Epidemiological patterns of hepatitis B virus (HBV) in highly endemic areas

Hepatitis B Virus Prevalence and Transmission in the Households of Pregnant Women in Kinshasa, Democratic Republic of Congo

Background

The World Health Organization Africa region has high regional hepatitis B virus (HBV) prevalence, and evidence suggests more frequent horizontal HBV transmission than other regions. Context-specific epidemiological studies are needed to inform additional HBV prevention measures.

Methods

In the cross-sectional Horizontal and Vertical Transmission of Hepatitis B (HOVER-HBV) study, we introduced HBV surface antigen (HBsAg) screening alongside existing HIV screening as part of routine antenatal care in high-volume maternity clinics in Kinshasa, Democratic Republic of Congo. We recruited households of pregnant women ("index mothers") who were HBsAg-positive and HBsAg-negative, defining households as index-positive and index-negative, respectively. Household members underwent HBsAg testing and an epidemiological survey. We evaluated HBsAg prevalence and potential transmission correlates.

Results

We enrolled 1006 participants from 200 households (100 index-positive, 100 index-negative) across Kinshasa. HBsAg-positivity prevalence was more than twice as high in index-positive households (5.0% [95% confidence interval {CI}, 2.8%-7.1%]) as in index-negative households (1.9% [95% CI, .6%-3.2%]). HBsAg-positivity prevalence was 3.3 (95% CI, .9-11.8) times as high among direct offspring in index-positive versus index-negative households. Factors associated with HBsAg positivity included older age, marriage, and having multiple recent partners or any new sexual partners among index mothers; and older age, lower household wealth, sharing nail clippers, and using street salons among offspring in index-positive households.

Conclusions

Vertical and horizontal HBV transmission within households is ongoing in Kinshasa. Factors associated with infection reveal opportunities for HBV prevention efforts, including perinatal prevention, protection during sexual contact, and sanitation of shared personal items.

Childhood immunization uptake determinants in Kinshasa, Democratic Republic of the Congo: ordered regressions to assess timely infant vaccines administered at birth and 6-weeks

BACKGROUND

Despite global efforts to reduce preventable childhood illness by distributing infant vaccines, immunization coverage in sub-Saharan African settings remains low. Further, timely administration of vaccines at birth-tuberculosis (Bacille Calmette-Guérin [BCG]) and polio (OPV0)-remains inconsistent. As countries such as Democratic Republic of the Congo (DRC) prepare to add yet another birth-dose vaccine to their immunization schedule, this study aims to improve current and future birth-dose immunization coverage by understanding the determinants of infants receiving vaccinations within the national timeframe.

METHODS

The study used two ordered regression models to assess barriers to timely BCG and first round of the hepatitis B (HepB3) immunization series across multiple time points using the Andersen Behavioral Model to conceptualize determinants at various levels. The assessment leveraged survey data collected during a continuous quality improvement study (NCT03048669) conducted in 105 maternity centers throughout Kinshasa Province, DRC. The final sample included 2398 (BCG analysis) and 2268 (HepB3 analysis) women-infant dyads living with HIV.

RESULTS

Between 2016 and 2020, 1981 infants (82.6%) received the BCG vaccine, and 1551 (68.4%) received the first dose of HepB3 vaccine. Of those who received the BCG vaccine, 26.3%, 43.5%, and 12.8% received BCG within 24 h, between one and seven days, and between one and 14 weeks, respectively. Of infants who received the HepB3 vaccine, 22.4% received it within six weeks, and 46% between six and 14 weeks of life. Many factors were positively associated with BCG uptake, including higher maternal education, household wealth, higher facility general readiness score, and religious-affiliated facility ownership. The factors influencing HepB3 uptake included older maternal age, higher education level, household wealth, transport by taxi to a facility, higher facility general and immunization readiness scores, and religious-affiliated facility ownership.

CONCLUSIONS

This study demonstrated that the study participants' uptake of vaccines was consistent with the country average, but not in a timely manner. Various factors were associated with timely uptake of BCG and HepB3 vaccines. These findings suggest that investment to strengthen the vaccine delivery system might improve timely vaccine uptake and equity in vaccine coverage.

Hepatitis B virus prevalence and transmission in the households of pregnant women in Kinshasa, Democratic Republic of Congo

Background

Despite routine infant vaccination and blood donor screening, the Democratic Republic of Congo (DRC) has high hepatitis B virus (HBV) prevalence compared to the United States and Europe. Through the cross-sectional Horizontal and Vertical Transmission of Hepatitis B (HOVER-HBV) study, we characterized household prevalence in DRC's capital, Kinshasa, to inform additional prevention efforts.

Methods

We introduced HBV surface antigen (HBsAg) screening alongside existing HIV screening as part of routine antenatal care (ANC) in high-volume maternity clinics in Kinshasa. We recruited households of pregnant women who were HBsAg-positive and HBsAg-negative, defining households as "exposed" and "unexposed," respectively. Household members underwent HBsAg testing and an epidemiological survey. We evaluated HBsAg prevalence and potential transmission correlates.

Results

We enrolled 1,006 participants from 200 households (100 exposed, 100 unexposed) across Kinshasa. HBsAg prevalence was more than twice as high in exposed households (5.0%; 95% CI: 2.8%-7.1%) as in unexposed households (1.9%; 0.6%-3.2%). Exposed direct offspring had 3.3 (0.9, 11.8) times the prevalence of unexposed direct offspring. Factors associated with HBsAg-positivity included older age, marriage, and having multiple recent partners or any new sexual partners among index mothers; and older age, lower household wealth, sharing nail clippers, and using street salons among exposed offspring.

Conclusions

Vertical and horizontal HBV transmission within households is ongoing in Kinshasa. Factors associated with infection reveal opportunities for HBV prevention efforts, including perinatal prevention, protection during sexual contact, and sanitation of shared personal items.

Hepatitis B prevention and treatment needs in women in Senegal (ANRS 12356 AmBASS survey)

BACKGROUND

Although mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is prevalent in West Africa, epidemiological data on HBV infection in women remain scarce. We studied i) hepatitis B surface antigen (HBsAg) prevalence and its correlates, ii) HBV screening history and serological status awareness, iii) MTCT risk and treatment needs in Senegalese women.

METHODS

A cross-sectional population-based serosurvey for HBsAg positivity was conducted in 2018-2019 in the rural area of Niakhar (Fatick region, Senegal). Participants were offered home-based HBV screening and answered face-to-face questionnaires. HBsAg-positive participants underwent clinical and biological assessments. Data were weighted and calibrated to be representative of the area's population. Logistic regression models helped identify factors associated with HBsAg-positivity in adult women (> 15 years old).

RESULTS

HBsAg prevalence in adult women was 9.2% [95% confidence interval: 7.0-11.4]. Factors associated with HBsAg-positivity were being 15-49 years old (ref: ≥ 50), living in a household with > 2 other HBsAg-positive members, and knowing someone with liver disease. Only 1.6% of women had already been tested for HBV; no one who tested HBsAg positive was already aware of their serological status. In women 15-49 years old, 5% risked MTCT and none were eligible for long-term antiviral treatment.

CONCLUSIONS

Adult women have a high HBsAg prevalence but a low MTCT risk. Low rates of HBV screening and serological status awareness argue for the adoption of systematic screening during pregnancy using free and rapid diagnostic tests. Additionally, screening household members of HBsAg-positive women may greatly improve the cascade of care in rural Senegal.

TRIAL REGISTRATION

ClinicalTrials.gov identifier (NCT number): NCT03215732.

Hepatitis B Core Antibody Level: A Surrogate Marker for Host Antiviral Immunity in Chronic Hepatitis B Virus Infections

The hepatitis B virus core protein (HBcAg) is a highly immunogenic particulate antigen. Nearly all patients with persistent or resolved hepatitis B virus (HBV) infection show seropositivity for hepatitis B core antibody (anti-HBc), which appears in the early stage of infection and is mostly present for life. Traditionally, the anti-HBc is regarded as an evidential serological marker of HBV infections. In the last ten years, several studies revealed the predictive value of quantitative anti-HBc (qAnti-HBc) level in the treatment response and clinical outcome of chronic HBV infections, implying new insights into this classic marker. Overall, qAnti-HBc should be regarded as an indicator of the host's immune response specific to HBV, which correlates with HBV-related hepatitis activity and liver pathology. This review summarized the latest understanding of the clinical values of qAnti-HBc for differentiating the CHB phase, predicting treatment response, and providing disease prognosis. Moreover, we also discussed the possible mechanism of qAnti-HBc regulation during different courses of HBV infection.

Risk of early horizontal transmission of hepatitis B virus in children of uninfected mothers in sub-Saharan Africa: a systematic review and meta-analysis

BACKGROUND

Sub-Saharan Africa is highly endemic for hepatitis B virus (HBV); historically, most people were exposed during childhood through vertical or horizontal transmission. Although all African countries now provide a three-dose infant hepatitis B vaccination starting at age 6-8 weeks, only a third of African countries have introduced birth dose (HepB-BD) vaccine. Adding HepB-BD is fundamental to prevent vertical transmission, but its effectiveness in preventing horizontal transmission, compared with the three-dose infant vaccination alone, is unknown. We aimed to estimate the risk of early horizontal transmission in children of hepatitis B surface antigen (HBsAg)-negative mothers in sub-Saharan Africa stratified according to the vaccination schedule.

METHODS

In this systematic review and meta-analysis we searched MEDLINE, Global Health, Embase, African Index Medicus and African Journals Online from their inception to Oct 24, 2022, for studies reporting HBsAg or HBV DNA, or both, in children (aged 0-5 years) of HBsAg-negative mothers. We excluded studies if children were only tested at birth. Two reviewers independently screened the titles and abstracts of all articles and data were extracted using a standardised pre-piloted data extraction sheet, and authors were contacted if any important information was missing. The primary outcome was the risk of HBV infection in children of HBsAg-negative mothers, stratified by vaccination schedule (no vaccination, first dose at 6-8 weeks, or first dose at birth). We pooled the child risks of HBsAg or HBV DNA-positivity from the age of 0 years to 5 years via a random-effect meta-analysis using a generalised linear mixed model. The study was registered on PROSPERO, CRD42021236203.

FINDINGS

Of 8856 articles identified, 27 studies evaluating 10 003 children of HBsAg-negative mothers were included. The pooled risks of infection were 6·16% (95% CI 3·05-12·04; 155/1407) in the no vaccination group, 0·21% (0·04-1·15; 10/3425) in children who received their first dose at 6-8 weeks, and 0·05% (0·00-1·32; 3/2902) in children who received their first dose at birth. The difference was not statistically significant in children who received their first dose at 6-8 weeks and children who received their first dose at birth after adjusting for the study period, region, and maternal HIV status (test of moderators p=0·37).

INTERPRETATION

In children of HBsAg-negative mothers, the risk of infection might be minimal even with the vaccination starting at 6-8 weeks, without clear additional benefit from HepB-BD. When births take place at home and timely administration of HepB-BD is challenging, antenatal HBsAg screening and selective HepB-BD might allow efficient allocation of resources to mother and child pairs at high risk compared with universal HepB-BD.

FUNDING

None.

TRANSLATION

For the French translation of the abstract see Supplementary Materials section.

Vertical Transmission of Hepatitis B Virus-An Update

Hepatitis B virus (HBV) infection is a major public health problem in the world. Approximately 296 million people are chronically infected. In endemic areas, vertical transmission is a common route of transmission. There are several strategies for the prevention of HBV vertical transmission, such as antiviral treatment during the third trimester of pregnancy and immunoprophylaxis to newborns that includes the administration of hepatitis B immune globulin (HBIG) and an HBV vaccine. Despite this, immunoprophylaxis failure can occur in up to 30% of infants born to HBeAg-positive mothers and/or with high viral load. Therefore, management and prevention of HBV vertical transmission is of paramount significance. In this article, we provided a review of the epidemiology, mechanisms of pathogenesis and risk factors of vertical transmission, as well as the strategies implemented to prevent the infection.

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

INTRODUCTION

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.

MATERIAL AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

The impact of the COVID-19 pandemic on hepatitis B virus vaccination and transmission among men who have sex with men: a mathematical modelling study

Background

Methods

Results

Conclusions

Hepatitis B in Senegal: A Successful Infant Vaccination Program but Urgent Need to Scale Up Screening and Treatment (ANRS 12356 AmBASS survey)

Senegal introduced the infant hepatitis B virus (HBV) vaccination in 2004 and recently committed to eliminating hepatitis B by 2030. Updated epidemiological data are needed to provide information on the progress being made and to develop new interventions. We estimated the prevalence of hepatitis B surface antigen (HBsAg) in children and adults living in rural Senegal and assessed hepatitis B treatment eligibility. A cross-sectional population-based serosurvey of HBsAg was conducted in 2018-2019 in a large sample (n = 3,118) of residents living in the Niakhar area (Fatick region, Senegal). Individuals positive for HBsAg subsequently underwent clinical and biological assessments. Data were weighted for age and sex and calibrated to be representative of the area's population. Among the 3,118 participants, 206 were HBsAg positive (prevalence, 6.9%; 95% confidence interval [CI], 5.6-8.1). Prevalence varied markedly according to age group in individuals aged 0-4, 5-14, 15-34, and ≥35 years as follows: 0.0% (95% CI, 0.00-0.01); 1.5% (95% CI, 0.0-2.3); 12.4% (95% CI, 9.1-15.6); and 8.8% (95% CI, 6.1-11.5), respectively. Of those subsequently assessed, 50.9% (95% CI, 41.8-60.0) had active HBV infection; 4 (2.9%; 95% CI, 0.9-9.4) were eligible for hepatitis B treatment. Conclusion: In this first population-based serosurvey targeting children and adults in rural Senegal, HBsAg prevalence was very low in the former, meeting the World Health Organization's (WHO) < 1% HBsAg 2020 target; however, it was high in young adults (15-34 years old) born before the HBV vaccine was introduced in 2004. To reach national and WHO hepatitis elimination goals, general population testing (particularly for adolescents and young adults), care, and treatment scale-up need to be implemented.

Assessing the impact of the routine childhood hepatitis B immunization program and the need for hepatitis B vaccine birth dose in Sierra Leone, 2018

Sierra Leone is highly endemic for hepatitis B virus (HBV) infection and thus recommends three doses of hepatitis B vaccine (HepB3) from 6 weeks of age but does not recommend a birth dose (HepB-BD) to prevent mother-to-child transmission (MTCT). We evaluated impact of the existing HepB3 schedule and risk for MTCT of HBV. We conducted a community-based serosurvey among 4-30-month-olds, their mothers, and 5-9-year-olds in three districts in Sierra Leone. Participants had an HBV surface antigen (HBsAg) rapid test; all HBsAg-positive and one HBsAg-negative mother per cluster were tested for HBV markers. We collected children's HepB3 vaccination history. Among 1889 children aged 4-30 months, HepB3 coverage was 85% and 20 (1·3% [95% CI 0·8-2·0]) were HBsAg-positive, of whom 70% had received HepB3. Among 2025 children aged 5-9 years, HepB3 coverage was 77% and 32 (1·6% [1·1-2·3]) were HBsAg-positive, of whom 56% had received HepB3. Of 1776 mothers, 169 (9·8% [8·1-11·7]) were HBsAg-positive. HBsAg prevalence was 5·9% among children of HBsAg-positive mothers compared to 0·7% among children of HBsAg-negative mothers (adjusted OR = 10·6 [2·8-40·8]). HBsAg positivity in children was associated with maternal HBsAg (p = 0·026), HBV e antigen (p < 0·001), and HBV DNA levels ≥ 200 000 IU/mL (p < 0·001). HBsAg prevalence was lower among children than mothers, for whom HepB was not available, suggesting routine infant HepB vaccination has lowered HBV burden. Since HBsAg positivity in children was strongly associated with maternal HBV infection and most of the HBsAg-positive children in the survey received HepB3, HepB-BD may prevent MTCT and chronic HBV infection.

Implementation Approaches for Introducing and Overcoming Barriers to Hepatitis B Birth-Dose Vaccine in sub-Saharan Africa

We discuss determinants of hepatitis B birth-dose vaccine uptake in sub-Saharan Africa countries at the policy, facility, and community levels and propose solutions to known barriers of hepatitis B vaccine introduction in low- and middle-income countries.

In sub-Saharan Africa (SSA), chronic viral hepatitis B (HBV) affects more than 60 million people. Mother-to-child transmission is a major contributor to the ongoing HBV epidemic and yet only 11 of 54 (20.3%) SSA countries have introduced the birth dose of HBV vaccine (HepB-BD) into their regular immunization schedule. As more African countries adopt HepB-BD, implementation approaches must be targeted to ensure effective and timely HepB-BD delivery, especially in rural and under-resourced settings. We conducted a systematic literature review of published literature using PubMed. We included 39 articles published from January 2010 to August 2020, as well as gray literature, case studies, and research performed in SSA. We describe barriers to the uptake of HepB-BD in SSA at the policy, facility, and community levels and propose solutions that are relevant to stakeholders wishing to introduce HepB-BD. We highlight the importance and challenge of reaching infants who are born outside of health care facilities (i.e., home deliveries) with HepB-BD in partnership with community health workers. We also discuss the critical role of maternal education and community engagement in future HepB-BD scale-up efforts in SSA.

Enduring Challenges despite Progress in Preventing Mother-to-Child Transmission of Hepatitis B Virus in Angola

Sub-Saharan Africa has one of the highest rates of hepatitis B virus (HBV) infection globally, with an incidence of 1.5 million and 0.8 million yearly deaths, which drives synergistic efforts towards its elimination. To assess the risk of mother-to-child transmission of HBV infection, a cross-sectional study was conducted on 1012 pregnant women in Angola to investigate HBV serological and molecular profiles. The prevalence of HBV was 8.7% (n = 88), with hepatitis B core IgM antibody (anti-HBc IgM) positivity identified in 12.8%, hepatitis B "e" antigen (HBeAg) positivity in 30%, and HBV DNA ≥ 200,000 IU/mL in 28.2%. Family tracking studied 44 children, of which 11 (25%) received at least two doses of the hepatitis B vaccine. HBV was detected in 10/44 (22.7%) children, with vaccination reported in one infected child. Further testing identified anti-HBc IgM positivity in 3/10 (30%), HBeAg positivity in 55%, and both seromarkers in 20%. The results revealed the importance of antenatal HBV screening, antiviral prophylaxis for mothers with high viral loads or HBeAg positivity, and timely first-dose hepatitis B vaccines in newborns. Anti-HBc IgM positivity among pregnant women and children highlights prophylactic measures worth considering, including antenatal hepatitis B vaccination and catch-up vaccination to young children.

Cost-effectiveness of adding a birth dose of hepatitis B vaccine in the Dafra district of the Hauts-Bassins Region in Burkina Faso (NéoVac Study)

BACKGROUND

The World Health Organization (WHO) recommends a first hepatitis B vaccine dose within 24 h of birth (HepB-BD) to prevent mother-to-child transmission. Evidence for this strategy's economic value in Africa is limited. We assessed the costs and cost-effectiveness of adding HepB-BD to the current three-dose pentavalent schedule (HepB3) in the Dafra district of the Hauts-Bassins Region in Burkina Faso.

METHODS

Using a decision tree combined with a Markov model, we estimated the expected number of life-years (LY) and disability-adjusted life-years (DALYs) saved, incremental costs, and incremental cost-effectiveness ratios (ICER) of HepB-BD + HepB3 versus HepB3 alone in Dafra's 2017 birth cohort (n = 11,462). Institutional delivery rates, vaccine coverage, and vaccination costs from a health system perspective were estimated from field-collected data. We estimated the effectiveness of HepB-BD, age-specific transition probabilities, and horizontal transmission risks using data from previous African studies. Costs and health outcomes were discounted at an annual rate of 3%. We conducted one-way and probabilistic sensitivity analyses to assess uncertainty.

RESULTS

In the base-case analysis without discounting, HepB-BD + HepB3 yielded a net cost saving of US$18,979 and saved 163 DALYs compared with HepB3 alone. With discounting, HepB-BD + HepB3 compared with HepB3 resulted in an incremental cost of US$554 and 31 DALYs averted, translating into an ICER of US$18/DALY averted. In one-way sensitivity analyses, HepB-BD + HepB3 remained cost-effective (at the cost-effectiveness threshold of US$671 i.e. the Burkina Faso per-capita gross domestic product) for all parameter changes. However, results were very sensitive to variations in HepB-BD unit cost per vaccinated neonate and perinatal transmission risk in mothers carrying the hepatitis B e antigen. The probabilities of HepB-BD + HepB3 being cost-effective were 71.7% and 86.7%, at the cost-effectiveness thresholds of US$335 and US$671, respectively.

CONCLUSION

Introducing HepB-BD in Burkina Faso is likely to be cost-effective.

Hepatitis B Vaccination in Senegalese Children: Coverage, Timeliness, and Sociodemographic Determinants of Non-Adherence to Immunisation Schedules (ANRS 12356 AmBASS Survey)

Detailed knowledge about hepatitis B virus (HBV) vaccination coverage and timeliness for sub-Saharan Africa is scarce. We used data from a community-based cross-sectional survey conducted in 2018–2019 in the area of Niakhar, Senegal, to estimate coverage, timeliness, and factors associated with non-adherence to the World Health Organisation-recommended vaccination schedules in children born in 2016 (year of the birth dose (BD) introduction in Senegal) and 2017–2018. Vaccination status was assessed from vaccination cards, surveillance data, and healthcare post vaccination records. Among 241 children with available data, for 2016 and 2017–2018, respectively, 31.0% and 66.8% received the BD within 24 h of birth (BD schedule), and 24.3% and 53.7% received the BD plus at least two pentavalent vaccine doses within the recommended timeframes (three-dose schedule). In logistic regression models, home birth, dry season birth, and birth in 2016 were all associated with non-adherence to the recommended BD and three-dose schedules. Living over three kilometres from the nearest healthcare post, being the firstborn, and living in an agriculturally poorer household were only associated with non-adherence to the three-dose schedule. The substantial proportion of children not vaccinated according to recommended schedules highlights the importance of considering vaccination timeliness when evaluating vaccination programme effectiveness. Outreach vaccination activities and incentives to bring children born at home to healthcare facilities within 24 h of birth, must be strengthened to improve timely HBV vaccination.

Prevention of hepatitis B mother-to-child transmission in Namibia: A cost-effectiveness analysis

Despite access to a safe and effective vaccine, mother-to-child transmission (MTCT) of hepatitis B virus (HBV) persists in Africa. This is of concern since perinatally-infected infants are at highest risk of developing hepatocellular carcinoma, a life-threatening consequence of chronic HBV infection. While tools to prevent HBV MTCT are available, the cost implications of these interventions need consideration prior to implementation. A Markov model was developed to determine the costs and health outcomes of (1) universal HBV birth dose (BD) vaccination, (2) universal BD vaccination and targeted hepatitis B immunoglobulin (HBIG), (3) maternal antiviral prophylaxis using sequential HBV viral load testing added to HBV BD vaccination and HBIG, and (4) maternal antiviral prophylaxis using sequential HBeAg testing combined with HBV BD vaccination and HBIG. Health outcomes were assessed as the number of paediatric infections averted and disability-adjusted life years (DALYs) averted. Primary cost data included consumables, human resources, and hospital facilities. HBV epidemiology, transitions probabilities, disability weights, and the risks of HBV MTCT were extracted from the literature. Incremental cost-effectiveness ratios (ICERs) were calculated to compare successive more expensive interventions to the previous less expensive one. One-way sensitivity analyses were conducted to test the robustness of the model's outputs. At the Namibian cost/DALY averted threshold of US$3 142, the (1) BD vaccination + targeted HBIG, and (2) maternal antiviral prophylaxis with sequential HBeAg testing interventions were cost-effective. These interventions had ICERs equal to US$1909.03/DALY and US$2598.90/DALY averted, respectively. In terms of effectiveness, the maternal antiviral prophylaxis with sequential HBeAg testing intervention was the intervention of choice. The analysis showed that elimination of HBV MTCT is achievable using maternal antiviral prophylaxis with active and passive immunization. There is an urgent need for low cost diagnostic tests to identify those women who will most benefit from drug therapy to attain this laudable goal.

Ending risk-group HBV vaccination for MSM after the introduction of universal infant HBV vaccination: A mathematical modelling study

BACKGROUND

Risk-group HBV vaccination for men who have sex with men (MSM) was introduced in the Netherlands in 2002, followed by universal infant vaccination in 2011, that will enable termination of risk-group vaccination over time. The introduction of pre-exposure prophylaxis (PrEP) for HIV prevention might result in increased HBV testing and vaccination against HBV. The aim of this study was to investigate the impact of the transition from risk-group to universal HBV vaccination, accounting for improvements in HBV testing and treatment, as well as the introduction of PrEP.

METHODS

We developed a mathematical model for HBV transmission among MSM. Universal vaccination was modelled by assigning some MSM (5-15% in 2028 increasing to 80-90% in 2033 and thereafter) to be vaccinated when they become sexually active. We investigated different scenarios assuming 0.5% extra vaccination rate and 0.5% extra testing rate due to PrEP consultations; and 5% of HIV-negative MSM on PrEP, that will reduce the probability of HBV acquisition by 88%.

RESULTS

Universal vaccination resulted in a reduction of 24% (interquartile range; 22-25%) of the total number of HBV infections among MSM estimated to occur from 2020 to 2070. With universal vaccination, terminating risk-group vaccination in 2030 or 2040 resulted in 30% or 10% more HBV infections over 2020-2070, respectively, compared to continuation of risk-group vaccination until 2070. With PrEP and continued risk-group vaccination, the total number of HBV infections over 2020-2070 was reduced by 13%.

CONCLUSIONS

Universal HBV vaccination can lead to a major reduction in HBV incidence among MSM in the future. The reduction becomes smaller when ending risk-group HBV vaccination, but larger by PrEP use for HIV prevention. Efforts to keep high levels of HBV vaccination, testing, and treatment have to be continued in the coming decades in order to eliminate HBV as a health threat for MSM.

Distinct Hepatitis B and HIV co-infected populations in Canada

Due to shared modes of exposure, HIV-HBV co-infection is common worldwide. Increased knowledge of the demographic and clinical characteristics of the co-infected population will allow us to optimize our approach to management of both infections in clinical practice. The Canadian Hepatitis B Network Cohort was utilized to conduct a cross-sectional evaluation of the demographic, biochemical, fibrotic and treatment characteristics of HIV-HBV patients and a comparator HBV group. From a total of 5996 HBV-infected patients, 335 HIV-HBV patients were identified. HIV-HBV patients were characterized by older median age, higher male and lower Asian proportion, more advanced fibrosis and higher anti-HBV therapy use (91% vs. 30%) than the HBV-positive / HIV seronegative comparator group. A history of reported high-risk exposure activities (drug use, high-risk sexual contact) was more common in HIV-HBV patients. HIV-HBV patients with reported high-risk exposure activities had higher male proportion, more Caucasian ethnicity and higher prevalence of cirrhosis than HIV-HBV patients born in an endemic country. In the main cohort, age ≥60 years, male sex, elevated ALT, the presence of comorbidity and HCV seropositivity were independent predictors of significant fibrosis. HIV seropositivity was not an independent predictor of advanced fibrosis (adj OR 0.75 [95%CI: 0.34-1.67]). In conclusion, Canadian co-infected patients differed considerably from those with mono-infection. Furthermore, HIV-HBV-infected patients who report high-risk behaviours and those born in endemic countries represent two distinct subpopulations, which should be considered when engaging these patients in care.

Towards the elimination of viral hepatitis in Thailand by the year 2030

Viral hepatitis is a global problem with mortality comparable to HIV, tuberculosis and malaria. The WHO aims to eliminate hepatitis B (HBV) and hepatitis C (HCV) by 2030. Improved socioeconomic status of developing countries such as Thailand has reduced the incidence and morbidity associated with hepatitis A. Since the beginning of hepatitis B vaccination in all Thai newborns in 1992, at least 95% of one-year-olds are currently receiving 3–4 hepatitis B doses. The second vaccination of newborns of carrier mothers at 1 month of age has contributed to an effective reduction in mother-to-child transmission. Universal vaccination, blood donation screening, and decreasing needle sharing have reduced hepatitis B infection. Under the test and treat model, cost-effective screening at the point-of-care (health center or village hospital) is recommended for adults >30 years-old. Following referral to a tertiary healthcare center for a treatment plan in developing disease management plan, its implementation by trained healthcare professionals is preferably administered at the point-of-care. Hepatitis C prevalence is also decreasing as a result of blood-borne pathogen awareness. Current hepatitis C infection is highest for adults >35 years who were born prior to 1983, with screening is recommend once in their lifetime. Treatment strategy recommendation follows that of hepatitis B. The availability of direct antiviral agents with high cure rates is expected to contribute to the reduction in hepatitis C transmission and mortality as set forth by the WHO policy. Thus, ensuring the successful planning of hepatitis elimination in Thailand requires pilot regional assessment prior to national implementation.

Introduction of birth dose of hepatitis B virus vaccine to the immunization program in Ethiopia: an economic evaluation

BACKGROUND

Hepatitis B virus (HBV) infection is an important cause of morbidity and mortality with a very high burden in Africa. The risk of developing chronic infection is marked if the infection is acquired perinatally, which is largely preventable through a birth dose of HBV vaccine. We examined the cost-effectiveness of a birth dose of HBV vaccine in a medical setting in Ethiopia.

METHODS

We constructed a decision analytic model with a Markov process to estimate the costs and effects of a birth dose of HBV vaccine (the intervention), compared with current practices in Ethiopia. Current practice is pentavalent vaccination (DPT-HiB-HepB) administered at 6, 10 and 14 weeks after birth. We used disability-adjusted life years (DALYs) averted to quantify the health benefits while the costs of the intervention were expressed in 2018 USD. Analyses were based on Ethiopian epidemiological, demographic and cost data when available; otherwise we used a thorough literature review, in particular for assigning transition probabilities.

RESULTS

In Ethiopia, where the prevalence of HBV among pregnant women is 5%, adding a birth dose of HBV vaccine would present an incremental cost-effectiveness ratio (ICER) of USD 110 per DALY averted. The estimated ICER compares very favorably with a willingness-to-pay level of 0.31 times gross domestic product per capita (about USD 240 in 2018) in Ethiopia. Our ICER estimates were robust over a wide range of epidemiologic, vaccine effectiveness, vaccine coverage and cost parameter inputs.

CONCLUSIONS

Based on our cost-effectiveness findings, introducing a birth dose of HBV vaccine in Ethiopia would likely be highly cost-effective. Such evidence could help guide policymakers in considering including HBV vaccine into Ethiopia's essential health services package.

Game-Theoretical Model of Retroactive Hepatitis B Vaccination in China

Hepatitis B (HepB) is one of the most common infectious diseases affecting over two billion people worldwide. About one third of all HepB cases are in China. In recent years, China made significant efforts to implement a nationwide HepB vaccination program and reduced the number of unvaccinated infants from 30 to 10%. However, many individuals still remain unprotected, particularly those born before 2003. Consequently, a catch-up retroactive vaccination is an important and potentially cost-effective way to reduce HepB prevalence. In this paper, we analyze a game theoretical model of HepB dynamics that incorporates government-provided vaccination at birth coupled with voluntary retroactive vaccinations. Given the uncertainty about the long-term efficacy of the HepB vaccinations, we study several scenarios. When the waning rate is relatively high, we show that this retroactive vaccination should be a necessary component of any HepB eradication effort. When the vaccine offers long-lasting protection, the voluntary retroactive vaccination brings the disease incidence to sufficiently low levels. Also, we find that the optimal vaccination rates are almost independent of the vaccination coverage at birth. Moreover, it is in an individual's self-interest to vaccinate (and potentially re-vaccinate) at a rate just slightly above the vaccine waning rate.

Mother-to-child transmission of hepatitis B: What more needs to be done to eliminate it around the world?

Mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is a key component of the hepatitis B burden worldwide. Despite its efficacy to prevent HBV transmission, infant vaccination is not enough to control HBV MTCT. Additional efforts are urgently needed to evaluate and scale-up preventive strategies especially in endemic countries, which are most affected. This review highlights the efficacy and barriers of the currently validated measures for the prevention of HBV MTCT and proposes alternatives adapted to resource-limited settings to eventually achieve HBV elimination worldwide.

Selective Hepatitis B Birth-Dose Vaccination in São Tomé and Príncipe: A Program Assessment and Cost-Effectiveness Study

São Tomé and Príncipe (STP) uses a selective hepatitis B birth-dose vaccination (HepB-BD) strategy targeting infants born to mothers who test positive for hepatitis B virus (HBV) surface antigen. We conducted a field assessment and economic analysis of the HepB-BD strategy to provide evidence to guide development of cost-effective policies to prevent perinatal HBV transmission in STP. We interviewed national stakeholders and key informants to understand policies, knowledge, and practices related to HepB-BD, vaccine management, and data recording/reporting. Cost-effectiveness of the existing strategy was compared with an alternate approach of universal HepB-BD to all newborns using a decision analytic model. Incremental cost-effectiveness ratios (ICERs) were calculated in 2015 USD per HBV-associated death and per chronic HBV case prevented, from the STP health-care system perspective. We found that STP lacked national or facility-specific written policies and procedures related to HepB-BD. Timely HepB-BD to eligible newborns was considered a high priority, although timeliness of HepB-BD was not monitored. Compared with the existing selective vaccination strategy, universal HepB-BD would result in a 19% decrease in chronic HBV infections per year at overall cost savings of approximately 44% (savings of USD 5,441 each year). We estimate an ICER of USD 5,012 saved per HBV-associated death averted. The existing selective HepB-BD strategy in STP could be improved through documentation of policies, procedures, and timeliness of HepB-BD. Expansion to universal newborn HepB-BD without maternal screening is feasible and could result in cost savings if actual implementation costs and effectiveness fall within the ranges modeled.

Prevalence and burden of HBV co-infection among people living with HIV: A global systematic review and meta-analysis

Globally, in 2017 35 million people were living with HIV (PLHIV) and 257 million had chronic HBV infection (HBsAg positive). The extent of HIV-HBsAg co-infection is unknown. We undertook a systematic review to estimate the global burden of HBsAg co-infection in PLHIV. We searched MEDLINE, Embase and other databases for published studies (2002-2018) measuring prevalence of HBsAg among PLHIV. The review was registered with PROSPERO (#CRD42019123388). Populations were categorized by HIV-exposure category. The global burden of co-infection was estimated by applying regional co-infection prevalence estimates to UNAIDS estimates of PLHIV. We conducted a meta-analysis to estimate the odds of HBsAg among PLHIV compared to HIV-negative individuals. We identified 506 estimates (475 studies) of HIV-HBsAg co-infection prevalence from 80/195 (41.0%) countries. Globally, the prevalence of HIV-HBsAg co-infection is 7.6% (IQR 5.6%-12.1%) in PLHIV, or 2.7 million HIV-HBsAg co-infections (IQR 2.0-4.2). The greatest burden (69% of cases; 1.9 million) is in sub-Saharan Africa. Globally, there was little difference in prevalence of HIV-HBsAg co-infection by population group (approximately 6%-7%), but it was slightly higher among people who inject drugs (11.8% IQR 6.0%-16.9%). Odds of HBsAg infection were 1.4 times higher among PLHIV compared to HIV-negative individuals. There is therefore, a high global burden of HIV-HBsAg co-infection, especially in sub-Saharan Africa. Key prevention strategies include infant HBV vaccination, including a timely birth-dose. Findings also highlight the importance of targeting PLHIV, especially high-risk groups for testing, catch-up HBV vaccination and other preventative interventions. The global scale-up of antiretroviral therapy (ART) for PLHIV using a tenofovir-based ART regimen provides an opportunity to simultaneously treat those with HBV co-infection, and in pregnant women to also reduce mother-to-child transmission of HBV alongside HIV.

Innovative strategies for the elimination of viral hepatitis at a national level: A country case series

Viral hepatitis is a leading cause of morbidity and mortality worldwide, but has long been neglected by national and international policymakers. Recent modelling studies suggest that investing in the global elimination of viral hepatitis is feasible and cost-effective. In 2016, all 194 member states of the World Health Organization endorsed the goal to eliminate viral hepatitis as a public health threat by 2030, but complex systemic and social realities hamper implementation efforts. This paper presents eight case studies from a diverse range of countries that have invested in responses to viral hepatitis and adopted innovative approaches to tackle their respective epidemics. Based on an investment framework developed to build a global investment case for the elimination of viral hepatitis by 2030, national activities and key enablers are highlighted that showcase the feasibility and impact of concerted hepatitis responses across a range of settings, with different levels of available resources and infrastructural development. These case studies demonstrate the utility of taking a multipronged, public health approach to: (a) evidence-gathering and planning; (b) implementation; and (c) integration of viral hepatitis services into the Agenda for Sustainable Development. They provide models for planning, investment and implementation strategies for other countries facing similar challenges and resource constraints.

Age, race and viral genotype are associated with the prevalence of hepatitis B e antigen in children and adults with chronic hepatitis B

Hepatitis B e antigen (HBeAg) is an important serological marker of hepatitis B virus (HBV) infection and is associated with higher levels of viraemia, increased risk of infectivity to others and increased risk of hepatocellular carcinoma. We analysed HBeAg status in a large cohort of adults and children enrolled in Cohort Studies of the Hepatitis B Research Network, long-term natural history studies of chronic HBV infection. A cross-sectional analysis examined factors associated with HBeAg positivity, including demographic and virologic data, across the age spectrum. Among 2241 enrolled participants who met criteria for this analysis, 825 (37%) were seropositive for HBeAg. The prevalence of HBeAg was lower in those with older age, ranging from 85% among those up to 10 years of age to only 12% among those older than 50 years. In addition to age, both race and HBV genotype were independently associated with HBeAg positivity. There was a significant interaction between age and race; the prevalence of HBeAg was significantly higher among Asians > 10-30 years old vs Whites or Blacks who were >10 to 30 years old and those infected with HBV genotype C. Conversely, the presence of the basal core promoter and precore variants was associated with significantly lower prevalence of HBeAg, even when adjusted for age, race and genotype. These data will provide a better understanding of factors associated with seropositivity for HBeAg and may lead to better strategies for preventing HBV infection and broader indications for antiviral therapy.

Considerations of antiviral treatment to interrupt mother-to-child transmission of hepatitis B virus in China

Background

Treating high-risk women with antivirals in their third trimester is a promising intervention to further reduce perinatal transmission in neonates born to hepatitis B surface antigen positive [HBsAg(+)] mothers.

Methods

We estimated the number of perinatal infections based on coverage and effectiveness of hepatitis B immunization. We compared cost-effectiveness of different approaches to identify high-risk women for antiviral treatment, by region and urban/rural residence.

Results

Of the 16.59 million live births in 2015, 1.04 million infants (6.3%) were born to HBsAg(+) mothers and 268 201 infants (1.6%) to HBsAg(+) and HBeAg(+) dual-positive mothers. Despite immunoprophylaxis, 51 478 perinatal hepatitis B virus (HBV) transmissions were estimated to have occurred from HBsAg and HBeAg dual-positive mothers in 2015. Using HBeAg or HBV viral load testing to identify high-risk pregnant women and to treat them with Tenofovir, the incremental cost ranged from US$68.2 million to US$90.3 million. Assuming HBV viral load testing is available and used to guide treatment and all women with HBV viral loads >200 000 IU/ml are treated, 25 912 infections would be averted at a projected cost of US$3500 per infection averted.

Conclusions

Identifying high-risk pregnant women and providing them with antiviral treatment is feasible and cost-effective to interrupt perinatal HBV transmissions. Policy options should be urgently explored in order for China to reach the HBV elimination goal of 0.1% prevalence among children by 2030.

The potential impact of the demographic transition in the Senegal-Gambia region of sub-Saharan Africa on the burden of infectious disease and its potential synergies with control programmes: the case of hepatitis B

BACKGROUND

Sub-Saharan Africa (SSA) continues to suffer high communicable disease burdens as its demographic transition (DT) proceeds. Although the consequent changes in population structures influence age-specific contact patterns relevant for transmission, the age distribution of immunity, and the disease burden, investigation of the potential of DT to affect infectious disease epidemiology in regions of SSA has hitherto been overlooked. With a substantial disease burden and complex epidemiology, hepatitis B virus (HBV) represents a prime example of an infection whose epidemiology may be significantly influenced by the DT.

METHODS

An age-structured mathematical model for HBV in the Senegal and Gambia (SG) region was set within a demographic framework with varying vital rates mirroring the entire course of the DT there over 1850-2100, to investigate the effects of the DT on HBV epidemiology, with and without the combined action of vaccination. The model was run from its reconstructed ancien régime (old order) demo-epidemiologic equilibrium and calibrated against SG 1950 age-distribution estimates and Gambian pre-vaccination HBV age-prevalence data.

RESULTS

The model, which reproduced well demographic and HBV age-prevalence data, predicted a complex transition of HBV epidemiology over the course of the DT. This included a prolonged epoch of expansion alongside population growth and rejuvenation until 1990-2000, followed by a dramatic retreat, mainly reflecting projected fertility decline during the twenty-first century. This transitional pattern was mostly explained by the underlying demographically driven changes in horizontal transmission resulting from the changes in the age structure of the population. During 2000-2150 the HBV burden is predicted to decline by more than 70% even in the absence of vaccination.

CONCLUSIONS

Demographic change alone may strongly affect HBV disease burden and shape HBV endemicity. The onset of the demographically driven decline in HBV prevalence, aligned with the expansion of HBV vaccination, forms a synergy potentially boosting effectiveness of control. Such a synergy currently appears to be presenting a "window of opportunity" facilitating HBV elimination which it would be important to exploit and which underlines the importance of taking demographic change into account when assessing the potential longer term impact of vaccination and other control measures.

The current situation and challenges of screening for and treating hepatitis B in sub-Saharan Africa

Hepatitis B virus (HBV) infection is the most important cause of hepatocellular carcinoma in sub-Saharan Africa (SSA). Although the tools to curb the epidemic are known, only a minority of HBV-infected persons are currently diagnosed and treated. Areas covered: We discuss HBV epidemiological trends in SSA, describe important determinants of its natural history, and summarize current knowledge on the continuum of HBV care. Using the results of a systematic review of the literature, we describe the proportion of patients with liver fibrosis at presentation for care. Throughout the manuscript, we highlight major research gaps and explore potential ways to improve uptake of HBV testing, evaluation of liver disease, access to antiviral therapy and monitoring of complications. Expert commentary: Less than 1% of HBV-infected individuals are diagnosed in SSA, despite the availability of rapid tests with good diagnostic accuracy. Up to 15% of individuals enter care with liver cirrhosis, a clear indication for antiviral therapy. Although the proportion of patients eligible for immediate antiviral treatment is generally below 20%, there are few published data from prospective cohort studies. The incidence of hepatocellular carcinoma could be reduced with improved access to antiviral therapy.

How far are we from viral hepatitis elimination service coverage targets?

INTRODUCTION

In 2016, the Global Health Sector Strategy (GHSS) on viral hepatitis called for elimination of viral hepatitis as a major public health threat by 2030 (i.e. 90% reduction in incidence and 65% in mortality). In 2017, WHO's first-ever Global Hepatitis Report presented the baseline values for each of the core indicators of the strategy. We review the challenges and opportunities that lie ahead in order to reach the 2030 service coverage targets.

DISCUSSION

Three-dose coverage of hepatitis B vaccine in infancy reached 84% in 2015 (2030 target: 90%); however, only 39% received the timely birth dose (2030 target: 90%). Blood safety (97% of blood units screened with quality assurance, 2030 target: 100%) and injection safety (5% unsafe injections, 2030 target: 0%) had made substantial progress while harm reduction fell short (27 syringe and needle sets distributed per person who injects drugs per year, 2030 target: 300). Worldwide, 9% and 20% of the HBV- and HCV-infected population respectively, were aware of their status (2030 targets: 90%). In the short term, to reach the 2020 target of diagnosing 50% of those infected, 107 million HBV infected persons and 15 million HCV infected persons should be urgently diagnosed. Overall, in 2015, less than 10% of known infected persons were on HBV treatment or had started HCV treatment (2030 targets: 80%).

CONCLUSIONS

The prevention component of elimination is on track with respect to hepatitis B vaccination, blood safety, and injection safety. However, coverage of the hepatitis B vaccine timely birth dose requires a substantial increase, particularly in sub-Saharan Africa, and harm reduction needs to be taken to scale as injecting drug use accounts for a third of mortality from HCV infection. A promising but limited start in hepatitis testing and treatment needs to be followed by immediate and sustained action so that we reach the service coverage targets required to achieve elimination by 2030. Treating persons coinfected with HIV and hepatitis viruses is particularly urgent and needs to be promoted in the context of the HIV response.

Cost-effectiveness of antiviral prophylaxis during pregnancy for the prevention of perinatal hepatitis B infection in South Korea

BACKGROUND

In Korea, hepatitis B virus (HBV) infection accounts for approximately 65-75% of HBV-related diseases, such as chronic hepatitis and liver cancer, and mother-to-child transmission is presumed to be a major source of the infection. To tackle this issue, the Korean government launched the national Perinatal Hepatitis B Prevention Program (PHBPP) in 2002. This study analyzed the cost-effectiveness of the PHBPP with antiviral prophylaxis compared with the current PHBPP and/or universal vaccination, as well as identified the optimal strategy to eliminate mother-to-child transmission of HBV in Korea.

METHODS

A decision tree model with the Markov process was developed and simulated over the lifetime of a birth cohort in Korea during the year 2014. The current PHBPP providing HBV vaccine and hepatitis B immune globulin to neonates born to HBV positive mothers was compared against two other strategies, universal vaccination of HBV and PHBPP with antiviral prophylaxis, with respect to their costs and health outcomes. The Korean National Health Insurance database was investigated to estimate the costs of HBV-related diseases and utilization of health resources. Costs were assessed from the health care system perspective and converted to 2014 US dollars. Health outcome measures were quality-adjusted life years (QALYs) and number of HBV-related diseases and deaths. Both costs and QALYs were discounted at 5%, following the recommendation of the Health Insurance Review & Assessment Service in Korea. The incremental cost-effectiveness ratio (ICER) obtained from the analysis was evaluated using the willingness-to-pay (WTP) in the Korean society.

RESULTS

PHBPP with antiviral prophylaxis in Korea was cost-effective compared with the current PHBPP. An introduction of antiviral prophylaxis to pregnant women with a high viral load of HBV averted 13 HBV-related deaths per 100,000 people and saved 82 QALYs in total (ICER: $16,159/QALY).

CONCLUSIONS

Considering that WTP in Korea is $29,000, PHBPP with antiviral prophylaxis appears to be a cost-effective strategy. To further decrease the burden of perinatal hepatitis B in Korea, adding antiviral prophylaxis to PHBPP is recommended.

The epidemiology of hepatitis B virus infection in women of reproductive age in highly endemic areas in China

We describe the epidemiology of hepatitis B virus (HBV) infection among women of reproductive age residing in areas of China that are highly endemic for chronic HBV, and provide evidence useful for decision-makers to guide strategies for preventing mother-to-child transmission of HBV, and assess the impact of perinatal transmission PMTCT by projecting HBsAg prevalence trends without interventions. We conducted a cross-sectional HBV serological survey of women, 15-49 years of age, residing in Fujian, Guangdong, Guangxi and Hainan provinces. Demographic and other subject-level data were collected in face-to-face interviews, after which we obtain blood specimens. Specimens were tested for HBV sero-markers by ELISA (Beijing Wantai Biological Pharmacy), and HBV DNA was tested with PCR (Hunan Sansure Biotech). Weighted HBsAg and HBV (either HBsAg+ or anti-HBc+ indicating either present or past infection) prevalences were 11.82% and 57.16%, respectively. Among the HBsAg-positive women, 27% were also HBeAg positive. The proportion of individuals with HBV DNA loads >10⁵ IU/mL declined with increasing age. Among HBsAg-negative women, 0.9% had occult HBV infection. The prevalence of chronic HBV infection among reproductive women in these highly endemic provinces is high, posing a threat to maternal health and risk of mother-to-child transmission. Prevention of mother-to-child transmission remains critically important.

The maternal viral threshold for antiviral prophylaxis of perinatal hepatitis B virus transmission in settings with limited resources: A large prospective cohort study in China

BACKGROUND

Antiviral therapy has been documented to reduce perinatal transmission of hepatitis B virus (HBV) in highly viremic mothers. This large prospective cohort study conducted in China aims to delineate the maternal viral threshold for consideration of antiviral prophylaxis in settings with limited resources.

METHODS

A total of 1177 mother-infant pairs with positive maternal hepatitis B surface antigen (HBsAg) under current passive-active prophylaxis regimen were enrolled from community health centers in Jiangsu and Henan provinces, China. Maternal hepatitis B e antigen (HBeAg) status and viral load were tested at 36-40 weeks of gestation. Post-vaccination serologic testing was performed at 7 and 12 months of age.

RESULTS

HBeAg-positive mothers (419/1177; 35.6%) had significantly higher viral loads, compared with HBeAg-negative mothers (758/1177; 64.4%) (8.12 vs. 2.69 log IU/mL, p < .0001). Twenty infants, born to HBeAg-positive mothers with high viral loads (median, 8.38; range: 7.82-9.22 log IU/mL), were infected at 7 months of age. In contrast, none of the HBeAg-negative mothers transmitted HBV to their offspring. After adjustment for the other risk factor, a higher maternal viral load was significantly associated with a higher risk of transmission (adjusted odds ratio, 3.78; 95% confidence interval: 1.46-9.81; p = .006). The rates of passive-active immunoprophylaxis failure were 0.0% (0/789), 0.0% (0/27), 0.0% (0/32) and 6.1% (20/329) at maternal viral loads of <5, 5-6, 6-7 and ≥7 log IU/mL, respectively. The antibody to hepatitis B surface antigen (anti-HBs) response rate was 98.4% (1138/1157) at 7 months of age.

CONCLUSIONS

Results from this study indicate that the maternal viral threshold associated with perinatal transmission of HBV is 7 log IU/mL, which may be appropriate for consideration of antiviral prophylaxis in settings with limited resources.

Sero-prevalence for Hepatitis B virus among pregnant women attending antenatal clinic in Juba Teaching Hospital, Republic of South Sudan

INTRODUCTION

Hepatitis B virus infection is a major public health problem worldwide and in Africa. This would be the first ever documented study on epidemiology of Hepatitis B infections in the newly formed Republic of South Sudan. This study was designed to estimate the sero-prevalence of Hepatitis B virus infection amongst pregnant women attending antenatal services in Juba.

METHODS

A cross-sectional study was conducted among pregnant women attending antenatal clinic services in Juba Teaching Hospital, in the period between December 2012 and March 2013. Any pregnant woman, attending antenatal care services at Juba Teaching Hospital, was included if she was a resident of Juba County for at least 1 year before pregnancy. A Hepatitis B case was defined as any women participating in the study and was found to be positive for HbsAg and confirmed by ELISA.

RESULTS

This study documented that the prevalence of Hepatitis B surface antigen (HBsAg) among pregnant women attending ANC in Juba was 11% (31 out of the 280 samples). Other samples tested were indeterminate (36%), naturally immune (27.1%), susceptible (23%) and the remaining 1.8% was immune due to vaccination. Significant risk factors for Hepatitis B infection were loss of partner (OR 4.4 and CI of 1.4-13.9) and history of Jaundice (OR 1.7 and CI of 1.2-2.1).

CONCLUSION

These study findings show that only 29% of infants in Juba county are born to immune mothers (naturally or vaccine induced). The remaining 70% of babies would be at risk of infection, if a birth dose of Hepatitis B is not provided. We therefore recommended introduction of Hepatitis B Vaccine birth dose into routine infants' vaccination series to eliminate this risk.

Hepatitis B immunoglobulin during pregnancy for prevention of mother-to-child transmission of hepatitis B virus

BACKGROUND

Hepatitis is a viral infection of the liver. It is mainly transmitted between people through contact with infected blood, frequently from mother to baby in-utero. Hepatitis B poses significant risk to the fetus and up to 85% of infants infected by their mothers at birth develop chronic hepatitis B virus (HBV) infection. Hepatitis B immunoglobulin (HBIG) is a purified solution of human immunoglobulin that could be administered to the mother, newborn, or both. HBIG offers protection against HBV infection when administered to pregnant women who test positive for hepatitis B envelope antigen (HBeAg) or hepatitis B surface antigen (HBsAg), or both. When HBIG is administered to pregnant women, the antibodies passively diffuse across the placenta to the child. This materno-fetal diffusion is maximal during the third trimester of pregnancy. Up to 1% to 9% infants born to HBV-carrying mothers still have HBV infection despite the newborn receiving HBIG plus active HBV vaccine in the immediate neonatal period. This suggests that additional intervention such as HBIG administration to the mother during the antenatal period could be beneficial to reduce the transmission rate in utero.

OBJECTIVES

To determine the benefits and harms of hepatitis B immunoglobulin (HBIG) administration to pregnant women during their third trimester of pregnancy for the prevention of mother-to-child transmission of hepatitis B virus infection.

SEARCH METHODS

We searched the The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, Science Citation Index Expanded (Web of Science), SCOPUS, African Journals OnLine, and INDEX MEDICUS up to June 2016. We searched ClinicalTrials.gov and portal of the WHO International Clinical Trials Registry Platform (ICTRP) in December 2016.

SELECTION CRITERIA

We included randomised clinical trials comparing HBIG versus placebo or no intervention in pregnant women with HBV.

DATA COLLECTION AND ANALYSIS

Two authors extracted data independently. We analysed dichotomous outcome data using risk ratio (RR) and continuous outcome data using mean difference (MD) with 95% confidence intervals (CI). For meta-analyses, we used a fixed-effect model and a random-effects model, along with an assessment of heterogeneity. If there were statistically significant discrepancies in the results, we reported the more conservative point estimate. If the two estimates were equal, we used the estimate with the widest CI as our main result. We assessed bias control using the Cochrane Hepato-Biliary Group suggested bias risk domains and risk of random errors using Trial Sequential Analysis (TSA). We assessed the quality of the evidence using GRADE.

MAIN RESULTS

All 36 included trials originated from China and were at overall high risk of bias. The trials included 6044 pregnant women who were HBsAg, HBeAg, or hepatitis B virus DNA (HBV-DNA) positive. Only seven trials reported inclusion of HBeAg-positive mothers. All 36 trials compared HBIG versus no intervention. None of the trials used placebo.Most of the trials assessed HBIG 100 IU (two trials) and HBIG 200 IU (31 trials). The timing of administration of HBIG varied; 30 trials administered three doses of HBIG 200 IU at 28, 32, and 36 weeks of pregnancy. None of the trials reported all-cause mortality or other serious adverse events in the mothers or babies. Serological signs of hepatitis B infection of the newborns were reported as HBsAg, HBeAg, and HBV-DNA positive results at end of follow-up. Twenty-nine trials reported HBsAg status in newborns (median 1.2 months of follow-up after birth; range 0 to 12 months); seven trials reported HBeAg status (median 1.1 months of follow-up after birth; range 0 to 12 months); and 16 trials reported HBV-DNA status (median 1.2 months of follow-up; range 0 to 12 months). HBIG reduced mother-to-child transmission (MTCT) of HBsAg when compared with no intervention (179/2769 (6%) with HBIG versus 537/2541 (21%) with no intervention; RR 0.30, TSA-adjusted CI 0.20 to 0.52; I² = 36%; 29 trials; 5310 participants; very low quality evidence). HBV-DNA reduced MTCT of HBsAg (104/1112 (9%) with HBV-DNA versus 382/1018 (38%) with no intervention; RR 0.25, TSA-adjusted CI 0.22 to 0.27; I² = 84%; 16 trials; 2130 participants; low quality evidence). TSA supported both results. Meta-analysis showed that maternal HBIG did not decrease HBeAg in newborns compared with no intervention (184/889 (21%) with HBIG versus 232/875 (27%) with no intervention; RR 0.68, TSA-adjusted CI 0.04 to 6.37; I² = 90%; 7 trials; 1764 participants; very low quality evidence). TSA could neither support nor refute this observation as data were too sparse. None of the trials reported adverse events of the immunoglobulins on the newborns, presence of local and systemic adverse events on the mothers, or cost-effectiveness of treatment.

AUTHORS' CONCLUSIONS

Due to very low to low quality evidence found in this review, we are uncertain of the effect of benefit of antenatal HBIG administration to the HBV-infected mothers on newborn outcomes, such as HBsAg, HBV-DNA, and HBeAg compared with no intervention. The results of the effects of HBIG on HBsAg and HBeAg are surrogate outcomes (raising risk of indirectness), and we need to be critical while interpreting the findings. We found no data on newborn mortality or maternal mortality or both, or other serious adverse events. Well-designed randomised clinical trials are needed to determine the benefits and harms of HBIG versus placebo in prevention of MTCT of HBV.

Time trends of chronic HBV infection over prior decades - A global analysis

BACKGROUND & AIMS

Information on trends in chronic hepatitis B virus (HBV) prevalence across countries is lacking. We studied changes in chronic HBV infection over previous decades by country, and assessed patterns of change between and within WHO-defined regions.

METHODS

Based on data from a published systematic review on chronic HBV, we applied a linear model on the logit scale to assess time trends in country-specific prevalence. Estimated HBsAg prevalence in 2000 and relative changes in prevalence over time were evaluated by country and region.

RESULTS

Sufficient data were available for 50 countries, mostly showing reductions in prevalence over time. Various degrees of heterogeneity were observed within regions, with a relatively homogenous pattern in the Eastern Mediterranean region with strong decreases in HBsAg prevalence. Europe showed a mixed pattern: higher and stable chronic HBsAg prevalence in Eastern, and constantly low prevalence in Western Europe. In Africa, some countries demonstrated no change in prevalence; increases were seen in Uganda (odds ratio 1.05 per year; 95% confidence interval 1.04-1.06), Nigeria (1.02; 1.02-1.02), Senegal (1.01; 1.01-1.02), and South Africa (1.02; 1.01-1.02). With some exceptions, country-patterns overlapped among countries of South East Asian and Western Pacific regions, characterized by low-medium HBsAg decreases, most prominent in China and Malaysia.

CONCLUSIONS

Most countries experienced decreases in HBsAg prevalence. Dynamics varied, even within regions; decreases occurred mostly before the direct effects of childhood vaccination may have manifested. These findings together with stable and increasing HBsAg prevalence in some countries of Africa and Eastern Europe indicate the need for further tailored country-specific prevention.

LAY SUMMARY

This study investigated time trends in prevalence of chronic HBV infection in 50 countries worldwide over the last decade, by estimating relative changes in prevalence. Results show decreases in chronic HBV infection in most countries; no changes or increases in prevalence are noted in some African countries. Reasons for time changes need to be investigated further; based on the results, various prevention measures have contributed to reductions, and further tailored HBV prevention is required to combat the disease on a global level.

Pattern transitions in spatial epidemics: Mechanisms and emergent properties

Infectious diseases are a threat to human health and a hindrance to societal development. Consequently, the spread of diseases in both time and space has been widely studied, revealing the different types of spatial patterns. Transitions between patterns are an emergent property in spatial epidemics that can serve as a potential trend indicator of disease spread. Despite the usefulness of such an indicator, attempts to systematize the topic of pattern transitions have been few and far between. We present a mini-review on pattern transitions in spatial epidemics, describing the types of transitions and their underlying mechanisms. We show that pattern transitions relate to the complexity of spatial epidemics by, for example, being accompanied with phenomena such as coherence resonance and cyclic evolution. The results presented herein provide valuable insights into disease prevention and control, and may even be applicable outside epidemiology, including other branches of medical science, ecology, quantitative finance, and elsewhere.

Requirements for global elimination of hepatitis B: a modelling study

BACKGROUND

Despite the existence of effective prevention and treatment interventions, hepatitis B virus (HBV) infection continues to cause nearly 1 million deaths each year. WHO aspires to global control and elimination of HBV infection. We aimed to evaluate the potential impact of public health interventions against HBV, propose targets for reducing incidence and mortality, and identify the key developments required to achieve them.

METHODS

We developed a simulation model of the global HBV epidemic, incorporating data on the natural history of HBV, prevalence, mortality, vaccine coverage, treatment dynamics, and demographics. We estimate the impact of current interventions and scaling up of existing interventions for prevention of infection and introducing wide-scale population screening and treatment interventions on the worldwide epidemic.

FINDINGS

Vaccination of infants and neonates is already driving a large decrease in new infections; vaccination has already prevented 210 million new chronic infections by 2015 and will have averted 1·1 million deaths by 2030. However, without scale-up of existing interventions, our model showed that there will be a cumulative 63 million new cases of chronic infection and 17 million HBV-related deaths between 2015 and 2030 because of ongoing transmission in some regions and poor access to treatment for people already infected. A target of a 90% reduction in new chronic infections and 65% reduction in mortality could be achieved by scaling up the coverage of infant vaccination (to 90% of infants), birth-dose vaccination (to 80% of neonates), use of peripartum antivirals (to 80% of hepatitis B e antigen-positive mothers), and population-wide testing and treatment (to 80% of eligible people). These interventions would avert 7·3 million deaths between 2015 and 2030, including 1·5 million cases of cancer deaths. An elimination threshold for incidence of new chronic infections would be reached by 2090 worldwide. The annual cost would peak at US$7·5 billion worldwide ($3·4 billion in low-income and lower-middle-income countries), but decrease rapidly and this would be accelerated if a cure is developed.

INTERPRETATION

Scale-up of vaccination coverage, innovations in scalable options for prevention of mother-to-child transmission, and ambitious population-wide testing and treatment are needed to eliminate HBV as a major public health threat. Achievement of these targets could make a major contribution to one of the Sustainable Development Goals of combating hepatitis.

FUNDING

Medical Research Council.

Natural history of chronic HBV infection in West Africa: a longitudinal population-based study from The Gambia

BACKGROUND

The natural history of chronic HBV infection in sub-Saharan Africa is unknown. Data are required to inform WHO guidelines that are currently based on studies in Europe and Asia.

METHODS

Between 1974 and 2008, serosurveys were repeated in two Gambian villages, and an open cohort of treatment-naive chronic HBV carriers was recruited. Participants were followed to estimate the rates of hepatitis B e (HBeAg) and surface antigen (HBsAg) clearance and incidence of hepatocellular carcinoma (HCC). In 2012-2013, a comprehensive liver assessment was conducted to estimate the prevalence of severe liver disease.

RESULTS

405 chronic carriers (95% genotype E), recruited at a median age of 10.8 years, were followed for a median length of 28.4 years. Annually, 7.4% (95% CI 6.3% to 8.8%) cleared HBeAg and 1.0% (0.8% to 1.2%) cleared HBsAg. The incidence of HCC was 55.5/100 000 carrier-years (95% CI 24.9 to 123.5). In the 2012-2013 survey (n=301), 5.5% (95% CI 3.4% to 9.0%) had significant liver fibrosis. HBV genotype A (versus E), chronic aflatoxin B1 exposure and an HBsAg-positive mother, a proxy for mother-to-infant transmission, were risk factors for liver fibrosis. A small proportion (16.0%) of chronic carriers were infected via mother-to-infant transmission; however, this population represented a large proportion (63.0%) of the cases requiring antiviral therapy.

CONCLUSIONS

The incidence of HCC among chronic HBV carriers in West Africa was higher than that in Europe but lower than rates in East Asia. High risk of severe liver disease among the few who are infected by their mothers underlines the importance of interrupting perinatal transmission in sub-Saharan Africa.

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.

Cost-Effectiveness Analysis of Hepatitis B Vaccination Strategies to Prevent Perinatal Transmission in North Korea: Selective Vaccination vs. Universal Vaccination

BACKGROUND

To tackle the high prevalence of Hepatitis B virus (HBV) infection in North Korea, it is essential that birth doses of HBV vaccines should be administered within 24 hours of birth. As the country fails to provide a Timely Birth Dose (TBD) of HBV vaccine, the efforts of reducing the high prevalence of HBV have been significantly hampered.

METHODS

To examine the cost-effectiveness of vaccination strategies to prevent perinatal transmission of HBV in North Korea, we established a decision tree with a Markov model consisting of selective, universal, and the country's current vaccination program against HBV. The cost-effectiveness analysis was performed from societal and payer's perspectives and evaluated by Disability Adjusted Life Year (DALY).

RESULTS

The results suggest that introducing the universal vaccination would prevent 1,866 cases of perinatal infections per 100,000 of the birth cohort of 2013. Furthermore, 900 cases of perinatal infections per 100,000 could be additionally averted if switching to the selective vaccination. The current vaccination is a dominated strategy both from the societal and payer's perspective. The Incremental Cost-Effectiveness Ratio (ICER) between universal and selective vaccination is $267 from the societal perspective and is reported as $273 from the payer's perspective.

CONCLUSION

Based on the assumption that the 2012 Gross Domestic Product (GDP) per capita in North Korea, $582.6 was set for cost-effectiveness criteria, the result of this study indicates that selective vaccination may be a highly cost-effective strategy compared to universal vaccination.

The clinical implications of hepatitis B virus genotypes and HBeAg in pediatrics

Although a successful vaccine against HBV has been implemented in 184 countries, eradication of hepatitis B virus (HBV) is still not on the horizon. There are over 240 million chronic carriers of HBV globally. The risk of developing chronic hepatitis ranges from >90% in newborns of hepatitis Be antigen (HBeAg)‐positive mothers, 25%–35% in children under 5 years of age and <5% in adults. HBeAg, a non‐particulate viral protein, is a marker of HBV replication. This is the only HBV antigen to cross the placenta, leading to specific unresponsiveness of helper T cells to the capsid protein and HBeAg in newborns. HBeAg is tolerated in utero and acts as a tolerogen after birth. Perinatal transmission is frequent when mothers are HBeAg‐positive, whereas it occurs less frequently when mothers are HBeAg‐negative. Sequence heterogeneity is a feature of HBV. Based on an intergroup divergence >7.5% across the complete genome, HBV is classified phylogenetically into at least nine genotypes. With between ~4% and 8% intergroup nucleotide divergence, genotypes A–D, F, H and I are classified further into subgenotypes. HBV genotypes/subgenotypes may have distinct geographical distribution and can develop different mutations in the regions of the HBV genome that code for HBeAg. These differences can be related to the role of HBV genotypes to the natural history of infection and mode of transmission. Thus genotypes/subgenotypes of HBV can be responsible for the different natural history of infection and modes of transmission in children, found in various regions of the world, where different genotypes/subgenotypes prevail. Copyright © 2016 John Wiley & Sons, Ltd.

Seroprevalence of hepatitis B among pregnant women in Varna Region, Bulgaria

The aim of the present study was to assess the prevalence of hepatitis B surface antigen among pregnant women in Varna Region, Bulgaria. During the period 2009-2013, an average prevalence of 2.26% (95%CI 1.75, 2.91) was measured in a total number of 2,700 samples. Analysis demonstrated that rural residence and minority ethnic origin are important risk factors for hepatitis B infection among pregnant women with hazard ratios of 2.40 (95%CI 1.46, 3.94), and 2.43 (95%CI 1.46, 4.05) when compared with urban residence and ethnic majority origin, respectively. J. Med. Virol. 88:2012-2015, 2016. © 2016 Wiley Periodicals, Inc.

Hepatitis B and human immunodeficiency virus co-infection among pregnant women in resource-limited high endemic setting, Addis Ababa, Ethiopia: implications for prevention and control measures

BACKGROUND

Hepatitis, a highly contagious viral infection, is one of the leading killer diseases globally caused by hepatitis virus. Among the existing viral causes for hepatic failure, hepatitis B virus (HBV) plays a significant role with devastating implications, especially when combined with other viral infections such as human immunodeficiency virus (HIV). Co-infection with hepatitis B virus and HIV leads to increased morbidity and mortality as compared to independent HIV and HBV infections. In this study, we aimed to assess the seroprevalence of HBV and HIV coinfection and associated risk factors among pregnant women in a selected hospital facility around Addis Ababa, Ethiopia.

METHODS

A total of 215 pregnant women were recruited between July and October 2014 from Tirunesh Beijing General Hospital. A pretested and structured questionnaire was used to collect socio-demographic characteristics and possible risk factors. In addition, 5 ml venous blood was collected and centrifuged to estimate the seroprevalence of HBV and HIV. Descriptive statistics and logistic regression analysis were done and a P value less than 0.05 was considered statistically significant.

RESULTS

The overall prevalence of hepatitis B virus infection was 13 (6%). This positivity was different across different age categories: 1 (11.1%), 3 (4.5%), 6 (6%), 1 (3.2%), and 2 (25%) among those between 15-19, 20-24, 25-29, 30-34, and 35-39 years, respectively. However, a statistically significant association was not established between age and HBV. Among the total, 9 (4.2%) of the positive cases were detected among primary school completed. Multivariate analyses indicated that history of abortion (p = 0.003), history of surgery (p = 0.0.022), and tattooing (p = 0.033) were significantly associated with HBV infection. A total of 9 (4.2%) women were found to be HIV seropositive, of whom 2 (22.2%) were co-infected with HBV.

CONCLUSIONS

We observed a relatively higher seroprevalence of HBV infection among pregnant women in the study area, in which majority of the cases had underlying risk factors for acquiring the infection. Since none of the mothers were vaccinated for HBV, the possibility of perinatal transmission is inevitable. Hence, routine screening and immunization against HBV during pregnancy and health education are highly warranted to alleviate the situation.

Immunization of babies born to HBsAg positive mothers: An audit on the delivery and completeness of follow up in Norfolk and Suffolk, United Kingdom

Perinatal transmission of hepatitis B infection has increased in the UK over the last decade. Routine antenatal screening of pregnant mothers (based on HBsAg) provides an effective means to identify 'at risk' babies. Follow up of babies born to infected mothers involves 4 doses of vaccination and/or a single dose of HBIG at birth. In this study we report the outcome of follow up of babies born to infected mothers over a 5 y period. One hundred sixty-three babies born to HBsAg positive mothers were followed up to ascertain the completeness for immunization and serological testing. Vaccination completion was 99.4% (162 of babies) at birth (1st dose), 95.6% (152 babies) for the second dose (at 1st month), 94.3 % (148 babies) for the 3rd dose (at 2nd month) and 83.4% (106 babies) for the 4th dose (at 12 months). Additionally, at 12 months 29.9% (38) of babies had their blood tested serologically to ascertain infection status; all babies receiving antigen testing were HBsAg negative. The overall vaccination coverage was good, although there is scope to improve the coverage of 4th dose. However, the proportion of children who were serologically tested for surface antigen at 12 months was considerably lower and there is a greater need to test babies concurrently at the time of giving the 4(th) dose. The proposed dried blood spot testing which will be rolled out from September 2014 should address this issue.

Protective immune barrier against hepatitis B is needed in individuals born before infant HBV vaccination program in China

The hepatitis B prevalence rate in adults is still at a high to intermediate level in China. Our purpose was to explore the incidence rate and protective immune barrier against hepatitis B in adults in China. A sample of 317961 participants was multi-screened for hepatitis B surface antigens (HBsAg) in a large-scale cohort of the National Hepatitis B Demonstration Project. A total of 5401 persons were newly-infected, representing an incidence rate of 0.81 (95% CI: 0.77–0.85) per 100 person-years after adjusted by gender and age. History of acquired immune deficiency syndrome, birth prior to 1992, coastal residence, family history of HBV, and migrant worker status were significantly associated with higher incidence, while HBV vaccination and greater exercise with lower incidence. The hepatitis B surface antibody (HBsAb) positive rate was negatively correlated with the incidence rate of hepatitis B (r = −0.826). Linear fitting yielded an incidence rate of 1.23 plus 0.02 multiplied by HBsAb positive rate. The study firstly identified the HBsAg incidence rate, which was reduced to 0.1 per 100 person-years after vaccination coverage of about 64%. The protective immune barrier against hepatitis B needs to be established in individuals born prior to the advent of infant HBV vaccination.