion of patients achieving viral suppression (HBV DNA <29 IU/mL) and was associated with significantly higher alanine aminotransferase (ALT) normalization rates than tenofovir DF based on AASLD criteria (but not central laboratory criteria). In pooled analyses and/or individual trials, ALT normalization rates by AASLD and central laboratory criteria were significantly higher in tenofovir AF than tenofovir DF recipients at most assessed timepoints up to 96 weeks. Given the bone and renal safety concerns associated with long-term tenofovir DF treatment, the more favourable pharmacological profile of tenofovir AF permits a marked reduction in the dosage of this tenofovir prodrug and thereby reduces systemic exposure to tenofovir, potentially improving the bone and renal safety of tenofovir AF versus tenofovir DF. Long-term clinical experience will more definitively establish the relative bone and renal safety of these tenofovir prodrugs. With its potential for an improved safety profile, tenofovir AF is an important emerging first-line option for the treatment of chronic HBV infection in adults and adolescents (aged ≥12 years and with a bodyweight of ≥35 kg).

Recommendations for the treatment of hepatitis B in 2017

The therapeutic goal which is currently unfrequent but realistic in HBV infected patients is sustained HBsAg clearance. It is preceded by the loss or significant suppression of HBV replication and leads to inhibition of the progression of liver fibrosis, normalization of biochemical indicators of liver damage, reduction in the risk of hepatocellular carcinoma, prolongation of survival, prevention of HBV infection in the transplanted organ in post-transplant patients, enhancement of the quality of life, inhibition or reversal of extrahepatic changes associated with HBV infection, and halting of the spread of HBV infections. Recommendations of Polish Group of Experts for HBV for 2017 provide guidelines to assess treatment eligibility, choice of the first-line drug, monitoring and duration of treatment, management of treatment failure as well as therapy of HBV associated cirrhosis or hepatocellular carcinoma. Moreover it contains advice for treatment of HBV infection in children, females planning pregnancy or pregnant. We also included recommendations for pre- and post-exposure prophylaxis, prevention of HBV transmission from mother to infant, after liver transplantation, on immunosuppressive therapy and during HCV treatment.

Immune Tolerant Chronic Hepatitis B: The Unrecognized Risks

Chronic infection with hepatitis B virus (HBV) progresses through multiple phases, including immune tolerant, immune active, immune control, and, in a subset of patients who achieve immune control, reactivation. The first, the immune tolerant phase, is considered to be prolonged in duration but essentially benign in nature, lacking long-term consequences, and thus not recommended for antiviral therapy. This review challenges the notion that the immune tolerant phase is truly benign and considers the possibility that events during this phase may contribute significantly to cirrhosis, hepatocellular carcinoma (HCC), and the premature death of 25% of HBV carriers worldwide. Thus, earlier treatment than recommended by current guidelines should be considered. Low therapeutic coverage exacerbated by restrictive treatment guidelines may facilitate disease progression in many patients but also increase the risk of neonatal and horizontal transmission from untreated mothers to their children. While a prophylactic vaccine exists, there are many areas worldwide where the treatment of adults and the delivery of an effective vaccination course to newborns present difficult challenges.

Early childhood transmission of hepatitis B prior to the first hepatitis B vaccine dose is rare among babies born to HIV-infected and non-HIV infected mothers in Gulu, Uganda

BACKGROUND

Hepatitis B (HBV) in sub-Saharan Africa is believed to be horizontally acquired. However, because of the high HBV prevalence in northern Uganda, no hepatitis B vaccination at birth and no access to HBV immunoglobulin, we hypothesize that vertical transmission also could also play an important role. We therefore investigated the incidence of HBV among babies presenting for their first HBV vaccine dose in Gulu, Uganda.

METHODS

We recruited mothers and their babies (at least 6-week old) presenting for their postnatal care and first HBV vaccine dose respectively. Socio-demographic and risk factors for HBV transmission were recorded. Mothers were tested for Hepatitis B core antibody (anti-HBc-IgG) and hepatitis B surface antigen (HBsAg). HBsAg-positive sera were tested for hepatitis B e antigen (HBeAg) and HBV viral load (HBVDNA). Babies were tested for HBsAg at presentation and at the last immunization visit. A sample of HBsAg-negative babies were tested for HBVDNA. Incident HBV infection was defined by either a positive HBsAg or HBVDNA test. Chi-square or fisher's exact tests were utilized to investigate associations and t-tests or Wilcoxon rank-sum test for continuous differences.

RESULTS

We recruited 612 mothers, median age 23years (IQR 20-28). 53 (8.7%) were HBsAg-positive and 339 (61.5%) were anti-HBc-IgG-positive. Ten (18.9%) of the HBsAg-positive mothers were HBeAg-positive. Median HBVDNA levels of HBV-infected mothers was 5.7log (IQR 4.6-7.0) IU/mL with 9 (17.6%) having levels≥10⁵IU/mL. Eighty (13.3%) mothers were HIV-infected of whom 9 (11.5%) were co-infected with HBV. No baby tested HBsAg or HBVDNA positive.

CONCLUSION

Vertical transmission does not seem to contribute substantially to the high HBV endemicity in northern Uganda. The current practice of administering the first HBV vaccine to babies in Uganda at six weeks of age may be adequate in control of HBV transmission.

Telbivudine treatment started in early and middle pregnancy completely blocks HBV vertical transmission

Background

To evaluate the efficacy and safety of treating HBV-positive mothers with telbivudine in early and middle pregnancy to prevent mother-to-infant HBV transmission.

Methods

The subject population comprised pregnant women with chronic hepatitis B (CHB; n = 188) from January 2013 to June 2015, with HBV DNA ≥1.0 × 10⁷copies/mL and increased alanine aminotransferase levels. Groups A (n = 62) and B (n = 61) were treated with telbivudine starting at 12 weeks or 20–28 weeks after gestation, respectively. Telbivudine was discontinued at postpartum 12 weeks. Group C (n = 65) received no antiviral. All infants were vaccinated with hepatitis B immunoglobulin (200 IU) and HBV vaccine (20 with hepatitis B The maternal HBV DNA levels of the groups were compared. Mother-to-infant transmission of HBV was indicated by the presence of HBsAg in infants 7 months after birth.

Results

Before treatment, the HBV DNA levels of the 3 groups were similar. Before delivery and 12 weeks after delivery, the HBV DNA levels of groups A and B were similar, but both were significantly lower than that of group C (P < 0.01, all). No infants in groups A and B were HBsAg-positive, but the infection rate of group C was 18.4% (P < 0.01). The HBV infection rate of infants was positively associated with the HBV DNA levels of the pregnant mothers.

Conclusion

Administration of telbivudine to HBV-infected mothers, started during early and middle pregnancy, completely blocked mother-to-infant HBV transmission.

Trial registration

The study was registered retrospectively on Janurary 25 in 2016 at Chinese Clinical Trial Registry (ChiCTR-OPC-16007899).

Elimination of Hepatitis B: Is It a Mission Possible?

Chronic hepatitis B virus (HBV) infection is a global public health issue. Although the disease cannot be cured effectively, disease management has been improved over the past decade. The introduction of potent nucleos(t)ide analogues (NAs) to suppress viral replication represented a giant leap in the control of this disease. It has been shown that tenofovir treatment, a potent NA, complements current immunoprophylaxis to diminish mother-to-infant transmission in pregnant women with a high viral load. For patients with chronic HBV infection, quantitative hepatitis B surface antigen is a useful tool to define inactive carriers and to guide antiviral therapy. Quantification of HBV mutants is also useful in predicting long-term outcomes more precisely than ever. The next challenge is how to achieve an HBV cure; although immunotherapy is a promising strategy, the current results from two clinical trials using therapeutic vaccines to induce HBV-specific immune response in patients with chronic HBV infection are disappointing. In the coming years, we are expecting to see a combination of therapeutic agents with various modes of action to complete the mission of HBV elimination.

Prospective interventional study of tenofovir in pregnancy to prevent vertical transmission of hepatitis B in highly viremic women

BACKGROUND

The risk of vertical transmission of hepatitis B virus (HBV) increases as maternal HBV DNA increase, despite serovaccination to newborns.

METHODS

From 1 July 2012 to 1 January 2016, all pregnant women in Lariboisiere Hospital, Paris, France, with HBV DNA of 5 log10 IU/ml and above were administered tenofovir from week 28 of pregnancy until delivery. HBV DNA was measured at months 1, 2 of tenofovir and at delivery. The newborns were serovaccinated, tested for hepatitis B surface antigen, hepatitis B core antibody (HBcAb)±HBV DNA, and hepatitis B surface antibody (HBsAb) when aged 9 months, and then 24 months. This study was registered in http://www.ClinicalTrials.gov (NCT02039362).

RESULTS

Thirty-one women gave birth to 37 newborns. Maternal HBV DNA at baseline was 8.23 log10 IU/ml and above in 12 pregnancies. The mean (median) HBV DNA were 4.4±1.2 (4.8), 3.3±1.7 (3.8), and 2.1±1.9 (2.0) log10 IU/ml at months 1, 2 of tenofovir and at delivery, respectively. Twenty-seven newborns were followed up: none of the 19 children aged 9 months or older was positive for hepatitis B surface antigen when aged 9 months; 14 children tested positive for HBcAb (probably transferred maternal antibodies, not found when aged 24 months) and for HBsAb without HBV DNA. Four of the 19 children showed HBsAb without HBcAb, the last being doubtful for HBcAb and HBsAb without HBV DNA. Eight newborns aged less than 9 months were not tested.

CONCLUSION

Tenofovir from week 28 of pregnancy to highly viremic HBV women plus serovaccination to newborns could prevent chronic and past infection.

Tenofovir disoproxil fumarate safety for women and their infants during pregnancy and breastfeeding

OBJECTIVES

Pregnant/lactating women in some sub-Saharan Africa settings are at substantial risk of HIV acquisition and could benefit from preexposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF), but safety data in pregnancy/lactation are limited.

DESIGN

Systematic data review through August 2016.

METHODS

We reviewed research reports/conference abstracts with maternal/child adverse outcome data in HIV-infected and HIV-uninfected pregnant/lactating women receiving TDF alone or in combination with other drugs compared with non-TDF regimens.

RESULTS

In total, 26 articles in HIV-infected and seven in HIV-uninfected women were identified. No statistically significant differences were observed between TDF and comparison non-TDF regimens in pregnancy incidence, stillbirth/pregnancy loss, preterm delivery less than 37 weeks, low birth weight <2500/<1500 g, small for gestational age, birth defects, or infant (>14 days) or maternal mortality. One study reported significantly higher very preterm delivery (<34 weeks) and neonatal mortality with TDF versus non-TDF antiretroviral therapy (ART), but no significant difference between TDF ART and zidovudine/single-dose nevirapine. Most studies report normal infant linear growth; one study showed slightly lower, and one higher 1-year length-for-age z-score in TDF ART-exposed infants. No significant differences were reported in abnormal laboratory values or bone markers between TDF and non-TDF-exposed infants in four studies. Lower maternal bone mineral density was observed at 74 weeks postpartum in breastfeeding women on TDF ART compared with no ART in one study.

CONCLUSION

Given available safety data, there does not appear to be a safety-related rationale for prohibiting PrEP during pregnancy/lactation or for discontinuing PrEP in HIV-uninfected women receiving PrEP who become pregnant and are at continuing risk of HIV acquisition.

Adolescent booster with hepatitis B virus vaccines decreases HBV infection in high-risk adults

BACKGROUND

Neutralizing antibodies (anti-HBs) after immunization with hepatitis B virus (HBV) vaccines against HBV surface antigen (HBsAg) wane after 10-15years. We analyzed the effect of an adolescent booster given to vaccination-protected children born to mothers with different HBsAg-carrying status against HBV infection in their mature adulthood.

METHODS

A total of 9793 individuals, who were HBsAg-negative at childhood (baseline) and donated blood samples, both during childhood and adulthood, from the vaccination group in "Qidong Hepatitis B Intervention Study", were enrolled. Among them 7414 received a one-dose, 10μg-recombinant HBV vaccine booster at 10-14years of age. At endpoint (23-28years of age), we determined the HBV serological markers and quantified their serum HBV-DNA in each of the chronic HBV-infected adults.

RESULTS

Fifty-seven adults were identified as chronic HBV infection, indicated by HBsAg(+)&anti-HBc(+) for more than 6months. The individuals who were born to HBsAg-positive mothers (high-risk adults) had significantly increased risk of developing chronic HBV infections in adulthood compared with those who were born to HBsAg-negative mothers; the adjusted odds ratio (OR) was 12.56, 95%CI:7.14-22.08. The seronegative status of anti-HBs at 10-11years of age significantly increased the risk of HBV infections among the high-risk adults. When HBsAg(-)&anti-HBc(+) children who were born to HBsAg-positive mothers 70% of them remained as the status and 10% of them developed HBsAg(+)&anti-HBc(+). While when they were born to HBsAg-negative mothers 1.05% HBsAg(-)&anti-HBc(+) children developed HBsAg(+)&anti-HBc(+) and 24.74% of them remained as the status in 12-18years. One dose of adolescent booster showed significant protection on high-risk adults from chronic HBV infection; P for trend was 0.015.

CONCLUSIONS

Maternal HBsAg-positive status was an independent risk factor for vaccination-protected children to develop HBV breakthrough infection in adulthood. Adolescent boosters might be appropriate for high-risk individuals who were born to HBsAg-positive mothers when their serum anti-HBs<10mIU/ml.

Telbivudine therapy for chronic hepatitis B: A journey to identify super-responders and to optimize treatment using the roadmap model

Hepatitis B virus (HBV) infection is one of the most serious health problems worldwide with a high risk for cirrhosis and liver cancer. Several antiviral agents have been approved for the treatment of chronic hepatitis B, leading to a rapid reduction in HBV DNA and normalization of serum alanine aminotransferase levels. Telbivudine, a potent inhibitor of HBV replication, has been shown to be well tolerated. Because of the emergence of drug resistance, optimization strategies for telbivudine therapy have been shown to improve patient responses. Optimal baseline characteristics in so-called super-responders have been used to predict the virological response. Baseline HBV DNA levels < 9 log₁₀ copies/mL (2 × 10⁸  IU/mL) or alanine aminotransferase levels of more than or equal to twofold the upper limit of normal in HBeAg-positive patients and HBV DNA < 7 log₁₀ copies/mL (2 × 10⁶  IU/mL) in HBeAg-negative patients were strong predictors for virological response. In addition, the roadmap model, based on early virological response at week 24 of therapy, is considered as a powerful tool to identify patients at risk of treatment failure (HBV DNA ≥ 300 copies/mL, i.e. 60 IU/mL) and to reduce the risk of antiviral resistance. When considering pre-treatment characteristics and on-treatment responses, telbivudine may provide physicians with a wide choice of options to effectively treat patients with chronic hepatitis B, especially those with or at risk of renal impairment, or women of childbearing age.

Challenges in warranting access to prophylaxis and therapy for hepatitis B virus infection

Despite an available vaccine and efficient treatment for hepatitis B virus (HBV) infection, chronic HBV infection still remains a major global threat, and one of the top 20 causes of human mortality worldwide. One of the major challenges in controlling HBV infection is the high number of undiagnosed chronic carriers and the lack of access to prophylaxis and treatment in several parts of the world. We discuss relevant barriers that need to be overcome to achieve global control of HBV infection and make eradication possible. Most important, vaccination must be scaled-up to lower the risk of vertical transmission and decrease the number of new infections, and comprehensive screening programs must be linked to care to obtain a better rate of diagnosis and treatment. This can probably only be achieved if sustainable funding is available. We therefore emphasize the importance of making the management of viral hepatitis a global health priority.

New perspectives of biomarkers for the management of chronic hepatitis B

With recent advances in molecular and genomic investigations, the impact of hepatitis B viral and host factors on the progression of chronic HBV infection has been explored. For viral factors, hepatitis B viral load is a strong predictor for liver disease progression. Hepatitis B viral kinetics appear to be important for successful anti-viral therapy. Serum HBsAg level serves as a complementary marker to viral load for the prediction of HBV-related adverse outcomes in patients with low viral load. In those with low viral load, high serum HBsAg level is associated with higher risks of cirrhosis and HCC. Hepatitis B core-related antigen (HBcrAg) induces host immune responses, and the reduction of the HBcrAg level as well as the increment of total anti-HBc level are significantly associated with favorable outcomes. HBV genotypes (genotype C/D) and mutants (basal core promoter and deletion mutation in pre-S genes) are well known viral genetic markers to predict disease progression. For host factors, serum inflammatory biomarkers have been developed to evaluate the HBV-associated hepatic necroinflammation and fibrosis. Host single nucleotide polymorphism on sodium taurocholate cotransporting polypeptide (NTCP, an HBV entry receptor) may be associated with a decreased risk for cirrhosis and HCC. In conclusion, patients with chronic hepatitis B should be evaluated with relevant viral and host markers to identify those who are at a higher risk of liver disease progression and then receive timely antiviral therapy.

Hepatitis B Virus (HBV) Load Response to 2 Antiviral Regimens, Tenofovir/Lamivudine and Lamivudine, in HIV/ HBV-Coinfected Pregnant Women in Guangxi, China: The Tenofovir in Pregnancy (TiP) Study

BACKGROUND

 There is limited information on antiviral therapy for hepatitis B virus (HBV) infection among pregnant women coinfected with human immunodeficiency virus (HIV) and HBV.

METHODS

 A phase 2 randomized, controlled trial of a regimen containing tenofovir (TDF)/lamivudine (3TC) and a regimen containing 3TC in HIV/HBV-coinfected pregnant women in China. The HBV virological response was compared in study arms.

RESULTS

 The median decline in the HBV DNA level was 2.60 log10 copies/mL in the TDF/3TC arm and 2.24 log10 copies/mL in the 3TC arm (P = .41). All women achieved HBV DNA levels of <6 log10 copies/mL at delivery.

CONCLUSIONS

 Initiation of either regimen led to achievement of HBV DNA levels below the threshold associated with perinatal HBV transmission.

CLINICAL TRIALS REGISTRATION

 NCT01125696.

Indications for antiviral therapy for chronic hepatitis B in pregnant mothers

The use of antiviral therapy for chronic hepatitis B virus (HBV) infection in the setting of pregnancy needs to be individualised based on limited data. We report a case of a 34-year-old Korean-American woman with a history of pregnancy with emergent caesarean section due to prolonged labour in the setting of HBV e-antigen (HBeAg) positive chronic HBV with a pretreatment baseline HBV DNA level of 110000 000 million copies per mL. Her first delivery was complicated by mother-to-child transmission (MTCT) of HBV infection to her daughter despite standard active and passive immunoprophylaxis. Our case report highlights an important clinical decision-making step regarding the timing of antiviral therapy in the management of chronic HBV in pregnant women with high risk of MTCT.

Screening and management of viral hepatitis and hepatocellular carcinoma in Mongolia: results from a survey of Mongolian physicians from all major provinces of Mongolia

Background

According to Globocan, Mongolia has the highest worldwide hepatocellular carcinoma (HCC) incidence (78.1/100 000, 3.5× higher than China).

Aims and methods

We conducted an anonymous survey of physicians from major provinces who attended an educational liver symposium, analysing their demography, practice, knowledge, perceptions and proposed solutions. Multivariate logistic regression was used to estimate OR relating demography and practice factors with higher provider knowledge and improvement.

Results

Of the 121 attendees, 44–95 (36–79%) responded to each question. Most were female (87%), young (79% age <50), subspecialists (81%), university-affiliated (74%), and practised in urban areas (61%). The mean pretest and post-test scores per physician were 60.4±20.4 and 65.6±21.3, with no observed significant predictors for baseline knowledge or improvement. Most (>80%) noted that <50% of patients who need hepatitis or HCC screening receive it. The main perceived barriers to screening were inability to pay for tests, lack of guidelines and poor patient awareness. Hepatitis treatment rates were low; 83% treated hepatitis C virus in <10 patients in the past year, and 86% treated hepatitis B virus in <10 patients/month. Treatment barriers were multifactorial, with cost as a principal barrier. Proposed solutions were universal screening policies (46%), removal of financial barriers (28%) and provider education (20%).

Conclusions

Physicians from major regions of Mongolia noted low screening for viral hepatitis, even lower treatment rates, financial barriers and the need for increased educational efforts. We advocate broad-based medical education tailored to local needs and based on needs assessment and outcome measurements.

Treatment of chronic hepatitis B with tenofovir

Tenofovir (TDF) is a potent hepatitis B virus (HBV) inhibitor with a high barrier to drug resistance, and it has been recommended as one of the first-line drugs to treat chronic hepatitis B (CHB). This paper reviews the recent advances in the treatment of CHB with TDF, especially in terms of its efficacy as first-line and second-line antiviral therapies as well as its role in the prevention of mother-to-child HBV transmission.

Systematic review with meta-analysis: the risk of mother-to-child transmission of hepatitis B virus infection in sub-Saharan Africa

BACKGROUND

The risk of mother-to-child transmission of hepatitis B virus (HBV) has been quoted as 70-90% among women positive for hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), and 5-30% among HBsAg-positive HBeAg-negative women. These risks are derived from Asia; little is known about sub-Saharan Africa.

AIM

To determine the risk of mother-to-child transmission in sub-Saharan Africa, according to maternal HBeAg and type of prophylaxis.

METHODS

We searched Medline, Global Health, Embase, African Journals Online and African Index Medicus. We included observational or interventional studies that enrolled infants of HBV-infected women, and that tested for HBsAg or HBV DNA between 3 and 12 months of age.

RESULTS

Fifteen articles from 11 African countries were included. Among HBeAg-positive women, the pooled risk was 38.3% (95% CI: 7.0-74.4%) without prophylaxis, which was significantly lower than the lower bound of 70-90% risk in the literature (P = 0.007). Among HBeAg-negative women, the pooled risk was 4.8% (95% CI: 0.1-13.3%) without prophylaxis, which lays within the lower range of the 5-30% risk in Asia. By extrapolating the pooled transmission risks to the number of births to infectious mothers, an estimated 1% of newborns (n = 367 250) are annually infected with HBV at birth in sub-Saharan Africa.

CONCLUSIONS

Compared to Asia, the risk of mother-to-child transmission is low in sub-Saharan Africa. However, the annual number of infants perinatally infected with HBV is twice the number of incident paediatric HIV infections in sub-Saharan Africa (n = 190 000). This highlights the importance of preventing mother-to-child transmission of HBV in sub-Saharan Africa, which has been long neglected.