Hepatitis B vaccination in infancy in The Gambia: protection against carriage at 9 years of age

Prevalence of hepatitis B infection in the Gambian population: A narrative review of recent developments

Hepatitis B is a "silent epidemic", fifty to a hundred (50-100) times more infectious than HIV, a potentially life-threatening liver infection caused by the hepatitis B virus (HBV). HBV can cause acute and chronic infection and subsequently results in a high risk of death from cirrhosis and liver cancer. Despite the availability of a safe and effective vaccine, HBV continues to be a global burden including in The Gambia. This study reviewed the recent trends in the epidemiological characteristics of HBV in the Gambia. The researchers conducted an online literature search for primary studies on HBV prevalence published in the past two decades from Jan 1992 to Feb 2022 inclusive on Google Scholar, PubMed, and Scopus. All retrieved studies were assessed for eligibility according to specific inclusion/exclusion criteria, data completeness, and methodological coherence. We found that HBV infection prevalence is above 8% in The Gambia. Moreover, HBV is the most common cause of hepatocellular carcinoma (HCC) in Gambia. Liver cirrhosis and HCC have the highest mortality contribution among hepatitis patients, with occult HBV carriers as major culprits. Also, vaccination coverage has declined from 91% to 88% according to reports from current literature. To achieve the WHO goal of eliminating HBV by 2030, policies targeting infection transmission control among risk groups, community awareness programs, research, price reduction of drugs, mass vaccinations, and diagnostics should be urgently instituted.

Clinical manifestation, staging and prognosis of hepatocellular carcinoma in Gambian patients

BACKGROUND

As a result of the lack of screening programs and the difficulty in making a proper diagnosis, the majority of hepatocellular carcinoma (HHC) patients present late in low-resource countries. The study therefore assesses the clinical features, stage and prognostic variables of patients with HCC in The Gambia.

METHODS

From December 2015 to January 2019, patients with a confirmed diagnosis of HCC were enrolled. All patients' medical history, ultrasound scan, FibroScan and laboratory details were collected.

RESULTS

Two hundred and sixty (260) patients were enrolled. The mean age of HCC patients was 40 years, and 210 (80.7%) of them were male. The most common gastrointestinal symptoms were early satiety 229 (88.1%) and abdominal pain 288 (87.7%), while the most common constitutional symptoms were weight loss 237 (91.2%) and easy fatiguability 237 (91.2%). Hepatomegaly 205 (78.8%) was the most common sign. On ultrasound scan, lesions were mostly multifocal 175 (67.3%), and the median FibroScan score was 75 kPa. The median fibrosis 4 and aspartate transferase platelet ratio index were 4.6 and 2.2, respectively. Hepatitis B surface antigen (HBsAg) was positive in 170 (65.4%) patients, and the median AFP level was 3263 ng/ml. HCC patients with positive HBsAg were more likely to be male 145 (85.3%) vs 62 (72.1%) (p = 0.011), much younger 39.9 vs 51.4 yrs (p =  < 0.0001), more likely to have abdominal pain 156 (91.8%) vs 68 (79.1%) (p = 0.002), jaundice 78 (45.9%) vs 29 (33.7%) (p = 0.042), dark urine 117 (68.8%) vs 46 (53.5%) (p = 0.018), raised transaminases (Aspartate transaminases 224.5 (32-7886) vs 153 (18-610), p =  < 0.01, Alanine transferases 71 (5-937) vs 47 (8-271), p =  < 0.001) and decreased platelet count 207 (33-941) vs 252 (52- 641) (p = 0.021) compared to patients with HCC who were HBsAg-negative.

CONCLUSIONS

The prognosis of patients with HCC is poor in developing countries such as The Gambia, where screening programs and treatment modalities are scarce. Young males are disproportionately affected, and HBV is a major cause of HCC in The Gambia.

Catch-up vaccination and enhanced immunization against hepatitis B, hepatitis A, measles, mumps, rubella and varicella in children with idiopathic thrombocytopenic purpura

BACKGROUND

Limited data exist about the vaccination of children with idiopathic thrombocytopenic purpura (ITP) against vaccine preventable diseases. This study identified the vaccination status of children with ITP against hepatitis A, hepatitis B, measles, mumps, rubella and varicella, completed the immunization of children with inadequate immunization, re-evaluated post-vaccination antibody titers and identified probable vaccination-related complications.

PATIENTS AND METHODS

All of 46 children had chronic ITP were included. Seroconversion of hepatitis A, hepatitis B, varicella, measles, rubella and mumps vaccines was screened. All children with seronegative antibodies against vaccine preventable disease were given a vaccination appointment. Antibody levels were re-measured during a period ranging from 1 to 6 months. Potential complications were detected.

RESULTS

There were 46 children with a mean age of 12.25 years. All children had chronic ITP and received intravenous immunoglobulin at least once previously. Considering the vaccination status, 50% (23 children) had vaccinations appropriate for their age, 47.8% (22 children) did not know their vaccination status and 2.2% (1 patient) did not have vaccinations. Seven children (15.2%) were seropositive for all antibody types and the remaining 39 children were scheduled for vaccination. Post-vaccination antibody titers confirmed that all children became seropositive for each disease. There was no complication in any patient.

CONCLUSION

Immunization against hepatitis B, hepatitis A, measles, mumps, rubella and varicella is insufficient in a considerable number of children with ITP, Hepatitis B Virus (HBV) and Hepatitis A Virus (HAV) immunization being the most frequently inadequate. After immunization, adequate seroconversion levels were achievable without complications.

Global, regional, and national burden of hepatitis B, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

Background

Combating viral hepatitis is part of the UN Sustainable Development Goals (SDGs), and WHO has put forth hepatitis B elimination targets in its Global Health Sector Strategy on Viral Hepatitis (WHO-GHSS) and Interim Guidance for Country Validation of Viral Hepatitis Elimination (WHO Interim Guidance). We estimated the global, regional, and national prevalence of hepatitis B virus (HBV), as well as mortality and disability-adjusted life-years (DALYs) due to HBV, as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. This included estimates for 194 WHO member states, for which we compared our estimates to WHO elimination targets.

Methods

The primary data sources were population-based serosurveys, claims and hospital discharges, cancer registries, vital registration systems, and published case series. We estimated chronic HBV infection and the burden of HBV-related diseases, defined as an aggregate of cirrhosis due to hepatitis B, liver cancer due to hepatitis B, and acute hepatitis B. We used DisMod-MR 2.1, a Bayesian mixed-effects meta-regression tool, to estimate the prevalence of chronic HBV infection, cirrhosis, and aetiological proportions of cirrhosis. We used mortality-to-incidence ratios modelled with spatiotemporal Gaussian process regression to estimate the incidence of liver cancer. We used the Cause of Death Ensemble modelling (CODEm) model, a tool that selects models and covariates on the basis of out-of-sample performance, to estimate mortality due to cirrhosis, liver cancer, and acute hepatitis B.

Findings

In 2019, the estimated global, all-age prevalence of chronic HBV infection was 4·1% (95% uncertainty interval [UI] 3·7 to 4·5), corresponding to 316 million (284 to 351) infected people. There was a 31·3% (29·0 to 33·9) decline in all-age prevalence between 1990 and 2019, with a more marked decline of 76·8% (76·2 to 77·5) in prevalence in children younger than 5 years. HBV-related diseases resulted in 555 000 global deaths (487 000 to 630 000) in 2019. The number of HBV-related deaths increased between 1990 and 2019 (by 5·9% [–5·6 to 19·2]) and between 2015 and 2019 (by 2·9% [–5·9 to 11·3]). By contrast, all-age and age-standardised death rates due to HBV-related diseases decreased during these periods. We compared estimates for 2019 in 194 WHO locations to WHO-GHSS 2020 targets, and found that four countries achieved a 10% reduction in deaths, 15 countries achieved a 30% reduction in new cases, and 147 countries achieved a 1% prevalence in children younger than 5 years. As of 2019, 68 of 194 countries had already achieved the 2030 target proposed in WHO Interim Guidance of an all-age HBV-related death rate of four per 100 000.

Interpretation

The prevalence of chronic HBV infection declined over time, particularly in children younger than 5 years, since the introduction of hepatitis B vaccination. HBV-related death rates also decreased, but HBV-related death counts increased as a result of population growth, ageing, and cohort effects. By 2019, many countries had met the interim seroprevalence target for children younger than 5 years, but few countries had met the WHO-GHSS interim targets for deaths and new cases. Progress according to all indicators must be accelerated to meet 2030 targets, and there are marked disparities in burden and progress across the world. HBV interventions, such as vaccination, testing, and treatment, must be strategically supported and scaled up to achieve elimination.

Funding

Bill & Melinda Gates Foundation.

The Role of Noncommunicable Diseases in the Pursuit of Global Health Security

Noncommunicable diseases and their risk factors are important for all aspects of outbreak preparedness and response, affecting a range of factors including host susceptibility, pathogen virulence, and health system capacity. This conceptual analysis has 2 objectives. First, we use the Haddon matrix paradigm to formulate a framework for assessing the relevance of noncommunicable diseases to health security efforts throughout all phases of the disaster life cycle: before, during, and after an event. Second, we build upon this framework to identify 6 technical action areas in global health security programs that are opportune integration points for global health security and noncommunicable disease objectives: surveillance, workforce development, laboratory systems, immunization, risk communication, and sustainable financing. We discuss approaches to integration with the goal of maximizing the reach of global health security where infectious disease threats and chronic disease burdens overlap.

The Prevalence of Hepatitis B Virus Markers among Students of Shiraz University of Medical Sciences

Background

Protection against hepatitis B virus (HBV) is based on the presence of antibodies against hepatitis B surface antigen (HBsAg). Vaccination of newborns is the most effective means of prevention. This study aimed to evaluate the frequency of anti-HBs antibody (anti-HBsAb), anti-HB core Ab (anti-HBcAb), HBsAg, and HBV DNA among university students in Fars province, Southern Iran.

Materials and Methods

In this cross-sectional study, 272 students of Shiraz University of Medical Sciences, were enrolled. Venous blood (5 mL) was collected from each participant and centrifuged; the sera were stored at -20°C until use. Anti-HBsAb, Anti-HBcAb, and HBsAg were measured using a commercial enzyme-linked immunosorbent assay kit. HBV DNA load was also measured by a real-time polymerase chain reaction.

Results

The mean age of the participants was 19 ± 1 years. There were 171 (62.9%) females and 101 (37.1%) males. Anti-HBsAb at a protective level (>10 mIU/mL) were detected in the sera of 104 (38.5%) of the cases. Of the anti-HBsAb seropositive participants, 82 were female and 22 were male; the difference between the gender and seropositivity to anti-HBsAb was statistically significant (P = 0.001, odds ratio: 3.3, 95% confidence interval = 1.89-5.79). Anti-HBcAb was detected in only one participant that was negative for both HBsAg and HBV DNA.

Conclusion

Findings of the current study show that more than half of the students do not have a protective level of anti-HBsAb and might be susceptible to HBV infection, indicating the necessity of checking the level of anti-HBsAb as well as a booster dose in high-risk groups.

No evidence of occult HBV infection in population born after mass vaccination

Despite access to efficient hepatitis B virus (HBV) vaccine and universal immunization schedules, HBV infection remains a global health concern. HBV infection has decreased by this program. Nevertheless, breakthrough infections occur due to generation of occult HBV infection (OBI) and surface gene mutants in the immunized population. We aimed to determine the presence of OBI in a population born after initiation of nationwide HBV vaccination in Tehran, Iran. A HBV mass vaccination schedule was launched in Iran in 1993. For this study, we enrolled 1120 cases younger than 24 years. ELISA was applied to evaluate the presence of HBsAg, anti-HBs and anti-HBc. HBV-DNA presence was determined in all HBsAg-negative cases using nested polymerase chain reaction. The prevalence of HBsAg, anti-HBc and anti-HBs was 0.1, 0.54 and 39.9% respectively. Out of 6 anti-HBc-positive individuals, 4 cases also had anti-HBs. One case revealed HBsAg co-existence and the other one showed isolated anti-HBc. HBV-DNA was not detected in HBsAg-negative specimens. A very low prevalence of HBsAg and isolated anti-HBc was observed and no occult HBV infection was detected. It seems that evasion mutants are not a potential threat for HBV universal immunization efficacy in the vaccinated population.

Call to Action: Prevention of Mother-to-Child Transmission of Hepatitis B in Africa

Hepatitis B virus (HBV) is a significant public health issue that has not been adequately addressed, especially in the high-prevalence region of Africa. Despite the incorporation of HBV vaccines into the Expanded Program on Immunization, children continue to be infected with HBV through maternal-to-child transmission (MTCT). The addition of a birth dose of HBV vaccine would be a cost-effective method to reduce MTCT. Birth-dose HBV vaccine policies have been adopted in the Western Pacific region but not yet in Africa. Even better protection against HBV MTCT can be achieved by treatment of pregnant women with high HBV viral loads with tenofovir. Tenofovir is already widely used in prevention of HIV MTCT (PMTCT) programs. We suggest that existing HIV PMTCT programs could be expanded to deliver care for HBV-infected pregnant women. With appropriate adoption of birth-dose vaccination policies and expansion of PMTCT programs, elimination of HBV MTCT in Africa is achievable.

Maternal Hepatitis B Infection Burden, Comorbidity and Pregnancy Outcome in a Low-Income Population on the Myanmar-Thailand Border: A Retrospective Cohort Study

Objectives

Hepatitis B virus (HBV) was believed to have minimal impact on pregnancy outcomes apart from the risk of perinatal transmission. In more recent years, there have been reports of adverse associations, most consistently preterm birth (PTB), but this is in the context of high rates of caesarean section. The aim of this study was to explore the association of HBV on pregnancy outcomes in marginalized, low-income populations on the Myanmar-Thailand border.

Methods

HBsAg positive (+) point of care rapid detection tests results were confirmed by immunoassays. Women with a confirmed HBsAg status, HIV- and syphilis-negative at first antenatal care screening, singleton fetus and known pregnancy outcome (Aug-2012 to Dec-2016) were included. Logistic regression analysis was used to evaluate associations between HBV group (controls HBsAg negative, HBsAg+/HBeAg-, or HBsAg+/HBeAg+) and pregnancy outcome and comorbidity.

Results

Most women were tested, 15,046/15,114 (99.6%) for HBV. The inclusion criteria were not met for 4,089/15,046 (27.2%) women due mainly to unavailability of pregnancy outcome and nonconfirmation of HBsAg+. In evaluable women 687/11,025 (6.2%) were HBsAg+, with 476/11,025 (4.3%) HBsAg+/HBeAg- and 211/11,025 (1.9%) were HBsAg+/HBeAg+. The caesarean section rate was low at 522/8,963 (5.8%). No significant associations were observed between pregnancy comorbidities or adverse pregnancy outcomes and HBV status.

Conclusions

The results highlight the disease burden of HBV in women on the Myanmar-Thailand border and support original reports of a lack of significant associations with HBsAg+ irrespective of HBeAg status, for comorbidity, and pregnancy outcomes in deliveries supervised by skilled birth attendants.

Incidence and Outcomes after Out-of-Hospital Medical Emergencies in Gambia: A Case for the Integration of Prehospital Care and Emergency Medical Services in Primary Health Care

BACKGROUND

The Gambia is going through a rapid epidemiologic transition with a dual disease burden of infections and non-communicable diseases occurring at the same time. Acute, time-sensitive, medical emergencies such as trauma, obstetric emergencies, respiratory failure, and stroke are leading causes of morbidity and mortality among adults in the country.ProblemData on medical emergency care and outcomes are lacking in The Gambia. Data on self-reported medical emergencies among adults in a selection of Gambian communities are presented in this report.

METHODS

A total of 320 individuals were surveyed from 34 communities in the greater Banjul area of The Gambia using a survey instrument estimating the incidence of acute medical emergencies in an adult population. Self-reported travel time to a health facility during medical emergencies and patterns of health-seeking behavior with regard to type of facility visited and barriers to accessing emergency care, including cost and medical insurance coverage, are presented in this report.

RESULTS

Of the 320 individuals surveyed, 262 agreed to participate resulting in a response rate of 82%. Fifty-two percent of respondents reported an acute medical emergency in the preceding year that required urgent evaluation at a health facility. The most common facility visited during such emergencies was a health center. Eighty-seven percent of respondents reported a travel time of less than one hour during medical emergencies. Out-of-pocket cost of medications accounted for the highest expenditure during emergencies. There was a low awareness and willingness to subscribe to health insurance among individuals surveyed.

CONCLUSION

There is a high incidence of acute medical emergencies among adults in The Gambia which are associated with adverse outcomes due to a combination of poor health literacy, high out-of-pocket expenditures on medications, and poor access to timely prehospital emergency care. There is an urgent need to develop prehospital acute care and Emergency Medical Services (EMS) in the primary health sector as part of a strategy to reduce mortality and morbidity in the country. TourayS, SanyangB, ZandrowG, TourayI. Incidence and outcomes after out-of-hospital medical emergencies in Gambia: a case for the integration of prehospital care and Emergency Medical Services in primary health care. Prehosp Disaster Med. 2018;33(6):650-657.

Impact of universal childhood vaccination against hepatitis B in Ghana: A pilot study

Hepatitis B virus (HBV) infection is of public health importance worldwide. Vaccination against the infection, especially in early childhood has significantly reduced the public health impact. This pilot study was undertaken in Cape Coast Metropolitan area to assess the impact of the introduction of HBV vaccination in children. A cross-sectional multi-stage cluster sampling of 501 pupils from 30 public and private primary and junior high schools within the Cape Coast metropolis. A questionnaire covering basic demographic details and immunisation history were administered to the participants after consent and assent had been sought. Hepatitis B serological test for HBsAg, HBcAb, HBsAb, HBeAg and HbeAb was undertaken using Hepatitis B test kit and capillary blood from the participants. The general prevalence of HBcAb, HBsAg and HBsAb was found to be 3.6, 2.6 and 19.8% respectively. The prevalence of HBcAb was 2.6 and 6.1% among pupils delivered after and before the vaccine programme introduction respectively. Introduction of the vaccination programme in Ghana has had a positive impact on the HBV infection in Ghana.

Hepatitis B virus surface antigen and antibody markers in children at a major paediatric hospital after the pentavalent DTP-HBV-Hib vaccination

OBJECTIVES

The knowledge about outcomes of infant vaccination against HBV infections using the DPT-HepB-Hib vaccine in Ghana is limited. This study therefore investigated the levels of immunity to HBV among children who received the DPT-HepB-Hib vaccine and HBsAg carriage in non-responders. Correlates for non-response or poor response were also investigated.

METHODS

Cross-sectional study. A major paediatric hospital in Accra. Four hundred and twenty four children between the ages of 5 to 32 months who had completed the full vaccination schedule for the DPT-HepB-Hib vaccine.

RESULTS

Of the 424 children, 358 (84.4%) developed anti-HBs while 340 (80.2%) developed ≥10 mIU/ml anti-HBs (sero-protection) and 3 had HBsAg. A binary logistic regression analysis showed that younger children were associated with sero-conversion (p=.022) and sero-protection (p=.021). For anti-HBs titres ≥100 mIU/ml age was a weaker but significant contributor (p=.041), as compared to the number of vaccines from different manufacturers the child used (p=.028). The mean age of those who used a single type of vaccine was higher (14.75 ± 6.056 months; n=268) than those who used vaccines from two or more manufacturers (11.96 ± 4.645 months; n=156), p= <.001 (CI: -3.897 - 1.688), an indication that efforts to procure vaccine from same source when it was initially introduced are waning.

CONCLUSIONS

There is still a residual possibility of infection with HBV in spite of infant vaccination. In the light of possible loss of anamnestic response over time, there is the need to consider a birth dose for HBV vaccination for all neonates or booster dose for infants who may not have received the vaccine at birth. Using vaccines from a single manufacturer is recommended.

FUNDING

None declared.

Strategies for prevention of gastrointestinal cancers in developing countries: a systematic review

Background

Gastrointestinal cancers account for one third of total cancer incidence and mortality in developing countries. To date, there is no systematic synthesis of evidence regarding strategies to prevent gastrointestinal cancers in developing countries. We aimed to provide a systematic overview of studies evaluating strategies for prevention or early detection of the three most common gastrointestinal cancers (gastric, liver and colorectal cancer) in developing countries.

Methods

We searched MEDLINE, Web of Science and WHO Global Index Medicus databases for relevant articles published until October 2016 using combinations of the search terms “gastrointestinal”, “digestive system”, “gastric”, “liver”, “colorectal”, “cancer”, “prevention”, “early detection” and “developing country” (including names).

Results

Overall, 73 articles met the inclusion criteria, providing information on short– and long–term outcomes (up to 30 years) from various intervention studies (∼45% randomized). Trials on hepatitis B vaccination consistently showed vaccine efficacy over time and indicated long–term preventive effects on liver cancer incidence that start to become measurable at the population level. Studies on anti–H. pylori treatment suggested a reduction in gastric cancer incidence reaching statistical significance after long–term follow–up, while evidence regarding a preventive effect in persons with precancerous lesions is still inconclusive. The studies regarding colorectal cancer focused on early detection, ∼90% of which were restricted to intermediate endpoints.

Conclusion

In conclusion, there were a number of studies on gastric and liver cancer prevention in developing countries showing promising results after long–term follow–up. Important next steps include pooled meta–analyses as far as possible given the heterogeneity between studies as well as implementation research.

INASL Position Statements on Prevention, Diagnosis and Management of Hepatitis B Virus Infection in India: The Andaman Statements

Hepatitis B Virus (HBV) infection is one of the major causes of morbidity, mortality and healthcare expenditure in India. There are no Indian consensus guidelines on prevention, diagnosis and management of HBV infection. The Indian National Association for Study of the Liver (INASL) set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for diagnosis and management of HBV infection, relevant to disease patterns and clinical practices in India. The taskforce first identified contentious issues on various aspects of HBV management, which were allotted to individual members of the taskforce who reviewed them in detail. A 2-day round table discussion was held on 11th and 12th February 2017 at Port Blair, Andaman & Nicobar Islands, to discuss, debate, and finalize the consensus statements. The members of the taskforce reviewed and discussed the existing literature threadbare at this meeting and formulated the 'INASL position statements' on each of the issues. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong: 1, weak: 2) thus reflects the quality (grade) of underlying evidence (A, B, C, D). We present here the INASL position statements on prevention, diagnosis and management of HBV in India.

[A plea for introduction of hepatitis B vaccination at birth in Côte d'Ivoire]

The Côte d'Ivoire National Immunization Technical Advisory Group 2015 work plan included elaboration of an opinion on inclusion of hepatitis B vaccination at birth in the Expanded Program on Immunization (EPI) in Côte d'Ivoire. A task force was set up to conduct this assessment according to a systematized method. The task force analysed scientific articles on the burden of hepatitis B in Côte d'Ivoire, the burden of mother-child transmission, the impact of hepatitis B vaccination at birth in countries which have adopted this strategy, the efficacy and safety of hepatitis B vaccine in newborns, the cost-effectiveness of hepatitis B vaccination at birth, and the best strategy to introduce hepatitis B vaccination at birth in the EPI. The National Immunization Technical Advisory Group of Côte d'Ivoire finally recommended introduction of a dose of hepatitis B vaccine at birth in the context of the Expanded Program on Immunization with maintenance of three doses of pentavalent vaccine (DPT-HepB-Hib) at 6, 10, and 14 weeks of age.

The status of hepatitis B control in the African region

The World Health Organization (WHO) African Region has approximately 100 million people with chronic hepatitis B virus (HBV) infection. This review describes the status of hepatitis B control in the Region. We present hepatitis B vaccine (HepB) coverage data and from available data in the published literature, the impact of HepB vaccination on hepatitis B surface antigen (HBsAg) prevalence, a marker of chronic infection, among children, HBsAg prevalence in pregnant women, and risk of perinatal transmission. Lastly, we describe challenges with HepB birth dose (HepB-BD) introduction reported in the Region, and propose strategies to increase coverage. In 2015, regional three dose HepB coverage was 76%, and 16(34%) of 47 countries reported ≥ 90% coverage. Overall, 11 countries introduced HepB-BD; only nine provide universal HepB-BD, and of these, five reported ≥ 80% coverage. From non-nationally representative serosurveys among children, HBsAg prevalence was lower among children born after HepB introduction compared to those born before HepB introduction. However, some studies still found HBsAg prevalence to be above 2%. From limited surveys among pregnant women, the median HBsAg prevalence varied by country, ranging from 1.9% (Madagascar) to 16.1% (Niger); hepatitis B e antigen (HBeAg) prevalence among HBsAg-positive women ranged from 3.3% (Zimbabwe) to 28.5% (Nigeria). Studies in three countries indicated that the risk of perinatal HBV transmission was associated with HBeAg expression or high HBV DNA viral load. Major challenges for timely HepB-BD administration were poor knowledge of or lack of national HepB-BD vaccination guidelines, high prevalence of home births, and unreliable vaccine supply. Overall, substantial progress has been made in the region. However, countries need to improve HepB3 coverage and some countries might need to consider introducing the HepB-BD to help achieve the regional hepatitis B control goal of < 2% HBsAg prevalence among children < 5 years old by 2020. To facilitate HepB-BD introduction and improve timely coverage, strategies are needed to reach both facility-based and home births. Strong political commitment, clear policy recommendations and staff training on HepB-BD administration are also required. Furthermore, high quality nationally representative serosurveys among children are needed to inform decision makers about progress towards the regional control goal.

Development and novel therapeutics in hepatocellular carcinoma: a review

This review summarizes the epidemiological trend, risk factors, prevention strategies such as vaccination, staging, current novel therapeutics, including the drugs under clinical trials, and future therapeutic trends for hepatocellular carcinoma (HCC). As HCC is the third most common cause of cancer-related death worldwide, its overall incidence remains alarmingly high in the developing world and is steadily rising across most of the developed and developing world. Over the past 15 years, the incidence of HCC has more than doubled and it increases with advancing age. Chronic infection with hepatitis B virus is the leading cause of HCC, closely followed by infection with hepatitis C virus. Other factors contributing to the development of HCC include alcohol abuse, tobacco smoking, and metabolic syndrome (including obesity, diabetes, and fatty liver disease). Treatment options have improved in the past few years, particularly with the approval of several molecular-targeted therapies. The researchers are actively pursuing novel therapeutic targets as well as predictive biomarker for treatment of HCC. Advances are being made in understanding the mechanisms underlying HCC, which in turn could lead to novel therapeutics. Nevertheless, there are many emerging agents still under clinical trials and yet to show promising results. Hence, future therapeutic options may include different combination of novel therapeutic interventions.

Short article: Hepatitis B virus status in children born to HIV/HBV coinfected women in a French hospital: a cross-sectional study

OBJECTIVES

We assessed hepatitis B virus (HBV) status in children born to HIV/HBV coinfected women with large access to antiretroviral therapy.

METHODS

All HIV/HBV coinfected pregnant women from 01 January 2000 to 01 January 2012 were included in the retrospective study (NCT02044068). Antiretroviral therapy during pregnancy and injection of HBV immunoglobulin/vaccine to newborns was recorded. We assessed HBV status of children aged at least 2 years.

RESULTS

Twenty-one women (35 children) were studied. Twenty-six children (74%) had HBsAb: 22 had received immunoglobulin and 24 had received a complete vaccine (with immunoglobulin in 21 cases); their mothers had been administered lamivudine or tenofovir/emtricitabine during eight and nine pregnancies, respectively. Eight children (23%) were negative for HBsAg, HBsAb, and HBcAb: four (11.5%) had received immunoglobulin and a complete vaccine; in two children, it was not known whether they had received an immunoglobulin injection; in one child, the vaccine was incomplete; and in the last one, it was not known whether he had received immunoglobulin/vaccine. Their mothers had been administered lamivudine or tenofovir/emtricitabine during five and two pregnancies, respectively. No infant has chronic HBV infection (HBsAg) after prenatal mothers' antiretroviral therapy combined with a complete postnatal HBV protection. One child had HBcAb and HBsAb: it was not known whether she had received an immunoglobulin injection; the vaccine was incomplete. The mother had been administered lamivudine during the last trimester of pregnancy.

CONCLUSION

Antiretroviral therapy in HBV/HIV coinfected women following current national HBV guidelines may prevent mother-to-child-transmission of HBV. Negativity of surrogate markers of vaccine-induced protection is frequent; large studies on long-term protection are needed.

The independent impact of newborn hepatitis B vaccination on reducing HBV prevalence in China, 1992-2006: A mathematical model analysis

OBJECTIVE

To evaluate the independent impact of newborn hepatitis B vaccination on reducing HBV prevalence in China, from its introduction in 1992 to 2006.

METHODS

An age- and time-dependent discrete dynamic model was developed to simulate HBV transmission in China under the assumptions of no any change in interventions and only with newborn vaccination introduction, respectively. The initial conditions of the model were determined according to the national serosurvey in 1992. The simulated results were compared with the observed results of the national serosurvey in 2006, and the contribution rate of newborn vaccination on reducing HBV prevalence was calculated overall and by birth cohort.

RESULTS

The total HBV prevalence would remain stable through the 14-year period if no any change in interventions, but decrease year by year if only with newborn vaccination introduction. Newborn vaccination could account for more than 50% of the reduction of the total HBV prevalence, although the full 3-dose and timely birth dose vaccination coverage rates were low in the early years. The results by birth cohort showed that the higher the two coverage rates, the higher contribution rate on reducing HBV prevalence. For the 2005 birth cohort which had high levels in the two coverage rates, the contribution rate could reach more than 95%.

CONCLUSION

Newborn hepatitis B vaccination from 1992 to 2006 in China had played the most important role in reducing HBV prevalence. Newborn vaccination with high full 3-dose and timely birth dose coverage rates is the decisive factor in controlling hepatitis B in China.

Hepatitis B and A vaccination in HIV-infected adults: A review

Hepatitis B and A account for considerable morbidity and mortality worldwide. Immunization is the most effective means of preventing hepatitis B and A. However, the immune response to both hepatitis vaccines seems to be reduced in HIV-infected subjects. The aim of this review was to analyze the immunogenicity, safety, long-term protection and current recommendations of hepatitis B and A vaccination among HIV-infected adults. The factors most frequently associated with a deficient level of anti-HBs or IgG anti-HAV after vaccination are those related to immunosuppression (CD4 level and HIV RNA viral load) and to the frequency of administration and/or the amount of antigenic load per dose. The duration of the response to both HBV and HAV vaccines is associated with suppression of the viral load at vaccination and, in the case of HBV vaccination, with a higher level of antibodies after vaccination. In terms of safety, there is no evidence of more, or different, adverse effects compared with HIV-free individuals. Despite literature-based advice on the administration of alternative schedules, revaccination after the failure of primary vaccination, and the need for periodic re-evaluation of antibody levels, few firm recommendations are found in the leading guidelines.

Unsolved problems and future perspectives of hepatitis B virus vaccination

Hepatitis B virus (HBV) infection is still a serious worldwide problem, and vaccination is the most effective strategy for primary prevention of the infection. Although universal vaccination may be required for total eradication, several countries, including Japan, have not yet adopted universal vaccination programs. Some individuals are non-responders to HBV vaccine and several mechanisms responsible for their poor response have been proposed. To overcome non-response, third generation vaccines with pre-S proteins have been developed. These vaccines have shown better anti-HBs responses and may also be effective in preventing infection by HBV with S mutant. Improvement of vaccine efficacy by intradermal administration, or co-administration with cytokines or adjuvants, may also be effective in non-responders. The necessity, timing and method of booster vaccination in responders with decreased anti-HBs responses, and effective vaccination against S-mutant HBV, are issues requiring resolution in the global prevention of HBV infection.

Strategy vaccination against Hepatitis B in China

Hepatitis B (HB) is a serious public health problem in China. Up to now, the hepatitis B virus (HBV) vaccination was the most cost-effective way to prevent HBV infection. Since 1992, when the Chinese government prioritized implementing the HBV vaccinations for newborns, China began to see a larger reduction in HBV infections. For children under 5 years, the prevalence of hepatitis B surface antigen (HBsAg) has decreased to 1.0%. However, many additional challenges for the prevention and control of HBV infection in China remain. There is a lack of knowledge of the significant impact of the HBV vaccination for the general public with 93 million HBV carriers and chronic HBV patients as infection sources. Therefore, the HBV vaccine application should focus on the optimization of immunization strategies according to HBV prevalence characteristics, improve the public's knowledge of HBV vaccinations, and help to ensure the protective effects of the HBV vaccine.

Trends of acute hepatitis B notification rates in eastern China from 2005 to 2013

Zhejiang Province was a high endemicity for hepatitis B disease in the 1990's. A number of measures implemented since then have begun to control and prevent hepatitis B. In 1992, hepatitis B vaccine came on the market. In 2002, hepatitis B vaccine was included in the national Expanded Programme on Immunization (EPI). Between 2007 and 2010, catch-up vaccination was implemented for children under 15. Since 2010, vaccination guidelines for high-risk groups have also been adopted. This study evaluated the impact of these control and prevention strategies on acute hepatitis B notification rates from 2005 through 2013. Data from the National Notifiable Disease Reporting System (NNDRS) revealed a steady downward trend in notification rates of acute hepatitis B. The most dramatic decline occurred among pre-adults, highlighting the benefits of EPI's policy of universal vaccination for children. However, the highest notification rates occurred among young adults of lower socio-economic status. These findings indicate the strong need to vaccinate young adults at risk for HBV infection as well as to collect risk-factor information in the NNDRS for monitoring and following up persons with acute hepatitis B.

Evidence for a change in the epidemiology of hepatitis B virus infection after nearly two decades of universal hepatitis B vaccination in South Africa

The hepatitis B vaccine has been part of the South African Expanded Program on Immunization since April 1995 but its long-term impact remains unknown. This study tested 1,206 sera collected from patients aged 1-25 years from various health facilities across the country for HBV serological markers and HBV DNA. Based on the year the vaccine was introduced, samples were stratified by age into pre- and post-vaccine introduction populations, which were then compared for evidence of immunity and chronic carriage using the Chi-square test. Where HIV status was known, subset analyses were performed. Immunity to HBV infection increased from 13.0% in the pre- to 57.0% in the post-vaccine introduction population (P < 0.001). This decreased with increasing age within the post-vaccine introduction population (76.1% for 1-5 years, 50.0% for 6-10 years, and 46.3% for 11-16 years). In addition, HBV chronic carriage was significantly (P = 0.003) reduced in the post- (1.4%) compared to the pre-vaccine introduction population (4.2%). The difference in prevalence of active HBV infection in the serologically exposed pre- and post-vaccine introduction populations was not statistically significant. Subset analyses showed that evidence of immunity was significantly (P < 0.001) higher in the HIV negative compared to the HIV positive subset in both populations. Universal hepatitis B vaccination has been a remarkable success, with a significant increase in immunity to HBV infection. The observation that HBV chronic carriage increases as immunity wanes over time calls into question whether the time has come to consider a pre-adolescence vaccine booster dose policy.

Efficacy and effectiveness of infant vaccination against chronic hepatitis B in the Gambia Hepatitis Intervention Study (1986-90) and in the nationwide immunisation program

BACKGROUND

Gambian infants were not routinely vaccinated against hepatitis B virus (HBV) before 1986. During 1986-90 the Gambia Hepatitis Intervention Study (GHIS) allocated 125,000 infants, by area, to vaccination or not and thereafter all infants were offered the vaccine through the nationwide immunisation programme. We report HBV serology from samples of GHIS vaccinees and unvaccinated controls, and from children born later.

METHODS

During 2007-08, 2670 young adults born during the GHIS (1986-90) were recruited from 80 randomly selected villages and four townships. Only 28% (753/2670) could be definitively linked to their infant HBV vaccination records (255 fully vaccinated, 23 partially vaccinated [1-2 doses], 475 not vaccinated). All were tested for current HBV infection (HBV surface antigen [HBsAg]) and, if HBsAg-negative, evidence of past infection (HBV core-protein antibody [anti-HBc]). HBsAg-positive samples (each with two age- and sex-matched HBsAg-negative samples) underwent liver function tests. In addition, 4613 children born since nationwide vaccination (in 1990-2007) were tested for HBsAg. Statistical analyses ignore clustering.

RESULTS

Comparing fully vaccinated vs unvaccinated GHIS participants, current HBV infection was 0.8% (2/255) vs 12.4% (59/475), p < 0.0001, suggesting 94% (95% CI 77-99%) vaccine efficacy. Among unvaccinated individuals, the prevalence was higher in males (p = 0.015) and in rural areas (p = 0.009), but adjustment for this did not affect estimated vaccine efficacy. Comparing fully vaccinated vs unvaccinated participants, anti-HBc was 27.4% (70/255) vs 56.0% (267/475), p < 0.00001. Chronic active hepatitis was not common: the proportion of HBsAg-positive subjects with abnormal liver function tests (ALT > 2 ULN) was 4.1%, compared with 0.2% in those HBsAg-negative. The prevalence of antibodies to hepatitis C virus was low (0.5%, 13/2592). In children born after the end of GHIS, HBsAg prevalence has remained low; 1.4% (15/1103) in those born between 1990-97, and 0.3% (9/35150) in those born between 1998-2007.

CONCLUSIONS

Infant HBV vaccination achieves substantial protection against chronic carriage in early adulthood, even though approximately a quarter of vaccinated young adults have been infected. This protection persists past the potential onset of sexual activity, reinforcing previous GHIS findings of protection during childhood and suggesting no need for a booster dose. Nationwide infant HBV vaccination is controlling chronic infection remarkably effectively.

The effects of different dosage levels of hepatitis B vaccine as booster on anti-HBs-negative children 5-15 y after primary immunization; China, 2009-2010

The changes in lgG antibody levels to hepatitis B surface antigen (HBsAg) and in antibody to HBsAg (anti-HBs) seroconversion rates due to different dosages of hepatitis B vaccine (HepB) were compared in 2106 children. Children who had been previously vaccinated as infants with HepB were revaccinated at 5-15 y of age, after which the antibody titers were determined. After the first booster dose, the anti-HBs seroconversion rate (defined as an anti-HBs ≥10 mIU/ml) with 10 μg of HepB (93.6%) was significantly greater than the rate with 5 µg of HepB (90.3%) (P<0.05); the anti-HBs seroconversion rate in 10-15-y-old boys vaccinated with 10 μg of HepB (90.9%) was significantly greater than the rate with 5 µg of HepB (84.3%) (P<0.05). The anti-HBs seroconversion rates after the third booster dose with 5 or 10 μg of HepB were greater than those after the first booster dose (99.6% and 99.7%, vs. 90.3% and 93.6%, P<0.05); as was the corresponding GMTs (658 ± 4 mIU/ml and 2599 ± 3 mIU/ml, vs. 255 ± 11 mIU/ml and 877 ± 11 mIU/ml [P<0.05]). The immunization effects of booster vaccination with 3 doses of HepB with 5 or 10 µg are effective; a single booster dose with 10 µg of HepB for 10-15-y-old boys and with 5 or 10 µg of HepB for 5-9 y old boys and for 5-15-y-old girls are effective in generating protective antibody against HBV; however, for anti-HBs-negative children after a single dose of booster, 3 doses are needed.

Rise and fall of HCV-related hepatocellular carcinoma in Italy: a long-term survey from the ITA.LI.CA centres

BACKGROUND & AIMS

Hepatitis C virus (HCV) is the leading aetiological factor of HCC in the western world where, overall, its incidence is increasing, despite data suggesting an initial drop in some areas. The aim of this study was to evaluate epidemiology, clinical features and survival of HCV-related HCC (HCV-HCC) in a wide time range in Italy.

METHODS

Multicentre retrospective study including 3695 patients prospectively recruited by the ITA.LI.CA group. Patients were classified into three subgroups according to aetiology (Group A[GA], pure HCV; Group B[GB], HCV + cofactors; and Group C[GC], non-HCV) and in 5 time cohorts (5 years each), according to the year of diagnosis. Age, gender, Child-Pugh score, modality of diagnosis, stage, presence of thrombosis/metastases, type of treatment and survival were analysed.

RESULTS

A total of 1801 GA patients, 445 GB and 1333 GC were recruited. The number of GA patients peaked in the 1996-2000, gradually dropping thereafter (P < 0.0001), as observed for GB (P < 0.0001). Age at diagnosis increased (P < 0.0001), while percentage of patients diagnosed during surveillance and stage improved only in GA (P = 0.02 and P = 0.003 respectively). The survival significantly increased over time particularly in GA (median 37 months) and was longer in GA than in GB and GC (P < 0.0001).

CONCLUSIONS

The prevalence of HCC-HCV is decreasing in Italy since 2001. HCV-HCC patients are older, more frequently diagnosed under surveillance and in an earlier stage. HCC survival improved in the last 15 years and is significantly higher in patients with HCV-HCC. We therefore expect a further drop in both incidence and mortality for HCV-HCC in the years to come.

Gestational zinc deficiency impairs humoral and cellular immune responses to hepatitis B vaccination in offspring mice

Background

Gestational zinc deficiency has been confirmed to impair the infant immune function. However, knowledge about effects of maternal mild zinc deficiency during pregnancy on hepatitis B vaccine responsiveness in offspring is limited. In this report, we aimed to examine how maternal zinc deficiency during pregnancy influences humoral and cellular immune responses to hepatitis B vaccination in offspring of BALB/c mice.

Methodology/Principal Findings

From day 1 of pregnancy upon delivery, maternal mice were given a standard diet (30 mg/kg/day zinc), zinc deficient diet (8 mg/kg/day zinc), or combination of zinc deficient diet (8 mg/kg/day zinc in the first 2 weeks of gestation) and zinc supplement diet (150 mg/kg/day zinc for the last week of pregnancy), respectively. Newborn pups of these maternal mice were immunized with hepatitis B vaccine at postnatal weeks 0, 2 and 4. Then, splenocytes and blood samples from the offspring mice were harvested for detection of serum zinc concentrations, humoral and cell-mediated immune responses, expression of cytokines using ELISA, CCK-8 and flow cytometric analysis. Results from the present study demonstrated that gestational zinc deficiency inhibited antibody responses, and decreased the proliferative capacity of T cells in offsprings immunized with hepatitis B vaccine. Additionally, HBsAg-specific cytokines analysis revealed that gestational zinc deficiency could inhibit secretion of IFN-γ from splenocytes, and decrease IFN-γ expression of CD4⁺ and CD8⁺ T cells.

Conclusions/Significance

Gestational zinc deficiency can weaken the humoral and cell-mediated immune responses to hepatitis B vaccine via decreasing B cell counts and hepatitis B virus-specific immunoglobulin G production, as well as reducing T cell proliferation, CD4⁺/CD8⁺ T cell ratio, and Th1-type immune responses.

Observational study of vaccine efficacy 24 years after the start of hepatitis B vaccination in two Gambian villages: no need for a booster dose

Objectives

To determine the duration of protection from hepatitis B vaccine given in infancy and early childhood and asses risk factors for HBV infection and chronic infection.

Methods

In 1984 infant HBV vaccination was started in two Gambian villages. Cross sectional serological surveys have been undertaken every 4 years to determine vaccine efficacy. In the current survey 84.6% of 1508 eligible participants aged 1–28 years were tested. A spouse study was conducted in females (aged 14 years and above) and their male partners.

Results

Vaccine efficacy against chronic infection with hepatitis B virus was 95.1% (95% confidence interval 91.5% to 97.1%), which did not vary significantly between age groups or village. Efficacy against infection was 85.4% (82.7% to 87.7%), falling significantly with age. Concentrations of hepatitis B antibody fell exponentially with age varying according to peak response: 20 years after vaccination only 17.8% (95% CI 10.1–25.6) of persons with a low peak response (10–99 mIU/ml) had detectable HBs antibody compared to 27% (21.9% to 32.2%) of those with a high peak response (>999 mIU/ml). Time since vaccination and a low peak response were the strongest risk factors for HBV infections; males were more susceptible, marriage was not a significant risk for females. Hepatitis B DNA was not detected after infection, which tested soley core antibody positive. An undetectable peak antibody response of <10 mIU/ml and a mother who was hepatitis B e antigen positive were powerful risk factors for chronic infection.

Conclusions

Adolescents and young adults vaccinated in infancy are at increased risk of hepatitis B infection, but not chronic infection. Married women were not at increased risk. There is no compelling evidence for the use of a booster dose of HBV vaccine in The Gambia.

The effects of booster vaccination on hepatitis B vaccine in anti-HBs negative infants of HBsAg-positive mothers after primary vaccination

The purpose of this study was to investigate the changes in anti-HBs IgG levels after booster vaccinations in anti-HBs negative infants of HBsAg-positive mothers. After primary vaccination, the immunization effects of different dosages of booster vaccinations of hepatitis B vaccine (CHO) were compared. A group of 472 newborns were vaccinated with three-dose hepatitis B vaccine at birth, 1 mo and 6 mo of age. Blood serum was collected within 6-12 mo after the third dose, and HBsAg, anti-HBs and anti-HBc levels were determined. Of this group, 101 infants who were both anti-HBs and HBsAg negative were revaccinated with 20 μg hepatitis B vaccine (CHO), and their antibody titers were monitored. Among these 101 infants, the anti- HBs positive rates (defined as anti-HBs ≥ 100 mIU/ml) differed after the first and the third dose (79% and 90%, respectively (p<0.05), while differences in the corresponding geometric mean titers (GMTs) were not statistically significant (629 ± 3 mIU/ml and 572 ± 3 mIU/ml respectively, p<0.05). The anti-HBs GMTs after booster vaccination were 10-fold larger than those before booster vaccination. We conclude that a single booster dose is generally adequate for infants of HBsAg-positive mothers, whereas a further booster dose should be given for non-responders.

Revaccination of non- and low- responders after a standard three dose hepatitis B vaccine schedule

BACKGROUND

Guangdong province of China is HBV high endemicity and 1.6 million neonates are administrated 5 μg yeast recombinant anti-HBV vaccine each year. But few studies are performed to evaluate the immunogenicity and revaccination effect on non- and low- responders.

METHODS

2,199 children were administered intramuscularly with 5 μg vaccine at 0, 1 and 6 mo after birth. A 3 ml blood sample was drawn from each infant 1 mo after the third dose for determination of anti-HBs level. Three additional doses (10 μg each) were given to non- and low- responders.

RESULTS

Of 1,814 subjects, 3.1% were non-responders (anti-HBs titer < 10 mIUml (-1) ) and 28.9% were low-responders (anti-HBs ≥ 10 mIUml (-1) and < 100 mIUml (-1) ). Low birth weight (LBW) was a risk factor for non- and low- responders (RR = 1.6, 95%CI = 1.2-2.0). After revaccination, of the 34 non-responders, 14.7% became low-responders and 85.3% became responders. Of the 74 low-responders, 21.6% remained at the same level and 78.4% shifted into responder category.

CONCLUSIONS

Based on the lower responding rate after the primary immunization cycle and the higher responding rate after the additional cycle, measurement of anti-HBs level should be considered for people who had been immunized with three-dose 5 μg HB vaccine in Guangdong, especially for specific populations including LBW infants, healthcare workers, and patients with immunodeficiency disorders. An amount of 10 μg vaccine should be revaccinated to any non- and low- responders to provide adequate seroprotection.

Prevalence of hepatitis B virus infection in a highly endemic area of southern China after catch-up immunization

The Chinese national goals for control of hepatitis B virus (HBV) infection were to achieve a prevalence of HBsAg below 7% for the entire population, and 1% for children under 5-year old, by 2010. To determine whether Guangxi, a multi-minority province with a low socio-economic status and a very high prevalence of HBV, achieved this goal, a seroepidemiological survey of HBV infection was carried out using stratified, random cluster sampling. The results show that the overall prevalence of HBsAg is 9.16% [95% confidence interval (CI) = 8.32-10%]. The prevalence in males (10.96%, 95% CI = 9.64-12.28%) is significantly higher than in females (7.71%, 95% CI = 6.64-8.78%; χ(2) = 10.5923, P < 0.05). The prevalence in children under 5-year old is 3.62% (95% CI = 0.60-6.64%) and increases with age. The prevalence of HBsAg in non-immunized individuals is significantly higher than in those immunized completely, although not within 24 hr of birth (χ(2) = 31.426, P < 0.05); a significant difference was found in those below the age of 20 years but not in older persons. Gender, age, immunization history, and familial HBsAg carriers are risk factors for infection. In conclusion, this study indicates that Guangxi has not reached the goal for the control of HBV infection. Catch-up HBV immunization may not protect adults effectively against infection in highly endemic regions.

Increased seroprevalence of HBV DNA with mutations in the s gene among individuals greater than 18 years old after complete vaccination

BACKGROUND & AIMS

Despite the success of a universal vaccination program against hepatitis B virus (HBV) in Taiwan, a small but substantial proportion of individuals remain infected by mutant viruses that escape the vaccine. We investigated the seroepidemiology and genotypic characteristic of HBV for long periods after neonatal vaccination.

METHODS

We measured hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc), and antibody to hepatitis B surface antigen (anti-HBs) in 1214 serum samples collected throughout Taiwan from individuals 0.6-87.8 years old in 2007. HBV DNA was detected using polymerase chain reaction and sequence analysis in vaccine recipients who tested positive for anti-HBc and/or HBsAg.

RESULTS

The overall seroprevalence of HBsAg and anti-HBc was significantly lower among individuals born after the initiation of the nationwide vaccination program (P < .001). However, we observed increasing seroprevalence of anti-HBc and isolated anti-HBs when subjects were grouped by age: at 10-14, 14-18, to 18-21 years of age, values were 0.4%, 1.9%, and 8.1% (P = .0135) and 43.7%, 55.4%, and 59.6% (P = .0093), respectively (χ(2) test for trend). A large increase was observed in the percentage of patients who tested positive for HBV DNA at 18-21 years of age (3.0% vs 0.2% [P = .002] for all eligible subjects and 5.7% vs 0.3% [P < .001] for subjects vaccinated with ≥3 doses). Five of 8 completely vaccinated individuals who were seropositive for HBV DNA carried variants with mutations in the S gene.

CONCLUSIONS

Universal vaccination effectively controls HBV infection in children and adolescents. However, after adolescence, there is a significant increase in the seroprevalence of anti-HBs, anti-HBc, and HBV DNA, indicating that new preventative strategies are needed for adults.

Twenty years of universal vaccination against hepatitis B in Italy: achievements and challenges

Viral hepatitis B is a vaccine-preventable disease. Vaccination has proved to be safe and highly effective in reducing the incidence, the carrier rate and HBV-related mortality on a global scale. In Italy, universal vaccination against hepatitis B started in 1991 in infants as well as in adolescents, providing an outstanding record of safety and effectiveness. Within a few years, over 95% coverage was consistently reported. Today, some 17 million people are immune against hepatitis B and their immunity has been shown to be long-lasting. At present, no booster is required in healthy vaccinated people to sustain protection. Surveillance data from Italy have shown a clear overall decline in hepatitis B among successfully vaccinated individuals. Furthermore, a generation of children and young people (at present cohorts ranging from 0 to 32 years) is emerging with practically no markers of HBV infection. Italy’s vaccination programme has resulted in substantial progress towards the prevention and control of hepatitis B. The vaccination programme must continue. Maintaining mandatory vaccination of infants and increasing HBV vaccination coverage in high-risk groups, including households of HBsAg carriers as well as immigrants, remain a priority for the future.

Hepatitis B vaccine effectiveness in the face of global HBV genotype diversity

Recombinant hepatitis B vaccines are of the A2 genotype; one of ten known genotypes whose distribution varies globally. Reports of rare HBV infections in blood donors with an imbalance of non-A2 genotype HBV in vaccinated subjects have raised questions about the cross-protection afforded by HBV-A2 vaccines. Infections in HBV vaccinees were asymptomatic and transient, indicating that vaccination prevented clinical disease. Preclinical data demonstrate cross-reactivity and cross-protection by A2 vaccines against non-A2 HBV genotypes. Substantial improvements in HBV control have been demonstrated in countries with diverse genotype distribution that have introduced universal childhood HBV vaccination programs. Available data show that current HBV-A2 vaccines are highly effective in preventing infections and clinical disease caused by all known HBV genotypes.

Global epidemiology of hepatitis B virus infection: new estimates of age-specific HBsAg seroprevalence and endemicity

OBJECTIVE

Chronic hepatitis B virus infection is one of the most serious infections and a major risk factor for deaths from cirrhosis and liver cancer. We estimate age-, sex- and region-specific prevalence of chronic HBV infection and calculate the absolute number of persons being chronically infected.

METHODS

A systematic review of the literature for studies reporting HBV infection was conducted and worldwide HBsAg seroprevalence data was collected over a 27-year period (1980-2007). Based on observed data, age-specific prevalence and endemicity were estimated on a global level and for all world regions for 1990 and 2005 using an empirical Bayesian hierarchical model.

FINDINGS

From 1990 to 2005, the prevalence of chronic HBV infection decreased in most regions. This was particularly evident in Central sub-Saharan Africa, Tropical and Central Latin America, South East Asia and Central Europe. Despite this decrease in prevalence, the absolute number of HBsAg positive persons increased from 223 million in 1990 to 240 million in 2005. Age-specific prevalence varied by geographical region with highest endemicity levels in sub-Saharan Africa and prevalence below 2% in regions such as Tropical and Central Latin America, North America and Western Europe. Asian regions showed distinct prevalence patterns with lower intermediate prevalence in South Asia, but up to 8.6% HBsAg prevalence in East Asia. Strong declines were seen in South East Asian children.

CONCLUSION

Declines in HBV infection prevalence may be related to expanded immunization. The increasing overall number of individuals being chronically infected with HBV, and the widespread global differences in HBV prevalence call for targeted approaches to tackle HBV-related mortality and morbidity. HBV infection prevalence data are needed at country and sub-national level to estimate disease burden and guide health and vaccine policy.

Emergence of HBV resistance to lamivudine (3TC) in HIV/HBV co-infected patients in The Gambia, West Africa

BACKGROUND

Lamivudine (3TC) is a potent inhibitor of both Hepatitis B virus (HBV) and Human Immunodeficiency Virus (HIV) replication and is part of first-line highly active antiretroviral therapy (HAART) in the Gambia. Unfortunately, the effectiveness of 3TC against HBV is limited by the emergence of resistant strains.

AIM

The aim of this retrospective study was to characterise 3TC-resistant mutations in HBV from co-infected patients receiving HAART, by generating HBV polymerase sequence data and viral loads from HBV genotype E infected patients, both at initiation and during a course of 3TC therapy.

METHOD

Samples from 21 HBV chronic carriers co-infected with HIV-1 (n = 18), HIV-2 (n = 2) and HIV-dual (n = 1) receiving HAART for a period of 6-52 months were analysed for the emergence of 3TC-resistance mutations.

FINDINGS

Sixteen out of 21 HBV/HIV co-infected patients responded well to HAART treatment maintaining suppression of HBV viraemia to low (≤ 104 copies/mL) (n = 5) or undetectable levels (< 260 copies/ml) (n = 11). Out of the 5 non-responders, 3 had developed 3TC-resistant HBV strains showing mutations in the YMDD motif at position 204 of the RT domain of the HBV polymerase. One patient showed the M204V+ L180M+ V173L+ triple mutation associated with a vaccine escape phenotype, which could be of public health concern in a country with a national HBV vaccination programme. All except one patient was infected with HBV genotype E.

CONCLUSIONS

Our findings confirm the risk of 3TC mutations in HAART patients following monotherapy. This is a novel study on 3TC resistance in HBV genotype E patients and encourage the use of tenofovir (in association with 3TC), which has not shown unequivocally documented HBV resistance to date, as part of first-line therapy in HIV/HBV co-infected patients in West Africa.HBV- hepatitis B infection; HIV- human immunodeficiency virus; HAART- antiretroviral therapy.

HBV vaccine efficacy and detection and genotyping of vaccineé asymptomatic breakthrough HBV infection in Egypt

AIM

To evaluate the impact of mass vaccination against the hepatitis B virus (HBV) in Egypt, and to search for vaccinee asymptomatic breakthrough HBV infection and its genotype.

METHODS

Seven hundred serum samples from vaccinated children and adults (aged 2-47 years) were used for quantitative and qualitative detection of HBsAb by ELISA. Three hundred and sixty serum samples representing undetectable or low or high HBsAb were screened for markers of active HBV infection (HBsAg, HBcAb (IgG) and HBeAb by ELISA, plus HBsAg by AxSYM) and HBV-DNA genotyping by nested multiplex PCR and by DNA sequencing.

RESULTS

It was found that 65% of children aged 2-4 years, and 20.5% aged 4-13 years, as well as 45% adults were good responders to HBV vaccination mounting protective level HBsAb. Poor responders were 28%, 59.5% and 34%, and non-responders were 7%, 20% and 21% respectively, in the three studied groups. Markers of asymptomatic HBV infections were HBsAg detected by ELISA in 2.5% vs 11.39% by AxSYM. Other markers were HBcAb (IgG) in 1.38%, HBeAb in 0.83%, and HBV-DNA in 7.8%. All had HBV genotype E infection.

CONCLUSION

It is concluded that HBV vaccine is efficient in controlling HBV infection among children and adults. The vaccine breakthrough infection was by HBV genotype E. A booster dose of vaccine is recommended, probably four years after initial vaccination.

Preventing primary liver cancer: the HBV vaccination project in the Gambia (West Africa)

The Gambia Hepatitis Intervention Study (GHIS) consisted in the progressive introduction of HBV plasma-derived vaccine in different zones of this African country during the period 1986-1990. The study was launched and coordinated by IARC and is one of the most effective examples of an intervention project that both substantially contributed to our knowledge and to the health of local populations. Similar intervention studies have been carried out in South-East Asia. The studies indicate that the natural history of HBV infection differs in different populations , having a direct relevance for the implementation of HBV vaccination programmes in various parts of the world.

Partially randomized, non-blinded trial of DNA and MVA therapeutic vaccines based on hepatitis B virus surface protein for chronic HBV infection

BACKGROUND

Chronic HBV infects 350 million people causing cancer and liver failure. We aimed to assess the safety and efficacy of plasmid DNA (pSG2.HBs) vaccine, followed by recombinant modified vaccinia virus Ankara (MVA.HBs), encoding the surface antigen of HBV as therapy for chronic HBV. A secondary goal was to characterize the immune responses.

METHODS

Firstly 32 HBV e antigen negative (eAg(-)) participants were randomly assigned to one of four groups: to receive vaccines alone, lamivudine (3TC) alone, both, or neither. Later 16 eAg(+) volunteers in two groups received either 3TC alone or both 3TC and vaccines. Finally, 12 eAg(-) and 12 eAg(+) subjects were enrolled into higher-dose treatment groups. Healthy but chronically HBV-infected males between the ages of 15-25 who lived in the western part of The Gambia were eligible. Participants in some groups received 1 mg or 2 mg of pSG2.HBs intramuscularly twice followed by 5×10(7) pfu or 1.5×10(8) pfu of MVA.HBs intradermally at 3-weekly intervals with or without concomitant 3TC for 11-14 weeks. Intradermal rabies vaccine was administered to a negative control group. Safety was assessed clinically and biochemically. The primary measure of efficacy was a quantitative PCR assay of plasma HBV. Immunity was assessed by IFN-γ ELISpot and intracellular cytokine staining.

RESULTS

Mild local and systemic adverse events were observed following the vaccines. A small shiny scar was observed in some cases after MVA.HBs. There were no significant changes in AST or ALT. HBeAg was lost in one participant in the higher-dose group. As expected, the 3TC therapy reduced viraemia levels during therapy, but the prime-boost vaccine regimen did not reduce the viraemia. The immune responses were variable. The majority of IFN-γ was made by antigen non-specific CD16(+) cells (both CD3(+) and CD3(-)).

CONCLUSIONS

The vaccines were well tolerated but did not control HBV infection.

TRIAL REGISTRATION

ISRCTN ISRCTN67270384.

The worldwide impact of vaccination on the control and protection of viral hepatitis B

Viral hepatitis B is a leading cause of acute and chronic liver disease worldwide, including cirrhosis and hepatocellular carcinoma. Vaccination is the most effective measure for controlling and preventing hepatitis B and its severe long-term sequelae. According to the World Health Organization (WHO), by the end of 2008 177 countries had introduced hepatitis B vaccination into their national routine neonatal, infant and/or adolescent immunisation programmes, and Italy was one of the first countries to implement a universal strategy of hepatitis B vaccination. The implementation of such vaccination programmes has globally resulted in a marked decrease in disease burden, in the carrier rate and in hepatitis B-related morbidity and mortality. Despite this success, work remains to be done to fully achieve the WHO goal of control of hepatitis B and HBV-related diseases on a global scale.

Epidemiological changes in hepatitis B prevalence in an entire population after 20 years of the universal HBV vaccination programme

A universal hepatitis B vaccination programme has been conducted in Long An county since 1986. To investigate the epidemiological changes in hepatitis B virus (HBV) infection we conducted a serosurvey there in 2005. A total of 4686 subjects were enrolled and vaccination history and blood samples collected. HBV infective markers were determined by radioimmunoassay. The results were compared with the data of 1985. Our results show that the overall HBsAg prevalence was 7·5%, less than half of the prevalence reported in 1985. HBsAg and anti-HBc antibody prevalence in people born after 1985 decreased markedly. The gender difference in HBsAg prevalence was abolished in subjects aged <20 years. The administration of a first dose of vaccine within 24 h could reduce the HBsAg prevalence by half. In conclusion, the marked epidemiological changes in HBV prevalence found in this serosurvey indicate that the implementation of HBV vaccination was highly successful.

Control of hepatocellular carcinoma through hepatitis B vaccination in areas of high endemicity: perspectives for global liver cancer prevention

There are approximately 360 millions chronic carriers of Hepatitis B virus worldwide. Patterns of HB carriage are variable from one region to the other. Regions with rates of carriage over 8% are commonly considered as "high endemicity" regions. HB carriers have a very significant lifetime risk of developing chronic liver diseases such as cirrhosis and/or liver cancer (hepatocellular carcinoma, HCC). An efficient HB vaccine is available since the early eighties and has been used since for universal infant vaccination in regions of high endemicity. Observations from Taiwan, where universal infant vaccination was introduced from 1984, show a remarkable, long-lasting protection against carriage and reduction of HCC rates in adolescent and young adults born after the initiation of the programme. Two population-based trials have been set up in the mid-eighties to evaluate lifelong protective effects of infant HB vaccine against liver cancer, in The Gambia (West Africa) and in the area of Qidong, China. In other high-endemicity regions of Asia and Africa, universal infants vaccination has consistently showed a long-lasting high protection against chronic carriage and this is expected to lead to a dramatic decrease of chronic liver disease and liver cancer within the next decades. Here we briefly review the lessons of vaccination programmes and trials in high-endemicity regions, based on data gathered during 15-20years of implementation.

Immunogenicity and immunologic memory after hepatitis B virus booster vaccination in HIV-infected children receiving highly active antiretroviral therapy

BACKGROUND

Hepatitis B virus (HBV) is an important cause of comorbidity in human immunodeficiency virus (HIV)-infected individuals. The immunogenicity of HBV vaccination in children receiving highly active antiretroviral therapy (HAART) was investigated.

METHODS

HIV-infected children receiving HAART who had low to moderate HIV loads and who had previously received 3 doses of HBV vaccine were given an HBV vaccine booster. Concentrations of antibody to hepatitis B surface antigen (anti-HBs) were determined before vaccination and at weeks 8, 48, and 96. A subset of subjects was administered a subsequent dose, and anti-HBs was measured before and 1 and 4 weeks later.

RESULTS

At entry, 24% of 204 subjects were seropositive. Vaccine response occurred in 46% on the basis of seropositivity 8 weeks after vaccination and in 37% on the basis of a 4-fold rise in antibody concentration. Of 69 subjects given another vaccination 4-5 years later, immunologic memory was exhibited by 45% on the basis of seropositivity 1 week after vaccination and by 29% on the basis of a 4-fold rise in antibody concentration at 1 week. Predictors of response and memory included higher nadir and current CD4 cell percentage, higher CD19 cell percentage, and undetectable HIV load.

CONCLUSIONS

HIV-infected children frequently lack protective levels of anti-HBs after previous HBV vaccination, and a significant proportion of them do not respond to booster vaccination or demonstrate memory despite receiving HAART, leaving this population insufficiently protected from infection with HBV.

Gastroenterology in developing countries: issues and advances

Developing countries shoulder a considerable burden of gastroenterological disease. Infectious diseases in particular cause enormous morbidity and mortality. Diseases which afflict both western and developing countries are often seen in more florid forms in poorer countries. Innovative techniques continuously improve and update gastroenterological practice. However, advances in diagnosis and treatment which are commonplace in the West, have yet to reach many developing countries. Clinical guidelines, based on these advances and collated in resource-rich environments, lose their relevance outside these settings. In this two-part review, we first highlight the global burden of gastroenterological disease in three major areas: diarrhoeal diseases, hepatitis B, and Helicobacter pylori. Recent progress in their management is explored, with consideration of future solutions. The second part of the review focuses on the delivery of clinical services in developing countries. Inadequate numbers of healthcare workers hamper efforts to combat gastroenterological disease. Reasons for this shortage are examined, along with possibilities for increased specialist training. Endoscopy services, the mainstay of gastroenterology in the West, are in their infancy in many developing countries. The challenges faced by those setting up a service are illustrated by the example of a Nigerian endoscopy unit. Finally, we highlight the limited scope of many clinical guidelines produced in western countries. Guidelines which take account of resource limitations in the form of "cascades" are advocated in order to make these guidelines truly global. Recognition of the different working conditions facing practitioners worldwide is an important step towards narrowing the gap between gastroenterology in rich and poor countries.

Epidemiology and prevention of hepatocellular carcinoma

A meta-analysis on the seroprevalence of hepatitis B surface antigen (HBsAg) and antibodies against hepatitis C virus (anti-HCV) in 27881 hepatocellular carcinomas from 90 studies confirmed wide international variations. A predominance of HBsAg was found in hepatocellular carcinomas from most Asian, African and Latin American countries, but anti-HCV predominated in Europe, North America, Japan, Pakistan, Mongolia, and Egypt. Anti-HCV was found more often than HBsAg in Europe and the United States. Twenty-five years after having been licensed, HBV vaccination programmes are now carried out in 158 countries, but they have yet to reach many high-risk populations in sub-Saharan Africa and Asia. In the absence of a vaccine, the prevention of HCV infection requires an integrated strategy (i.e., screening of blood donations, safe injection practices, and avoidance of unnecessary injections).