Hepatitis B vaccines: WHO position paper--recommendations. Vaccine. 2010;28:589-590. [PMID: 19896455 DOI: 10.1016/j.vaccine.2009.10.110]

Evaluation of factors associated with response to hepatitis B vaccination in patients with inflammatory bowel disease

It is recommended to investigate the serology of hepatitis B virus (HBV) and vaccinate seronegative patients at the time of diagnosis in inflammatory bowel diseases (IBD). This study aimed to investigate the efficacy of HBV vaccine and factors affecting the response.In this retrospective, observational study, HBV-seronegative IBD patients were administered 3 doses (at months 0, 1, and 6) recombinant 20  μg HbsAg. Patients' demographics, IBD attributes, and treatment methods were investigated as the factors with potential impacts on vaccination outcomes.One hundred twenty-five patients with IBD were evaluated. The number of patients with Anti-HBs >10  IU/L was 71 (56.8%), and the number of patients with anti-HBs >100  IU/L was 50 (40%). Age, disease activity, Crohn disease subtype, and immunosuppressive treatment (IST) were found to have significant effects on immune response (P = 0.011, P < 0.001, P = 0.003, and P < 0.001, respectively). With multivariate analysis, age < 45 years (OR 3.1, 95% CI 1.2-8.3, P = 0.020), vaccination during remission (OR 5.6, 95% CI 2.3-14, P < 0.001), and non-IST (OR 11.1, 95% CI 2.9-43.2, P = 0.001) had favorable effects on the occurrence of adequate vaccine response.The likelihood of achieving adequate immune response with standard HBV vaccination protocol in IBD is low. Selecting vaccination protocols with more potent immunogenicity is a better approach to achieve effective vaccine response in patients with multiple unfavorable factors.

2014 KLCSG-NCC Korea Practice Guideline for the Management of Hepatocellular Carcinoma

The guideline for the management of hepatocellular carcinoma (HCC) was first developed in 2003 and revised in 2009 by the Korean Liver Cancer Study Group and the National Cancer Center, Korea. Since then, many studies on HCC have been carried out in Korea and other countries. In particular, a substantial body of knowledge has been accumulated on diagnosis, staging, and treatment specific to Asian characteristics, especially Koreans, prompting the proposal of new strategies. Accordingly, the new guideline presented herein was developed on the basis of recent evidence and expert opinions. The primary targets of this guideline are patients with suspicious or newly diagnosed HCC. This guideline provides recommendations for the initial treatment of patients with newly diagnosed HCC.

Whole Tumor Antigen Vaccines: Where Are We?

With its vast amount of uncharacterized and characterized T cell epitopes available for activating CD4⁺ T helper and CD8⁺ cytotoxic lymphocytes simultaneously, whole tumor antigen represents an attractive alternative source of antigens as compared to tumor-derived peptides and full-length recombinant tumor proteins for dendritic cell (DC)-based immunotherapy. Unlike defined tumor-derived peptides and proteins, whole tumor lysate therapy is applicable to all patients regardless of their HLA type. DCs are essentially the master regulators of immune response, and are the most potent antigen-presenting cell population for priming and activating naïve T cells to target tumors. Because of these unique properties, numerous DC-based immunotherapies have been initiated in the clinics. In this review, we describe the different types of whole tumor antigens that we could use to pulse DCs ex vivo and in vivo. We also discuss the different routes of delivering whole tumor antigens to DCs in vivo and activating them with toll-like receptor agonists.

Prevention of perinatal hepatitis B transmission in Haimen City, China: Results of a community public health initiative

In regions where hepatitis B virus (HBV) is endemic, perinatal transmission is common. Infected newborns have a 90% chance of developing chronic HBV infection, and 1 in 4 will die prematurely from HBV-related liver disease. In 2010, the Hepatitis B Foundation and the Haimen City CDC launched the Gateway to Care campaign in Haimen City, China to improve awareness, prevention, and control of HBV infection citywide. The campaign included efforts to prevent perinatal HBV transmission by screening all pregnant women for hepatitis B surface antigen (HBsAg), following those who tested positive, and administering immunoprophylaxis to their newborns at birth. Of 5407 pregnant women screened, 185 were confirmed HBsAg-positive and followed until delivery. At age one, 175 babies were available for follow up testing. Of those, 137 tested negative for HBsAg and positive for antibodies to HBsAg, indicating protection. An additional 34 HBsAg-negative babies also tested negative for antibodies to HBsAg or had indeterminate test results, were considered to have had inadequate immune responses to the vaccine, and were given a booster dose. A higher prevalence of nonresponse to HBV vaccine was observed among babies born to hepatitis B e antigen (HBeAg)-positive mothers and mothers with high HBV DNA titers. The remaining 4 babies tested positive for HBsAg and negative for antibodies, indicative of active HBV infection. The mothers of all 4 had viral loads ≥8×10(6) copies/ml in the third trimester. Although inadequate response or nonresponse to HBV vaccine was more common among babies born to HBeAg-positive and/or high viral load mothers, these risk factors did not completely predict nonresponsiveness. All babies born to HBV-infected mothers should be tested upon completion of the vaccine series to ascertain adequate protection. Some babies of HBeAg-positive mothers with high viral load may still become HBV infected despite timely immunoprophylaxis with HBV vaccine and HBIG.

Chimeric hepatitis B virus (HBV)/hepatitis C virus (HCV) subviral envelope particles induce efficient anti-HCV antibody production in animals pre-immunized with HBV vaccine

The development of an effective, affordable prophylactic vaccine against hepatitis C virus (HCV) remains a medical priority. The recently described chimeric HBV-HCV subviral envelope particles could potentially be used for this purpose, as they could be produced by industrial procedures adapted from those established for the hepatitis B virus (HBV) vaccine. We show here, in an animal model, that pre-existing immunity acquired through HBV vaccination does not influence the immunogenicity of the HCV E2 protein presented by these chimeric particles. Thus, these chimeric HBV-HCV subviral envelope particles could potentially be used as a booster in individuals previously vaccinated against HBV, to induce protective immunity to HCV.

Persistence of immunity in healthy adults aged ≥ 50 years primed with a hepatitis B vaccine 3 years previously

Hepatitis B vaccines do not generate protective immune responses in older adults as effectively as they do in children and young adults. Improved formulations of existing vaccines may have the potential to improve this. This study investigated the persistence of serum antibodies against hepatitis B surface antigens (anti-HBs) 3.1-3.5 years following primary vaccination with 3 doses of HBvaxPRO® or Engerix B™ in healthy adults aged ≥ 50 years who were further challenged with 1 dose of recombinant hepatitis B antigen. This was an open-label extension study. Individuals (N = 204) with a mean (standard deviation) age at enrollment of 63.7 (7.0) years receiving HBvaxPRO® or Engerix B™ in a randomized, double-blind primary study were challenged with 1 dose of HBvaxPRO® (10 μg). Anti-HBs were measured pre- and 30 days post-challenge. 45.5% (34.8, 56.4 [95% CI]) of individuals who received HBvaxPRO® in the per protocol set (PPS) had anti-HBs titers ≥ 10 mIU/mL pre-challenge and 85.2% (76.1, 91.9) 1-month post-challenge. In those who received Engerix B™ in the primary vaccination series, the results were 58.8% (48.6, 68.5) and 88.3% (80.5, 93.8), respectively. The challenge dose of HBvaxPRO® was generally well tolerated. Subjects aged ≥ 50 years receiving a challenge dose of HBvaxPRO® demonstrated immune memory against hepatitis B 3 years after a 3-dose primary. The safety profile of this challenge dose of HBvaxPRO® was consistent with the well-established safety profile of the vaccine HBvaxPRO®.

Impact of surveillance of hepatitis b and hepatitis c in patients with inflammatory bowel disease under anti-TNF therapies: multicenter prospective observational study (REPENTINA 3)

AIMS

Assess IBD patients starting anti-TNF for the impact of preventive measures in HBV and/or HCV, and the predictive response factors to HBV vaccination.

METHODS

Multicenter prospective study including 389 IBD patients. Four interventions were established: I-1) anti-HBs <100IU/L: HBV vaccination with double doses at 0-1-2months, and revaccination if titres <100IU/L (seroprotection defined as anti-HBs10-100IU/L and effective vaccination anti-HBs >100IU/L); I-2) anti-HBs >100IU/L (previous effective vaccination): monitoring levels; I-3) anti-HBc and/or HCV+: analysis every two months; I-4) HBsAg+: start anti-virals.

RESULTS

I-1 and I-2) For first vaccination, effective vaccination and seroprotection were obtained in 26.4% and 43.5%, and for revaccination 31.3% and 44.4%, respectively. Predictive factors of effective vaccination were age ≤30years (OR=2.2) and being vaccinated simultaneously with anti-TNF (OR=5.2) instead of late vaccination, whereas age ≤30years (OR=2.6) and anti-TNF monotherapy (OR=2.4) were predictive for seroprotection. 80.8% of patients previously vaccinated maintained titres at 29months follow-up. The only factor related to maintaining titres was previous vaccination versus achieving effective vaccination during anti-TNF (HR=2.49); I-3 and I-4) HBV-DNA + without reactivation was detected in 7% of 29 anti-HBc. No reactivation was found in the remaining HCV (n=5) or HBsAg (n=4) patients.

CONCLUSIONS

1) Response to vaccination/revaccination is low in patients with anti-TNF. Young patients vaccinated at the beginning of anti-TNF and receiving it as a monotheraphy showed better response. 2) Long-lasting effective vaccination is greatest in patients previously vaccinated. 3) Following-up the established surveillance and/or preventive anti-viral therapy seems to be safe in HBV and HCV patients.

Getting the shots: methods to gain adherence to a multi-dose vaccination program for inner city, drug-involved prostitution communities

Street-based sex-work and poly-substance drug use, coupled with low vaccination rates and limited utilization of the mainstream health care system, put the sex worker communities of Bogotá's city center at extreme risk of infection with the hepatitis B virus (HBV). Vaccination is critical to maintaining low prevalence of the disease and low incidence of new cases, yet the floating and inconsistent nature of Bogotá's drug-involved female and transsexual prostitution communities make it difficult to complete a 3-dose vaccination program. Between December 2011 and March of 2012, the Fénix Foundation collaborated with the Bogotá Health Department to deliver free HBV vaccines to this vulnerable population. This paper outlines methods used in the vaccination program to generate a 37.7% adherence rate, significantly higher than that previously reported for HBV vaccination programs also targeting marginalized populations. This program's practices are based on the Fénix peer leader method, and are offered as a model that can be applied to other health interventions operating in analogous contexts, with similarly high-risk populations.

Long-term T-cell-mediated immunologic memory to hepatitis B vaccine in young adults following neonatal vaccination

BACKGROUND

The long-term duration of cell-mediated immunity induced by neonatal hepatitis B virus (HBV) vaccination is unknown.

OBJECTIVES

Study was designed to determine the cellular immunity memory status among young adults twenty years after infantile HB immunization.

PATIENTS AND METHODS

Study subjects were party selected from a recent seroepidemiologic study in young adults, who had been vaccinated against HBV twenty years earlier. Just before and ten to 14 days after one dose of HBV vaccine booster injection, blood samples were obtained and sera concentration of cytokines (interleukin 2 and interferon) was measured. More than twofold increase after boosting was considered positive immune response. With regard to the serum level of antibody against HBV surface antigen (HBsAb) before boosting, the subjects were divided into four groups as follow: GI, HBsAb titer < 2; GII, titer 2 to 9.9; GIII, titer 10 to 99; and GIV, titers ≥ 100 IU/L. Mean concentration level (MCL) of each cytokines for each group at preboosting and postboosting and the proportion of responders in each groups were determined. Paired descriptive statistical analysis method (t test) was used to compare the MCL of each cytokines in each and between groups and the frequency of responders in each group.

RESULTS

Before boosting, among 176 boosted individuals, 75 (42.6%) had HBsAb 10 IU/L and were considered seroprotected. Among 101 serosusceptible persons, more than 80% of boosted individuals showed more than twofold increase in cytokines concentration, which meant positive HBsAg-specific cell-mediated immunity. MCL of both cytokines after boosting in GIV were decreased more than twofold, possibly because of recent natural boosting.

CONCLUSIONS

Findings showed that neonatal HBV immunization was efficacious in inducing long-term immunity and cell-mediated immune memory for up to two decades, and booster vaccination are not required. Further monitoring of vaccinated subjects for HBV infections are recommended.

Response to booster doses of hepatitis B vaccine among young adults who had received neonatal vaccination

Background

Newborns who have received hepatitis B immunization in 1980s are now young adults joining healthcare disciplines. The need for booster, pre- and post-booster checks becomes a practical question.

Aims

The aim of this study is to refine the HBV vaccination policy for newly admitted students in the future.

Methods

A prospective study on medical and nursing school entrants to evaluate hepatitis B serostatus and the response to booster doses among young adults.

Findings

Among 212 students, 17–23-year-old, born after adoption of neonatal immunization, 2 (0.9%) were HBsAg positive, 40 (18.9%) were anti-HBs positive. At 1 month after a single-dose booster for anti-HBs-negative students, 14.5% had anti-HBs <10 mIU/mL, 29.0% and 56.5% were 10–100 and >100 mIU/mL, respectively. The anti-HBs levels were significantly higher for females than males (mean [SD]: 431 [418] vs. 246 [339] mIU/mL, P = 0.047). At 2–4 month after the third booster dose, 97.1% had anti-HBs >100 mIU/mL and 2.9% had 10–100 mIU/mL.

Conclusions

Pre-booster check is still worthwhile to identify carriers among newly recruited healthcare workers born after adoption of neonatal immunization. A 3-dose booster, rather than a single dose, is required for the majority to achieve an anti-HBs level >100 mIU/mL, as memory immunity has declined in a substantial proportion of individuals. Cost-effectiveness of post-booster check for anti-HBs is low and should be further evaluated based on contextual specific utilization of results.

Prevalence of HBV and HCV among outpatients in the Plovdiv region of Bulgaria, 2010-2011

Viral hepatitis, particularly hepatitis B and C, are diseases with worldwide distribution that present a significant public health problem. Seroprevalence studies allow assessment of the extent of the disease burden, the identification of populations at risk and the monitoring trends over time. A multi-center seroprevalence study, carried out in Bulgaria (covering the five largest cities - Sofia, Plovdiv, Varna, Pleven, and Stara Zagora) in 1999-2000 estimated a crude seroprevalence rate of 3.9% for HBsAg and 1.3% for anti-HCV. A decade later, comparable rates were observed in a study including 865 outpatients consulting a clinical laboratory in Plovdiv, the second largest administrative region in Bulgaria. The crude seroprevalence rate measured for hepatitis B (HBsAg) was 3.9%. The HBsAg prevalence rate in individuals ≤19 years of age (targeted by vaccination) was significantly lower compared to the rate in adults ≥20 years of age -1% versus 4.8%. The lack of dynamics in the overall level of HBsAg carriers is likely related to the excessively low hepatitis B vaccine coverage in individuals, born before the introduction of the universal vaccination of newborns in August 1991. Anti-HCV antibodies were detected in 0.7% of the subjects.

Preventing infective complications in inflammatory bowel disease

Over the past decade there has been a dramatic change in the treatment of patients with Crohn’s disease and ulcerative colitis, which comprise the inflammatory bowel diseases (IBD). This is due to the increasing use of immunosuppressives and in particular the biological agents, which are being used earlier in the course of disease, and for longer durations, as these therapies result in better clinical outcomes for patients. This, however, has the potential to increase the risk of opportunistic and serious infections in these patients, most of which are preventable. Much like the risk for potential malignancy resulting from the use of these therapies long-term, a balance needs to be struck between medication use to control the disease with minimization of the risk of an opportunistic infection. This outcome is achieved by the physician’s tailored use of justified therapies, and the patients’ education and actions to minimize infection risk. The purpose of this review is to explore the evidence and guidelines available to all physicians managing patients with IBD using immunomodulating agents and to aid in the prevention of opportunistic infections.

Key outcomes and addressing remaining challenges--perspectives from a final evaluation of the China GAVI project

During the China GAVI project, implemented between 2002 and 2010, more than 25 million children received hepatitis B vaccine with the support of project, and the vaccine proved to be safe and effective. With careful consideration for project savings, China and GAVI continually adjusted the budget, additionally allowing the project to spend operational funds to support demonstration projects to improve timely birth dose (TBD), conduct training of EPI staff, and to monitor the project impact. Results from the final evaluation indicated the achievement of key outcomes. As a result of government co-investment, human resources at county level engaged in hepatitis B vaccination increased from 29 per county on average in 2002 to 66 in 2009. All project counties funded by the GAVI project use auto-disable syringes for hepatitis B vaccination and other vaccines. Surveyed hepatitis B vaccine coverage increased from 71% in 2002 to 93% in 2009 among infants. The HBsAg prevalence declined from 9.67% in 1992 to 0.96% in 2006 among children under 5 years of age. However, several important issues remain: (1) China still accounts for the largest annual number of perinatal HBV infections (estimated 84,121) in the WHO WPR region; (2) China still lacks a clear national policy for safe injection of vaccines; (3) vaccination of high risk adults and protection of health care workers are still not implemented; (4) hepatitis B surveillance needs to be refined to more accurately monitor acute hepatitis B; and (5) a program for treatment of persons with chronic HBV infection is needed. Recommendations for future hepatitis B control include: using the lessons learned from the China GAVI project for future introductions of new vaccines; addressing unmet needs with a second generation hepatitis B program to reach every infant, including screening mothers, and providing HBIG for infants born to HBsAg positive mothers; expanding vaccination to high risk adults; addressing remaining unsafe injection issues; and improving monitoring of acute hepatitis B. This paper describes findings and discusses perspectives from a final project evaluation, a national stratified validated cross-sectional survey done in October 2010.

Impact of free on-site vaccine and/or healthcare workers training on hepatitis B vaccination acceptability in high-risk subjects: a pre-post cluster randomized study

Despite recommendations for adults at high-risk of hepatitis B virus (HBV) infection, HBV vaccine uptake remains low in this population. A pre-post randomized cluster study was conducted to evaluate the impact of on-site free HBV vaccine availability and/or healthcare worker training on HBV vaccination acceptability in high-risk adults consulting in 12 free and anonymous HIV and hepatitis B/C testing centres (FATC). The FATC were randomly allocated into three groups receiving a different intervention: training on HBV epidemiology, risk factors and vaccination (Group A), free vaccination in the FATC (Group B), both interventions (Group C). The main outcomes were the increase in HBV vaccination acceptability (receipt of at least one dose of vaccine) and vaccine coverage (receipt of at least two doses of vaccine) after intervention. Respectively, 872 and 809 HBV-seronegative adults at high-risk for HBV infection were included in the pre- and post-intervention assessments. HBV vaccination acceptability increased from 14.0% to 75.6% (p <0.001) in Group B and from 17.1% to 85.8% (p <0.001) in Group C and HBV vaccine coverage increased from 9.4% to 48.8% (p <0.001) in Group B and from 11.2% to 41.0% (p <0.001) in Group C. The association of training and free on-site vaccine availability was more effective than free on-site vaccine availability alone to increase vaccination acceptability (ratio 1.14; from 1.02 to 1.26; p 0.017). No effect of training alone was observed. These results support the policy of making HBV vaccine available in health structures attended by high-risk individuals. Updating healthcare workers' knowledge on HBV virus and its prevention brings an additional benefit to vaccination acceptability.

Prevalence of chronic hepatitis B virus infection before and after implementation of a hepatitis B vaccination program among children in Nepal

BACKGROUND

In Nepal, an estimated 2-4% of the population has chronic hepatitis B virus (HBV) infection. To combat this problem, from 2002 to 2004, a national three dose hepatitis B vaccination program was implemented to decrease infection rates among children. The program does not currently include a birth dose to prevent perinatal HBV transmission. In 2012, to assess the impact of the program, we conducted a serosurvey among children born before and after vaccine introduction.

METHODS

In 2012, a cross-sectional nationally representative stratified cluster survey was conducted to estimate hepatitis B surface antigen (HBsAg) prevalence among children born from 2006 to 2007 (post-vaccine cohort) and among children born from 2000 to 2002 (pre-vaccine cohort). Demographic data, as well as written and oral vaccination history were collected. All children were tested for HBsAg; mothers of HBsAg positive children were also tested. Furthermore, we evaluated the field sensitivity and specificity of the SD Bioline HBsAg rapid diagnostic test by comparing results with an enzyme immunoassay.

RESULTS

Among 2181 post-vaccination cohort children with vaccination data by either card or recall, 86% (95% confidence interval [CI] 77-95%) received ≥ 3 hepatitis B vaccine doses. Of 1200 children born in the pre-vaccination cohort, 0.28% (95% CI 0.09-0.85%) were positive for HBsAg; of 2187 children born in the post-vaccination cohort, 0.13% (95% CI 0.04-0.39%) were positive for HBsAg (p=0.39). Of the six children who tested positive for HBsAg, two had mothers who were positive for HBsAg. Finally, we found the SD Bioline HBsAg rapid diagnostic test to have a sensitivity of 100% and a specificity of 100%.

CONCLUSIONS

This is the first nationally representative hepatitis B serosurvey conducted in Nepal. Overall, a low burden of chronic HBV infection was found in children born in both the pre and post-vaccination cohorts. Current vaccination strategies should be continued.

Alternative dosage schedules with HPV virus-like particle vaccines

HPV vaccines can prevent multiple cancers in women and men. Difficulties in the cost and completion of the three-dose vaccine series have led to considerations of alternative dose schedules. In clinical trials, three doses given within a 12-month period versus the standard 6-month period yielded comparable results, and immunogenicity appears comparable with two doses in adolescent females compared to the three-dose series in adult females. While the data are generally supportive of moving to a two-dose vaccine schedule among young female adolescents, the adoption of a two-dose vaccine schedule still poses a potential risk to the strength and longevity of the immune response. Public health authorities implementing a two-dose vaccine schedule should devise risk management strategies to minimize the potential impact on cancer prevention.

Risk factors associated with immunoprophylaxis failure against mother to child transmission of hepatitis B virus and hepatitis B vaccination status in Yunnan province, China

OBJECTIVE

To explore the risk factors associated with immunoprophylaxis failure against mother to child transmission of hepatitis B virus (HBV) and hepatitis B vaccination status in Yunnan province, China.

METHODS

Multicenter cluster sampling was used to select pregnant women who were positive for hepatitis B surface antigen (HBsAg). HBV immunoprophylaxis was carried out for the newborns. Blood samples were collected and tested for HBV markers from 7 to 10 month old infants. The factors were analyzed by univariate and logistic regression.

RESULTS

A total of 2765 mothers and their infants were enrolled. The failure rate of prevention of mother to child transmission (PMTCT) was 4.12%. The rate of timely HepB1 vaccination within 24h was 98.04%, the rate of three-dose vaccination was 92.30% and the rate of hepatitis B immune globulin (HBIG) administration was 68.97%. Place of residence, maternal education, gestational age and birth weight were related to administration of HBV immunoprophylaxis. It was remarkable that the rate of HBIG administration of infants was only 63.89% with whose mothers were both HBsAg and hepatitis B e antigen (HBeAg)-positive. Further analysis showed that there were three risk factors associated with HBV immunoprophylaxis failure: mothers who were positive for HBsAg and HBeAg, maternal HBVDNA level, and HBIG administration or not.

CONCLUSIONS

PMTCT of HBV was well implemented in Yunnan. However, in order to achieve optimal prevention of vertical HBV transmission, it is mandatory to make additional efforts to improve the implementation of regulatory HBV immunoprophylaxis, especially for HBsAg-positive pregnant women.

Hepatitis B virus infection among HIV-infected pregnant women in Malawi and transmission to infants

BACKGROUND & AIMS

The extent of HBV infection to infants of HBV/HIV-coinfected pregnant women in sub-Saharan Africa is unknown. The aim of this study was to assess prevalence of HBV infection among antiretroviral-naïve, HIV-infected pregnant women in Malawi and examine HBV transmission to their infants.

METHODS

Plasma from 2048 HIV-infected, Malawian women and their infants were tested for markers of HBV infection. Study participants were provided standard-of-care health services, which included administration of pentavalent vaccine to infants at 6, 10, and 14 weeks of age.

RESULTS

One-hundred and three women (5%) were HBsAg-positive; 70 of these HBsAg-positive women were also HBV-DNA-positive. Sixteen women (0.8%) were HBV-DNA-positive but HBsAg-negative. Five of 51 infants (9.8%) born to HBsAg-positive and/or HBV-DNA-positive women were HBV-DNA-positive by 48 weeks of age.HBV DNA concentrations of two infants of mothers who received extended lamivudine-containing anti-HIV prophylaxis were <4 log10 IU/ml compared to ⩾ 8 log10 IU/ml in three infants of mothers who did not.

CONCLUSIONS

HBV DNA was detected in nearly 10% of infants born to HBV/HIV-coinfected women. Antenatal testing for HIV and HBV, if instituted, can facilitate implementation of prophylactic measures against infant infection by both viruses.

Cost-effectiveness analysis of a hepatitis B vaccination catch-up program among children in Shandong Province, China

OBJECTIVE

The aim of the study was to estimate long-term cost‑effectiveness of a hepatitis B vaccination catch-up program among children born between 1994 and 2001 (when they were 8‑15 y old) in Shandong province, China, to provide information for nationwide evaluation and future policy making.

METHODS

We determined the cost-effectiveness of the catch-up program compared with the status quo (no catch-up program). We combined a Decision Tree model and a Markov model to simulate vaccination and clinical progression after hepatitis B virus (HBV) infection. Parameters in the models were from the literature, a field survey, program files, and the National Notifiable Disease Reporting System (NNDRS). The incremental cost‑effectiveness ratio (ICER) was used to compare the 2 alternative strategies. One-way sensitivity analysis, 2-way sensitivity analysis, and probability sensitivity analysis were used to assess parameter uncertainties.

RESULTS

The catch-up program was dominant compared with the status quo. Using a total of 5.53 million doses of vaccines, the catch-up program could prevent 21,865 cases of symptomatic acute hepatitis B, 3,088 carrier states with positive hepatitis B surface antigen (HBsAg), and 812 deaths due to HBV infection. The catch-up program could add 28,888 quality-adjusted life years (QALYs) and save $192.01 million in the targeted population in the future. The models were robust, considering parameter uncertainties.

CONCLUSION

The catch-up program in Shandong province among children born between 1994 and 2001 was 'very cost-saving.' It could save life years and reduce total future costs. Our study supported the desirability and impact of such a catch-up program throughout China.

Association of early age at establishment of chronic hepatitis B infection with persistent viral replication, liver cirrhosis and hepatocellular carcinoma: a systematic review

Age at infection with hepatitis B virus (HBV) is a known risk factor for chronic HBV infection. However, in addition, there is some evidence that early age at infection further increases the risk of primary liver cancer beyond its association with increased risk of chronic infection. This systematic review of observational studies assesses the association between age at initiation of chronic HBV infection and liver cirrhosis, hepatocellular carcinoma, and their predictors including indicators of ongoing viral replication and hepatic damage. The review includes birth order and maternal HBV serology as proxies for age at infection. Electronic searches in two English-language (Medline and Embase, until Jan 2012) and two Chinese-language (CNKI and SinoMed, until Sep 2012) databases without language restriction and manual search through reference lists identified 7,077 papers, of which 19 studies of 21 outcomes (8 primary liver cancer, 1 liver cirrhosis, 10 viral replication and 2 liver inflammation) are included. One study directly examined the age at infection in a longitudinal cohort, 12 assessed maternal sero-status and 6 investigated birth order. The direction of associations in all studies was in accordance with our hypothesis that earlier age at infection is associated with worse outcomes in addition to its effect of increasing the probability of chronic HBV infection. This has implications for the control of hepatitis B.

Thermodynamic origins of protein folding, allostery, and capsid formation in the human hepatitis B virus core protein

HBc, the capsid-forming "core protein" of human hepatitis B virus (HBV), is a multidomain, α-helical homodimer that aggressively forms human HBV capsids. Structural plasticity has been proposed to be important to the myriad functions HBc mediates during viral replication. Here, we report detailed thermodynamic analyses of the folding of the dimeric HBc protomer under conditions that prevented capsid formation. Central to our success was the use of ion mobility spectrometry-mass spectrometry and microscale thermophoresis, which allowed folding mechanisms to be characterized using just micrograms of protein. HBc folds in a three-state transition with a stable, dimeric, α-helical intermediate. Extensive protein engineering showed thermodynamic linkage between different structural domains. Unusual effects associated with mutating some residues suggest structural strain, arising from frustrated contacts, is present in the native dimer. We found evidence of structural gatekeepers that, when mutated, alleviated native strain and prevented (or significantly attenuated) capsid formation by tuning the population of alternative native conformations. This strain is likely an evolved feature that helps HBc access the different structures associated with its diverse essential functions. The subtle balance between native and strained contacts may provide the means to tune conformational properties of HBc by molecular interactions or mutations, thereby conferring allosteric regulation of structure and function. The ability to trap HBc conformers thermodynamically by mutation, and thereby ablate HBV capsid formation, provides proof of principle for designing antivirals that elicit similar effects.

Post-vaccination serological test results of infants at risk of perinatal transmission of hepatitis B using an intensified follow-up programme in a London centre

Immunisation of infants born to hepatitis B virus (HBV) infected mothers is an important public health measure to prevent mother-to-child transmission of HBV. Post-vaccination serological tests (PVST) inform the success of the infant HBV immunisation programme and identify infected infants. Previous studies suggested that the rates of PVST in the UK programme were unsatisfactory. We introduced an intensified local follow-up programme and offered an earlier PVST 2-3 months after the third vaccination at age 4-5 months. Of 219 infants born between 2009 and 2011, 193 infants (88.1%) had at least one PVST: 145 (66.2%) early; 94 (42.9%) standard; 46 (21.0%) both and 26 (11.9%) never tested. Twenty-four infants were identified as high risk for mother-to-child transmission according to national criteria and received both hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine at birth. These infants had a significantly lower hepatitis B surface antibody (anti-HBs) levels at early PVST compared to the lower risk group who received hepatitis B vaccine only (median of 59 vs. 376 mIU/ml, P=0.006). None of the infants tested were infected with hepatitis B. This study illustrates that the rate of PVST can be improved by using an intensified follow-up programme offering an early PVST. The significantly lower anti-HBs levels in the HBIG subgroup is of concern as this group of infants is already at higher risk for acquiring HBV infection. Infants with poor antibody responses can be identified by an early PVST and offered a timely extra booster dose.

Vaccination strategies in patients with IBD

Patients with IBD are at increased risk of infection, in part owing to the disease itself, but mostly because of treatment with immunosuppressive drugs. Although many of these infections are vaccine-preventable, vaccination coverage in patients with IBD is extremely low. The vaccine strategies examined in this Review are based on data that enable us to provide practical advice for clinicians. Clinical evidence indicates that vaccines do not increase the risk of relapse in patients with IBD. Live vaccines are contraindicated in immunocompromised individuals, but inactivated vaccines can be safely administered. Most patients receiving immunosuppressive therapy develop an immune response after vaccination, but response rates might differ from those of nonimmunosuppressed individuals. Therefore, vaccination status should be checked and updated upon diagnosis of IBD.

Efficacy of the vaccination in inflammatory bowel disease

Inflammatory bowel disease (IBD) is associated with conditions that may predispose to infections, such as the lack of an appropriate innate immune response to infectious agents, malnutrition, surgery, and immunosuppressive and biological drugs. Some of these infections may be preventable by vaccination. Therefore, for this particular patient population, the benefits of implementing a well-established immunization protocol in daily clinical practice are potentially even greater than for the general population. In recent years international consensus guidelines have been published, but in spite of theses recommendations, studies have shown that a significant number of patients with IBD remain inadequately immunized. Another important issue regarding immunization in this population is that vaccine efficacy among patients receiving immunosuppressive therapies has been variable. In a healthy population, a humoral immune response to hepatitis B vaccination (HBV) is expected in > 90%, whereas a much lower rate is achieved in the IBD patients. Immunosuppressive, anti-tumor necrosis factor therapy and disease activity have been implicated in the impaired efficacy of the vaccination. The serological response to HBV should be confirmed and patients with an inadequate response should receive a second full series of vaccine. Modified dosing regimens, including doubling the standard antigen dose, might increase the effectiveness. Response to influenza, pneumococcal and tetanus immunization is still not clear, as there are studies that show a normal response to the vaccination while others demonstrate a lack of efficacy. We pose a series of questions on the efficacy of the different vaccinations recommended for IBD patients and attempt to answer them using scientific evidence.

Hepatitis B vaccine in celiac disease: Yesterday, today and tomorrow

Some studies showed that in celiac patients the immunological response to vaccination is similar to that one found in general population except for vaccine against hepatitis B virus (HBV). The non-responsiveness to HBV vaccine has also been described in healthy people, nevertheless the number of non-responders has been demonstrated to be higher in celiac disease (CD) patients than in healthy controls. Several hypothesis explaining this higher rate of unresponsiveness to HBV vaccine in CD patients have been described, such as the genetic hypothesis, according with CD patients carrying the disease-specific haplotype HLA-B8, DR3, and DQ2, show a lower response to HBV vaccine both in clinical expressed CD patients and in healthy people carrying the same haplotype. On the other hand, it has been demonstrated that the gluten intake during the vaccination seems to influence the response to the same vaccine. Moreover, it has been demonstrated a possible genetic predisposition to hepatitis B vaccine non-responsiveness likely due to the presence of specific human leukocyte antigen haplotypes and specific single nucleotide polymorphism in genes of cytokine/cytokine receptors and toll like receptors, but the pathogenic mechanism responsible for this low responsiveness still remains unclear. The aim of this review is to focus on the possible pathogenic causes of unresponsiveness to HBV vaccine in CD patients and to propose an alternative vaccination schedule in order to improve the responsiveness to HBV vaccine in this at-risk patients.

Comparison of the effectiveness of two protocols for vaccination (standard and double dosage) against hepatitis B virus in patients with inflammatory bowel disease

BACKGROUND

The response rate to hepatitis B virus (HBV) vaccination in patients with inflammatory bowel disease (IBD) is low.

AIM

To compare two vaccination protocols-the standard dose and the double dose-in IBD patients.

METHODS

Patients diagnosed with IBD from three tertiary hospitals were vaccinated against HBV with two different protocols: the standard protocol (Engerix-B single dose at 0, 1 and 6 months) and the new faster protocol based on a double dose (Engerix B double dose at 0, 1 and 2 months). Anti-HBs titres were measured 1-3 months after the last dose. A multivariate analysis was performed to identify factors that were predictive of response to the vaccine.

RESULTS

The study sample comprised 148 patients (mean age 40 years, 69% Crohn's disease), 70% of whom were receiving immunosuppressive therapy (22% thiopurines, 23% anti-TNF and 25% both). The standard protocol was followed in 46% of patients and the double dose protocol in 54%. Considering anti-HBs >10 IU/L as a successful response to vaccination, the seroconversion rate was higher among patients vaccinated with the double dose than with the standard dose: 75% (95% CI, 65-85%) vs. 41% (95% CI, 29-54%) (P < 0.001). In the multivariate analysis, vaccination with the double dose was the only factor associated with a better response to the vaccine (OR, 4; 95% CI, 2-8; P < 0.001).

CONCLUSIONS

The response rate to the HBV vaccination in IBD patients is low. Administration of a double dose was associated with a higher response rate. Therefore, the double dose protocol could be a suitable option in patients with IBD.

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.

Virologic factors associated with failure to passive-active immunoprophylaxis in infants born to HBsAg-positive mothers

In infants born to hepatitis B surface antigen (HBsAg)-positive mothers, failure after passive-active immunization still occurs. The role of maternal hepatitis B DNA level and other risk factors in this setting remains unclear. This study retrospectively evaluated virologic and other risk factors associated with immunoprophylaxis failure in infants born to HBsAg-positive mothers. Between January 2007 and March 2010, we reviewed the clinical and virologic tests in 869 mother-infant pairs. All infants received the identical passive-active immunization schedule after birth. The failure infants (HBsAg positive at 7-12 months of age) were compared to infants who were HBsAg negative when tested during this time period. Among 869 infants, 27 (3.1%) infants were immunoprophylaxis failures and the other 842 (96.9%) infants remained HBsAg negative. When mothers' pre-delivery HBV DNA levels were stratified to <6, 6-6.99, 7-7.99 and ≥ 8 log(10) copies/mL, the corresponding rates of immunoprophylaxis failure were 0%, 3.2% (3/95), 6.7% (19/282) and 7.6% (5/66), respectively (P < 0.001 for the trend). All failure infants were born to hepatitis B e antigen (HBeAg)-positive mothers. Multivariate logistic regression analysis identified maternal HBV DNA levels [odds ratio (OR) = 1.88, 95% confidence interval (CI): 1.07-3.30] and detectable HBV DNA in the cord blood (OR = 39.67, 95% CI: 14.22-110.64) as independent risk factors for immunoprophylaxis failure. All failure infants were born to HBeAg-positive mothers with HBV DNA levels ≥ 6 log(10) copies/mL. The presence of HBV DNA in cord blood predicted failure to passive-active immunization.

Protective effect of hepatitis B vaccine combined with two-dose hepatitis B immunoglobulin on infants born to HBsAg-positive mothers

BACKGROUND

Despite the use of hepatitis B (HB) vaccine and hepatitis B immunoglobulin (HBIG), a portion of infants are still non- or low-responders, or even immunoprophylaxis failure. We aimed to determine the immune response in the infants from the mothers being positive for hepatitis B surface antigen (HBsAg), by which the infants received three doses of HB vaccine in combination with two-dose 200 IU HBIG injections.

METHODS

In this retrospective study, 621 infants from HBsAg-positive mothers in Beijing YouAn Hospital between January 2008 and December 2009 were included. All the infants were given three doses of 10 µg HB vaccine (at 0, 1 and 6 months of age) and two-dose of 200 IU HBIG (at birth and in 2 weeks of age). Serum HBsAg and antibody to HBsAg (anti-HBs) in all the infants were determined at 7 months of age.

RESULTS

Of the 621 infants, 2.9% were immunoprophylaxis failure (positive for HBsAg), 1.4% were non-responders (anti-HBs undetectable), 95.7% were responders. The 594 responders could be categorized into three subsets, 22 were 10 to 99 IU/L for anti-HBs levels, 191 were 100 to 999 IU/L, and 381 were ≥1000 IU/L. The immunoprophylaxis failure rate was at 0% and 5.2% for the infants of HBeAg-negative and HBeAg-positive mothers(P<0.001). Infants from mothers with detectable HBV DNA had higher incidence of immunoprophylaxis failure than those of mothers without detectable HBV DNA (P = 0.002). The factors including gender, birth weight, gestation weeks, the rates of maternal HBeAg-positive, and detectable HBV DNA did not contribute to the no response to HB vaccination.

CONCLUSIONS

Through vaccination by three doses of HB and two-dose of HBIG, majority of the infants (95.7%) achieved a protective level of anti-HBs at 7 months of age. Maternal HBeAg-positive and HBV DNA detectable were associated with the immunoprophylaxis failure, but not contribute to the non- or low-response to HB vaccination.

Impaired humoral response to vaccines among HIV-exposed uninfected infants

Little is known about the vaccine protective response for infants born from HIV-infected mothers. We evaluated the antibody response to hepatitis B, tetanus, and diphtheria vaccine in vertically HIV-exposed uninfected infants and compared them to those of control infants not exposed to the virus. The quantitative determination of specific neutralizing antibodies against hepatitis B, diphtheria, and tetanus were performed blindly on serum samples. The results showed that 6.7% of the HIV-exposed uninfected individuals were nonresponders to hepatitis B vaccine (anti-HBs titer, <10 mIU/ml), and 64.4% were very good responders (anti-HBs titer, ≥1,000 mIU/ml), whereas only 3.6% of the nonexposed infants were nonresponders (χ(2)=10.93; 1 df). The HIV-exposed uninfected infants showed protective titers for diphtheria and tetanus but lower geometric mean anti-tetanus titers compared to those of the HIV-unexposed infants. Our data point to the necessity of evaluating vaccine immune responses in these children and reinforced that alterations in lymphocyte numbers and functions reported for newborns from HIV-infected mothers interfere with the vaccine response.

Partial virological response to entecavir in treatment-naive patients with chronic hepatitis B

BACKGROUND

The proposed definition of a partial virological response (PVR) to nucleos(t)ide analogue therapy in the 2009 European Association for the Study of the Liver (EASL) guidelines is based on limited evidence, especially in terms of the cutoff HBV DNA level and the time point at which to judge it. This study assessed optimal PVR criteria for predicting virological response (VR) at week 96 in treatment-naive patients with chronic hepatitis B (CHB) receiving entecavir (ETV).

METHODS

A total of 175 patients (126 men, 49 women) who completed 96 weeks of first-line ETV therapy were prospectively recruited. For predicting VR at week 96, the area under the receiver operating characteristic curve (AUC) was used to find the optimal time point and the Youden index was used to calculate the optimal cutoff HBV DNA level.

RESULTS

After 96 weeks of ETV therapy, 139 (79.4%) patients achieved VR. The AUC at week 48 was significantly better than that at week 24 for predicting VR at week 96 (P=0.023). The optimal cutoff HBV DNA level at week 48 was 35 IU/ml. Forty-one (23.4%) patients met this PVR criteria of ETV (HBV DNA level >35 IU/ml at week 48).

CONCLUSIONS

An HBV DNA level >35 IU/ml at week 48 is the optimal PVR criteria for predicting non-VR at week 96 in treatment-naive patients with CHB who are receiving ETV. This study supports the proposed EASL PVR for ETV based on scientific evidence.

Changes in human Langerhans cells following intradermal injection of influenza virus-like particle vaccines

There is a significant gap in our fundamental understanding of early morphological and migratory changes in human Langerhans cells (LCs) in response to vaccine stimulation. As the vast majority of LCs studies are conducted in small animal models, substantial interspecies variation in skin architecture and immunity must be considered when extrapolating the results to humans. This study aims to determine whether excised human skin, maintained viable in organ culture, provides a useful human model for measuring and understanding early immune response to intradermally delivered vaccine candidates. Excised human breast skin was maintained viable in air-liquid-interface organ culture. This model was used for the first time to show morphological changes in human LCs stimulated with influenza virus-like particle (VLP) vaccines delivered via intradermal injection. Immunohistochemistry of epidermal sheets and skin sections showed that LCs in VLP treated skin lost their typical dendritic morphology. The cells were more dispersed throughout the epidermis, often in close proximity to the basement membrane, and appeared vertically elongated. Our data provides for increased understanding of the complex morphological, spatial and temporal changes that occur to permit LC migration through the densely packed keratinocytes of the epidermis following exposure to vaccine. Significantly, the data not only supports previous animal data but also provides new and essential evidence of host response to this vaccination strategy in the real human skin environment.