Benefits of early hepatitis B immunization programs for newborns and infants

The Global Impact of Hepatitis B Vaccination on Hepatocellular Carcinoma

Over 1.5 million preventable new hepatitis B infections continue to occur each year and there are an estimated 296 million people living with chronic hepatitis B infection worldwide, resulting in more than 820,000 deaths annually due to liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis B vaccination remains the cornerstone of public health policy to prevent HCC and a vital component of the global hepatitis B elimination response. The WHO has set a 90% vaccination target to achieve hepatitis B elimination by 2030; however, there is wide variability in reported birth dose coverage, with global coverage at only 42%. In this review, we outline the global trends in hepatitis B vaccination coverage and the impact of hepatitis B vaccination on HCC incidence and discuss the challenges and enabling factors for achieving WHO 2030 hepatitis B vaccination coverage targets.

Susceptibility to Vaccine-Preventable Diseases in Four Districts of Xaysomboun Province, Lao People’s Democratic Republic

Xaysomboun province has some of the lowest health indicators in Lao People’s Democratic Republic (PDR). This cross-sectional study aimed to determine the vaccination, susceptibility and exposure status of the population to hepatitis B virus (HBV), measles, rubella, and tetanus. Participants aged 5 years and older were randomly selected from four districts. From each enrolled participant, demographic data and 5 mL of blood sample were taken. HBV surface antigen (HBsAg) and antibodies against HBV, measles, rubella, and tetanus were detected by ELISA. A total of 363 participants (age 5 to 80 years) were included. HBV exposure, as determined by anti-HBV core (anti-HBc) antibodies, was 56.2% overall, and was significantly higher among those aged ≥21 years (78.1%). HBsAg was detected in 9.4% overall and increased to 20% in ages 31–40 years. Only 13.8% of participants had serology indicative of vaccination (anti-HBs positive, anti-HBc negative). Seroprotection against measles was 74.6% overall but only 41.7% in children aged 5–10 years. Anti-rubella IgG was 94.2% overall and high in all age groups. Tetanus seroprevalence was only 47.4% overall but significantly higher in females aged 31–40 (75.6%). We suggest strengthening of routine and booster HBV, measles, and tetanus vaccine coverage in Xaysomboun province.

Clinical Protocol for a Longitudinal Cohort Study Employing Systems Biology to Identify Markers of Vaccine Immunogenicity in Newborn Infants in The Gambia and Papua New Guinea

Background: Infection contributes to significant morbidity and mortality particularly in the very young and in low- and middle-income countries. While vaccines are a highly cost-effective tool against infectious disease little is known regarding the cellular and molecular pathways by which vaccines induce protection at an early age. Immunity is distinct in early life and greater precision is required in our understanding of mechanisms of early life protection to inform development of new pediatric vaccines. Methods and Analysis: We will apply transcriptomic, proteomic, metabolomic, multiplex cytokine/chemokine, adenosine deaminase, and flow cytometry immune cell phenotyping to delineate early cellular and molecular signatures that correspond to vaccine immunogenicity. This approach will be applied to a neonatal cohort in The Gambia (N ~ 720) receiving at birth: (1) Hepatitis B (HepB) vaccine alone, (2) Bacille Calmette Guerin (BCG) vaccine alone, or (3) HepB and BCG vaccines, (4) HepB and BCG vaccines delayed till day 10 at the latest. Each study participant will have a baseline peripheral blood sample drawn at DOL0 and a second blood sample at DOL1,-3, or-7 as well as late timepoints to assess HepB vaccine immunogenicity. Blood will be fractionated via a "small sample big data" standard operating procedure that enables multiple downstream systems biology assays. We will apply both univariate and multivariate frameworks and multi-OMIC data integration to identify features associated with anti-Hepatitis B (anti-HB) titer, an established correlate of protection. Cord blood sample collection from a subset of participants will enable human in vitro modeling to test mechanistic hypotheses identified in silico regarding vaccine action. Maternal anti-HB titer and the infant microbiome will also be correlated with our findings which will be validated in a smaller cohort in Papua New Guinea (N ~ 80). Ethics and Dissemination: The study has been approved by The Gambia Government/MRCG Joint Ethics Committee and The Boston Children's Hospital Institutional Review Board. Ethics review is ongoing with the Papua New Guinea Medical Research Advisory Committee. All de-identified data will be uploaded to public repositories following submission of study output for publication. Feedback meetings will be organized to disseminate output to the study communities. Clinical Trial Registration: Clinicaltrials.gov Registration Number: NCT03246230.

Study on Status and Willingness towards Hepatitis B Vaccination among Migrant Workers in Chongqing, China: A Cross-Sectional Study

Background: Rural-to-urban migrant workers may serve as a bridge population for the cross-regional spread of hepatitis B vaccination (HBV) due to frequent shifts between their work areas and homelands, and they are less likely to be covered by the national hepatitis B (HB) immunization program. This study aimed to investigate the current inoculation status of HB vaccine among migrant workers and the willingness to be vaccinated among non-vaccinated ones. Methods: We conducted a cross-sectional survey using anonymous interviews with migrant workers selected by two-stage cluster sampling from July to December 2018. Binary logistic regression models were adopted to detect influencing factors associated with HB inoculation status and vaccination willingness. Results: 1574 respondents were recruited in the surveys, and 773 (49.11%) respondents reported that they had been inoculated with HB vaccine. Only 285 (35.58%) non-vaccinated respondents were willing to be inoculated. Logistic regression indicated that younger age, higher education level, less wearing of condoms, higher knowledge scores of HB, and higher risk perception of HBV infection were positively associated with inoculation of HB vaccine. Respondents who were more highly educated, and drinkers, with higher knowledge scores of HB and with higher risk perception of HBV infection were more willing to be vaccinated. Conclusions: the HB vaccination rate of migrant workers in Chongqing was relatively low and only a small section of non-vaccinated migrant workers had vaccination willingness. Health interventions and policies are needed to improve knowledge and cognition of HB among migrant workers, particularly for those who are older, less educated, poor in HB knowledge, less likely to wear condoms, and non-drinkers. Peer education, as well as the combination of traditional and new media, would be accessible and effective ways to disseminate HB related knowledge for migrant workers.

24 year outcomes of hepatitis B vaccination in Hangzhou, China

To evaluate the impact of the universal infant HepB vaccination program on hepatitis B virus infection in Hangzhou, China. Hepatitis B incidences and HepB vaccination rates of Hangzhou from 1990 to 2003 were acquired from the historical paper-documents, while which were derived from China Information System for Diseases Control and Prevention and Zhejiang Information System for Immunization Program respectively from 2004 to 2013. A serology survey among person aged 0-59 y was conducted in Hangzhou in 2006. Participants were selected by stratified, multi-stage random sampling. Serum specimens were tested for HBsAg, anti-HBs , anti-HBc , HBeAg and anti-HBe by ELISA. For the past 24 years, hepatitis B incidence and mortality of Hangzhou declined dramatically (χ(2) = 3.2 × 10(4); χ(2) = 172.443; both P for trend < 0.001). Both urban and rural incidence descended (χ(2)urban = 1.904 × 10(4); χ(2)rural = 1.633 × 10(4) ; both P for trend < 0.001).Hepatitis B patients mainly concentrated in 20-40 y old; workers and farmers were the main infection occupations, which was varies in different years (χ(2) = 1.619 × 10(3), P < 0.001). Significant association was found between incidence of hepatitis B and HepB vaccination rate (r = 0 .946, χ(2) = 11.813, Pfor trend = 0.001). A total of 5605 participants aged 0-59 y included in this serological survey. The prevalence of HBsAg, anti-HBs, anti-HBc, HBeAg and anti-HBe were 6.19%, 45.83%, 57.25%, 0.62%, and 4.37%, respectively. Hangzhou has successfully integrated the HepB into routine immunization programs and this has had a significant impact on decreasing the incidence of hepatitis B infection.

Prevention of materno-foetal transmission of hepatitis B in sub-Saharan Africa: the evidence, current practice and future challenges

Hepatitis B (HBV) infection is highly endemic in sub-Saharan Africa (SSA), where more than 8% of the population remain chronic HBV carriers. SSA has one of the highest HBV-related liver cancer rates in the world (CA Cancer J Clin, 55, 2005, 74) and HBV-related liver cancer is the most common cause of premature death in West Africa (Lancet Oncol, 9, 2008, 683; Hepatology, 39, 2004, 211). As such, HBV represents a significant global threat to health in the African continent. Most SSA countries have elected to vaccinate all children against HBV through the WHO-sponsored Expanded Program of Immunization and the current recommendation from WHO-AFRO is for birth-dose HBV vaccination to prevent maternal/child transmission (MFT) and early horizontal transmission of HBV. However, in Africa, HBV vaccine coverage remains low and HBV birth-dose vaccination has not been implemented. HBV transmission from mother to child in the early perinatal period therefore remains a significant contributor to the burden of HBV-related disease in SSA. This review explores the evidence for materno-foetal transmission of HBV in SSA, outlining current practice for HBV MFT prevention and identifying the significant challenges to implementation of HBV prevention in SSA.

Prevalence of hepatitis B virus seromarkers in young adults vaccinated at birth; impact on the epidemiology of hepatitis B infection in iran

BACKGROUND

The epidemiological impact and the duration of protection provided by infant hepatitis B (HB) vaccination are unknown.

OBJECTIVES

This study was designed to determine the hepatitis B virus (HBV) infection seromarkers in young adults who have been vaccinated against HBV as the first group of Iranian neonates during 1993 and 1994.

PATIENTS AND METHODS

We recruited 510 young adults with a history of complete HB vaccination at birth. HBV seromarkers (HB surface antigen (HBs Ag), antibody against HBs Ag (Anti-HBs), and antibody against HB core antigen (Anti-HBc) were measured using ELISA method. Anti-HBs titers ≥ 10 IU/L were considered protective and titers more than 300 IU/L were indicative of a natural boosting. Positive results for Anti-HBc and HBs Ag were considered as breakthrough infection and possible vaccine failure, respectively. The history of acute symptomatic clinical hepatitis was also investigated.

RESULTS

Anti-HBs seropositivity rate was detected in 224 of 510 [95% CI: 39-47] young adults. Breakthrough infection (positive sera for Anti-HBc without chronic infection) was observed in 18 [95% CI: 2.5-3.5] subjects. There were neither HBs Ag positive results nor symptomatic hepatitis cases.

CONCLUSIONS

The study results indicated that the neonatal HBV immunization induced a long-term protection against HBV and was very efficacious in reducing chronic HBV infection rate in vaccinated young adults in Iran.

Immune memory to hepatitis B persists in children aged 7-8 years, who were vaccinated in infancy with 4 doses of hexavalent DTPa-HBV-IPV/Hib (Infanrix™ hexa) vaccine

Protection against hepatitis B disease relies on either protective serum antibodies or on the ability of the immune system to mount an anamnestic response when confronted with the hepatitis B virus (HBV). This open multicenter study (EUDRACT: 2010-022538-10) measured antibodies to HBV surface antigen (anti-HBs) in 7-8-year-old children who had received 4 doses of hexavalent diphtheria-tetanus-acellular pertussis-HBV-inactivated poliovirus-Hemophilus influenzae type b conjugate vaccine (DTPa-HBV-IPV/Hib: Infanrix™ hexa; GlaxoSmithKline Vaccines) in the first 2 years of life through routine vaccine services in Germany. The ability of these children to mount an anamnestic response to a challenge dose of monovalent HBV vaccine (Engerix™ B Kinder; GlaxoSmithKline Vaccines) was also assessed. Before the challenge dose, 78.5% of children had anti-HBs levels ≥6.2 mIU/mL (seropositive) and 72.2% had anti-HBs levels ≥10 mIU/mL (seroprotected). Post-challenge, 98.9% had anti-HBs levels ≥10 mIU/mL and 95.8% had anti-HBs ≥100 mIU/mL. An anamnestic response to the challenge was observed in 96.6% of all subjects. The challenge dose was well tolerated, with a reactogenicity and safety profile consistent with published data. DTPa-HBV-IPV/Hib induces long-lasting immune memory to HBV that appears very similar to that induced by monovalent HBV vaccines. Protection against hepatitis B may be conferred through immune memory in subjects who responded to primary vaccination, even when they subsequently lose detectable levels of circulating anti-HBs antibodies.

Hepatitis B immunity in teenagers vaccinated as infants: an Italian 17-year follow-up study

We assessed the persistence of hepatitis B surface antigen antibody (anti-HBs) and immune memory in a cohort of 571 teenagers vaccinated against hepatitis B as infants, 17 years earlier. Vaccinees were followed-up in 2003 and in 2010 (i.e. 10 years and 17 years after primary vaccination, respectively). When tested in 2003, 199 vaccinees (group A) had anti-HBs <10 mIU/mL and were boosted, 372 (group B) were not boosted because they had anti-HBs ≥10 mIU/mL (n = 344) or refused booster (n = 28) despite anti-HBs <10 mIU/mL. In 2010, 72.9% (416/571) of participants had anti-HBs ≥10 mIU/mL (67.3% in group A vs. 75.8% in group B; p 0.03). The geometric mean concentrations (GMCs) were similar in both groups. Between 2003 and 2010, anti-HBs concentrations in previously boosted individuals markedly declined with GMC dropping from 486 to 27.7 mIU/mL (p <0.001). Fifteen vaccinees showed a marked increase of antibody, possibly due to natural booster. In 2010, 96 individuals (37 of group A and 59 of group B) with anti-HBs <10 mIU/mL were boosted; all vaccinees of the former group and all but two of the latter had an anamnestic response. Post-booster GMC was higher in group B (895.6 vs. 492.2 mIU/mL; p 0.039). This finding shows that the immune memory for HBsAg persists beyond the time at which anti-HBs disappears, conferring long-term protection.

Inflammatory responses to hepatitis B virus vaccine in healthy term infants

Hepatitis B virus (HBV) infection continues to be a serious global health problem. During the course of HBV vaccination, we observed C-reactive protein (CRP) elevation in term infants without sepsis. Therefore, we prospectively studied interleukin-6 (IL-6) and CRP responses to HBV immunization. In 70 healthy term infants without signs and symptoms of sepsis and sepsis risk factors, IL-6, CRP, and white blood cell count levels were determined before and 24 h after immunization. Significant increases in CRP levels were seen 24 h after vaccination (p < 0.001). Although CRP levels of 22 infants at second evaluation were above the cutoff level for sepsis (4.82 mg/L), they had no clinical signs and symptoms of sepsis. After 48-72 h, CRP levels of these infants returned to normal levels with no blood culture positivity.

CONCLUSION

our study showed that HBV vaccine is responsible for CRP elevation in term infants after vaccination at birth. To the best of our knowledge, this is the first study evaluating CRP response to HBV vaccine at birth in term infants. We suggest that this response should be considered in differentiation of early neonatal sepsis to avoid unnecessary antibiotic use.

Risk factors for HIV, viral hepatitis, and syphilis among heroin users in northern Taiwan

A total of 125 heroin users were recruited from a detention center and two psychiatric hospitals in northern Taiwan during 2006 in order to investigate the prevalence and correlates of blood-borne infections among heroin users. The seroprevalence rates of the human immunodeficiency virus (HIV), hepatitis C virus (HCV), HBV, HDV, and syphilis were 15.2%, 74.4%, 15.2%, 6.4%, and 8%, respectively. Injection risk behaviors were associated with HIV, HCV, and syphilis infections, but not with HBV infections. Meanwhile, HCV and HBV infections were correlated with the duration of heroin use and age of the subjects, respectively. The results of this study suggest that a comprehensive public health program is needed to prevent transmission of these blood-borne infections. The study's limitations are noted.

Associated factors for recommending HBV vaccination to children among Georgian health care workers

Background

Most cases of hepatitis B virus (HBV) infection and subsequent liver diseases can be prevented with universal newborn HBV vaccination. The attitudes of health care workers about HBV vaccination and their willingness to recommend vaccine have been shown to impact HBV vaccination coverage and the prevention of vertical transmission of HBV. The purpose of this study was to ascertain the factors associated with health care worker recommendations regarding newborn HBV vaccination.

Methods

A cross-sectional study of prevalence and awareness of hepatitis B and hepatitis B vaccine was conducted among randomly selected physicians and nurses employed in seven hospitals in Georgia in 2006 and 2007. Self-administered questionnaires included a module on recommendations for HBV, HCV and HIV.

Results

Of the 1328 participants included in this analysis, 36% reported recommending against hepatitis B vaccination for children, including 33% of paediatricians. Among the 70.6% who provided a reason for not recommending HBV vaccine, the most common concern was an adverse vaccine event. Unvaccinated physicians and nurses were more likely to recommend against HBV vaccine (40.4% vs 11.4%, PR 3.54; 95% CI: 2.38, 5.29). Additionally, health care worker age was inversely correlated with recommendations for HBV vaccine with older workers less likely to recommend it.

Conclusion

Vaccinating health care workers against HBV may provide a dual benefit by boosting occupational safety as well as strengthening universal coverage programs for newborns.

Epidemiological pattern of hepatitis B and hepatitis C as etiological agents for hepatocellular carcinoma in iran and worldwide

CONTEXT

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections constitute a major global health problem. About 60,000 and 350,000 deaths occur as the results of HBV and HCV infections, respectively. Chronic hepatitis B and C infections are leading causes of cirrhosis and hepatocellular carcinoma (HCC) which are considered as the third cancer-associated cause of deaths worldwide. Iran suffers from the same problem but to a lesser extent as it is considered as a low endemic area for HBV and HCV infections and also as a low incidence area of HCC. This study was conducted to assess and provide a clear picture about epidemiology of HBV and HCV infections in Iran and worldwide, with the consequence on HCC distribution all over the world including Iran, and to analyze current literature regarding the modes of transmission and risk factors of HBV and HCV infections.

EVIDENCE ACQUISITION

In this review, we performed electronic and manual searches on available databases such as MEDLINE, PubMed, Ovid, Embase, and the Iranian databases such as IranMedex. We also performed a Google search to find related articles.

RESULTS

HBV and HCV infections are the most common risk factors of hepatocellular carcinoma. The epidemiology of HCC usually follows that of HBV and HCV infections. With the introduction of HBV national vaccine in Iran and worldwide, there is a noticeable effect on reduction in HBV prevalence in most countries, and we expect that HCV will replace HBV as a major risk factor of HCC in Iran and worldwide. Alcohol plays a minor role as a risk factor for cirrhosis and HCC in Iran, Asia, and Africa, despite its noticeable role in Europe and the USA.

CONCLUSIONS

Vaccination against HBV remains the most effective approach against HBV infection with consequence decrease in HBV-related HCC. There is a need to improve the awareness about epidemiology of HBV and HCV infections, modes of transmission, and their complications, specifically HCC among population.

Efficacy of yeast-derived recombinant hepatitis B vaccine after being used for 12 years in highly endemic areas in China

OBJECTIVE

To evaluate the long-term efficacy and duration of yeast-derived recombinant hepatitis B vaccine in hepatitis B virus (HBV)-endemic areas.

METHOD

A cross-sectional investigation was carried out in five HBV-endemic areas. Children who were born between 1997 and 2008 and vaccinated with yeast-derived recombinant hepatitis B vaccine were selected. Serum samples were taken to test HBV infection markers by microparticle enzyme immunoassay, and the results were compared to those before vaccination.

RESULTS

7066 subjects were enrolled. The average adjusted hepatitis B surface antigen (HBsAg) prevalence was 1.02%. HBV core antibody (anti-HBc) prevalence was 3.54%. The overall percentage of HBsAg(-)&Anti-HBc(-)&Anti-HBs(+) was 61.34%. With time after immunization, the percentage annually decreases from 86.11% in 2008 to 49.80% in 1997. Geometric mean concentration (GMC) of anti-HBs decreased significantly annually. The portion of GMC=100-999.9 mIU/ml was 48.0% in 2008, and decreased to 16.7% in 1997.

CONCLUSION

HBsAg prevalence decreased dramatically. This shows that the yeast-derived recombinant hepatitis B vaccine is effective and stable after being used for 12 years in HBV-endemic areas. It is not suggested to carry out booster immunization.

Changing epidemiology of hepatitis B and migration--a comparison of six Northern and North-Western European countries

BACKGROUND

Increased migration volume and different Hepatitis B prevalence between immigration and emigration countries have changed the Hepatitis B virus (HBV) epidemiology considerably in Northern and North-Western European migrants-receiving countries. Due to the difference in migration status monitoring, the HBV infection data on migrants are not easily comparable among those countries. The study aims were: to compare the migration status indicators used by the national surveillance system in six Northern and North-Western European countries (the Netherlands, Germany, Finland, Denmark, Sweden and the UK); to determine the impact of the migration status on HBV infection by comparing the available data on prevalence and transmission routes of Hepatitis B in the migration and the general population in the six countries; to recommend sensible indicators and pertinent measures for HBV infection surveillance and control in the region.

METHODS

Literature review, statistical data analysis on migration and HBV infection in the six countries; expert interviews to identify migration status indicators used in national surveillance systems.

RESULTS

Evident differences were found between the migration and the general population in Hepatitis B prevalence and transmission routes in the six countries. Migration status is monitored differently in six surveillance systems; immigrants from high/intermediate Hepatitis B endemic countries constitute a substantial proportion of HBsAg(+) and chronic cases in all six countries.

CONCLUSIONS

International migration has an obvious impact on Hepatitis B prevalence in the six countries. It is important to include common migration status indicators and to collect comparable data for HBV infection surveillance in different notification systems.

Development of newborn and infant vaccines

Vaccines for early-life immunization are a crucial biomedical intervention to reduce global morbidity and mortality, yet their developmental path has been largely ad hoc, empiric, and inconsistent. Immune responses of human newborns and infants are distinct and cannot be predicted from those of human adults or animal models. Therefore, understanding and modeling age-specific human immune responses will be vital to the rational design and development of safe and effective vaccines for newborns and infants.

Factors influencing administration of hepatitis B vaccine to community-dwelling teenagers aged 12-18 with an intellectual disability

The study aims to determine hepatitis B vaccination coverage rates among community-dwelling teenagers with an intellectual disability in Taiwan and to identify the possible influencing factors of their vaccination. The present paper was part of the results of the "2007 National Survey on Healthy Behaviors and Preventive Health Utilizations of People with Intellectual Disabilities in Taiwan," which was a cross-sectional survey of 1111 intellectually disabled (ID) teenagers ranging from 12 to 18 years of age. The results showed that the completed hepatitis B vaccination rate was 72.9%, a rate lower than that in the general population of Taiwan considering the same age group. There was no gender difference between each age group in the vaccination rate in this population. Multilevel logistic regression analyses revealed that those ID individuals whose primary caregivers were parents or siblings (OR = 2.45, 95% CI = 1.29-4.64), whose household monthly income was 20,000-59,999 NTD vs. less than 20,000 NTD (OR = 2.47, 95% CI = 1.00-6.12), and who had ever undergone an oral health exam (OR = 2.29, 95% CI = 1.24-4.01) were more likely to receive a complete hepatitis B vaccination than their counterparts. The study highlighted that most teenagers had received complete hepatitis B vaccination. Nonetheless, better public health strategies may be needed to deliver the hepatitis B vaccine to those who do not comply with the vaccination schedule in the community.

Overview of the Clinical Consult Case Review of adverse events following immunization: Clinical Immunization Safety Assessment (CISA) network 2004-2009

BACKGROUND

In 2004 the Clinical Consult Case Review (CCCR) working group was formed within the CDC-funded Clinical Immunization Safety Assessment (CISA) Network to review individual cases of adverse events following immunizations (AEFI).

METHODS

Cases were referred by practitioners, health departments, or CDC employees. Vaccine Adverse Event Reporting System (VAERS) searches and literature reviews for similar cases were performed prior to review. After CCCR discussion, AEFI were assessed for a causal relationship with vaccination and recommendations regarding future immunizations were relayed back to the referring physicians. In 2010, surveys were sent to referring physicians to determine the utility and effectiveness of the CCCR service.

RESULTS

CISA investigators reviewed 76 cases during 68 conference calls between April 2004 and December 2009. Almost half of the cases (35/76) were neurological in nature. Similar AEFI for the specific vaccines received were discovered for 63 cases through VAERS searches and for 38 cases through PubMed searches. Causality assessment using the modified WHO criteria resulted in classifying 3 cases as definitely related to vaccine administration, 12 as probably related, 16 as possibly related, 18 as unlikely related, 10 as unrelated, and 17 had insufficient information to assign causality. The physician satisfaction survey was returned by 30 (57.7%) of those surveyed and a majority of respondents (93.3%) felt that the CCCR service was useful.

CONCLUSIONS

The CCCR provides advice about AEFI to practitioners, assigns potential causality, and contributes to an improved understanding of adverse health events following immunizations.

In vitro study on hepatitis B virus infecting human choriocarcinoma JEG3 cells and its mechanism

AIM

To build a hepatitis B virus (HBV)-infected human trophoblast cell model in vitro and determine the mechanism of intrauterine HBV infection.

METHODS

Serum from hepatitis B-infected patients containing HBV DNA >10(9) was drawn, subsequently inoculated into human trophoblast cells in vitro (JEG3) and passage-cultured. The supernatants and intracellular HBV viral load of inoculated cells were tested by real-time PCR, and HBV DNA was determined by Southern blot.

RESULTS

From inoculation of the 1st passage JEG3 cells, the supernatant viral load of the 1st passage was seen increasing over time, which peaked at 120 h, whereas the HBV viral load was seen decreasing gradually in subsequent passages, and tested negative after the 6th passage. In addition, infected cells of HBV DNA were tested by Southern blot, and showed continual expression in the subsequent cell passages 1-5 while passage 6 was negative. HBsAg was tested as positive from different passages 1-5, and its concentration was also seen decreasing with each subsequent passage cultured until the 6th passage when it tested negative.

CONCLUSION

HBV could infect human trophoblast cells (JEG3) in vitro, and it showed continual expression in subsequent cell passages 1-5.

Immunogenicity of recombinant hepatitis B vaccine: comparison of two different vaccination schedules

BACKGROUND

Neonatal immunization with hepatitis B (HB) vaccine induces protective levels of antibody (anti-HBs > or =10 IU/L) in a majority of vaccines. However, the duration of protection after HB vaccination in infants is unknown. A smaller proportion of children vaccinated beginning at birth with three doses of HB vaccine were found to have protective titers 5-10 years after initial vaccination. Long-term efficacy of HB vaccine depends mainly on peak antibody levels after vaccination, and subjects were observed to have lower levels of antibodies if they received the first dose of vaccine immediately after birth. The aim of our study was to compare the immunogenicity of two different HB vaccine schedules in infants born to HB surface antigen-negative mothers.

METHODS

Anti-HBs titers in infants vaccinated with two different schedules were compared. Infants were vaccinated at 0, 2, and 9 months (group 1) or at 2, 4, and 9 months (group 2). In total, 267 blood samples were analyzed at a mean of 14.20 +/- 2.39 months after the third vaccine dose. Sera were tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core antibody (anti-HBc) using commercial enzyme immunoassay kits.

RESULTS

The geometric mean titers for anti-HBs were 95.00 and 379.51 IU/L and the rates of anti-HBs more than > or =100 IU/L were 57.7 and 94.9% in group 1 and 2 infants, respectively.

CONCLUSION

Delaying the first dose of the HB vaccine until 2 months after birth produces a higher immune response and can provide longer term protection.

Hepatitis B virus DNA in saliva from children with chronic hepatitis B infection: implications for saliva as a potential mode of horizontal transmission

To explore the mechanism of horizontal transmission of hepatitis B virus (HBV) among children, we investigated the quantitative relationship between HBV in saliva and blood from 46 children with chronic hepatitis B. We found high levels of HBV DNA in saliva of HBeAg (+) children, suggesting saliva as a vehicle for horizontal transmission of HBV among children.

HEPATITIS B AND PREGNANCY, THE SCIENTIFIC BASIS FOR PERINATAL PREVENTION

Hepatitis B and its complications are one of the major global health problems. Around 2 billion individuals are infected by hepatitis B virus (HBV) worldwide, more than 350 million are chronically infected, and approximately 15 to 40 percents of them will develop serious complications such as liver cirrhosis, hepatic failure, or hepatocellular carcinoma (HCC). The worldwide prevalence of chronic HBV infection ranges from 0.1 to 20 percent and varies widely in different geographic areas. According to the prevalence rate, WHO has classified countries into 3 levels: high areas (>8%) such as Africa, Asia, Western Pacific and Middle East; intermediate areas (2–8%) such as South America and Eastern Europe, and low areas (<2%) such as Western Europe, North America, and Australia.

Evaluation of the compliance with recommended procedures in newborns exposed to HBsAg-positive mothers: a multicenter collaborative study

BACKGROUND

Maternal-infant transmission of hepatitis B virus (HBV) during birth carries a high risk for chronic HBV infection in infants with frequent subsequent development of chronic disease. This can be efficiently prevented by early immunization of exposed newborns. The purpose of this study was to determine the compliance with official recommendations for prevention of perinatal HBV transmission in hepatitis B surface antigen (HBsAg) exposed infants.

METHODS

Records of pregnant women at 4 sites in Switzerland, admitted for delivery in 2005 and 2006, were screened for maternal HBsAg testing. In HBsAg-exposed infants, recommended procedures (postnatal active and passive immunization, completion of immunization series, and serological success control) were checked.

RESULTS

Of 27,131 women tested for HBsAg, 194 (0.73%) were positive with 196 exposed neonates. Of these neonates, 143 (73%) were enrolled and 141 (99%) received simultaneous active and passive HBV immunization within 24 hours of birth. After discharge, the HBV immunization series was completed in 83%. Only 38% of children were tested for anti-HBs afterwards and protective antibody values (>100 U/L) were documented in 27% of the study cohort. No chronically infected child was identified. Analysis of hospital discharge letters revealed significant quality problems.

CONCLUSIONS

Intensified efforts are needed to improve the currently suboptimal medical care in HBsAg-exposed infants. We propose standardized discharge letters, as well as reminders to primary care physicians with precise instructions on the need to complete the immunization series in HBsAg-exposed infants and to evaluate success by determination of anti-HBs antibodies after the last dose.

Hepatitis B vaccination strategies tailored to different endemicity levels: some considerations

Hepatitis B is a serious public health problem. Worldwide three different levels of hepatitis B endemicity (high, intermediate and low) can be distinguished. Areas with different levels of endemicity require tailored vaccination strategies to fit the needs for individuals at risk and/or countries, depending on the infection risk per age group, vaccination rate, duration of protection after vaccination, cost effectiveness of vaccination strategies and ease of implementation in the national immunization schedules.This opinion paper evaluates these factors and proposes a combination of infant risk group and universal adolescent vaccination for low endemic countries thus targeting the different groups at risk. A universal infant vaccination schedule starting with a newborn vaccination within 24h after birth is more appropriate in intermediate- and high-endemic regions.

Review of 8 years of experience with Infanrix hexa (DTPa-HBV-IPV/Hib hexavalent vaccine)

Combination vaccines that include multiple antigens within one formulation are now widely accepted as an effective means of eliciting protection against several diseases at the same time. Owing to improvements in quality and convenient modes of administration, they have become part of routine pediatric practice. Hexavalent vaccines, including diphtheria, tetanus, pertussis, hepatitis B, polio and Haemophilus influenzae type b antigens represent the latest advance in the development of combination vaccines. Over 8 years since its first licensure, this review looks at the immunogenicity, efficacy and safety profile of the only hexavalent pediatric vaccine currently in use--Infanrix hexa (diphtheria, tetanus, acellular pertusis-hepatitis B virus-inactivated poliovirus vaccine/Haemophilus influenzae type b vaccine [DTPa-HBV-IPV/Hib]; GlaxoSmithKline Biologicals, Rixensart, Belgium)--through published clinical trials and postmarketing surveillance data. These data show DTPa-HBV-IPV/Hib to be highly immunogenic and well tolerated across a range of different primary and booster vaccination schedules, as well as when administered concomitantly with other licensed vaccines (e.g., pneumococcal conjugate vaccine). Additional issues surrounding the use of hexavalent vaccines are also reviewed.

Prevention of viral hepatitis (B and C) reassessed

As hepatitis B and C share modes of transmission, their combined occurrence is not uncommon, particularly in areas where both viruses are endemic and in individuals at high-risk of parenteral infection. Both viral hepatitis infections form an important global public health problem, responsible for over half a billion chronic infections worldwide. Their distinctive characteristics impact upon their epidemiology, transmission, and the success of the different prevention strategies. Since several decades a safe and effective vaccine has been available to prevent hepatitis B virus (HBV) infection. Universal vaccination is the cornerstone of global HBV control. Despite major success, vaccine uptake is hampered, and increasing efforts are required to eliminate acute and chronic hepatitis B. Unlike hepatitis C and HIV, HBV has not captured sufficient attention from policymakers, advocacy groups, or the general public: a major challenge for the future. Although progress has been made in the development of an hepatitis C vaccine, short-term successes are not expected. Even without a vaccine, successes can be reported in the field of hepatitis C due to e.g. implementation of universal precautionary measures in health-care settings, screening of blood and blood products, and identification and counselling of infected people. Despite important efforts, transmission in injecting drug users is increasing.