Acute hepatitis B 14 years after the implementation of universal vaccination in Italy: areas of improvement and emerging challenges

The First 30 Years of the Universal Hepatitis-B Vaccination-Program in Italy: A Health Strategy with a Relevant and Favorable Economic-Profile

In 1991, Italy was one of the first countries worldwide to introduce a universal hepatitis-B vaccination for children. Since then, epidemiological data have clearly demonstrated the huge clinical benefits of the vaccination. The aim of this study was to update the favorable economic impact of the hepatitis B virus (HBV) vaccination, 30 years after its implementation. A mathematical model was developed to simulate the clinical/economic impact of the universal HBV-vaccination program versus a hypothetical no-vaccination scenario as a posteriori analysis. We assessed the vaccination benefits over a 30-year-immunization-period (1991−2020), and the following period, 2021−2070. Our data showed a big drop in HBV-related diseases (−82% in infections, chronic disease, and hepatocellular-carcinoma cases), and related costs (−67% in the immunization period and −85% in 2021−2070), attributable to vaccination. The return on investment (ROI) and the benefit-to-cost (BCR) ratios are >1 for the first thirty-year-immunization-period, and are predicted to almost triplicate the economic savings in the period 2021−2070, both for the National Health Service (NHS) and from societal perspectives. Our model confirmed that the implementation of universal HBV-vaccination in Italy during the first 30 years continues to be a cost-saving strategy, and more advantageous effects will be further achieved in the future. The HBV-vaccination strategy greatly expresses a huge impact in both the short- and long-term, and from the clinical and economic point-of-views.

Prevalence of hepatitis B surface antigen (HBsAg) in blood donor population in Bosnia and Herzegovina: impact of the pre-donation questionnaire implementation and mandatory hepatitis B virus (HBV) vaccination schedule - 20 years' experience of the University Clinical Hospital Mostar

OBJECTIVES

Currently, there are limited data on the prevalence of HBsAg in Bosnia and Herzegovina. This study aimed to evaluate the trend of HBsAg prevalence during a period of 20 years in relation to the implementation of pre-donation questionnaires based on parenteral and sexual risk factors and mandatory HBV vaccination.

MATERIAL AND METHODS

This is a retrospective analysis performed on 67,336 blood donors at the University Clinical Hospital Mostar during three distinct periods: before introducing of mandatory HBV vaccination and pre-donation blood donor questionnaires (1998-2002); after introducing of pre-donation blood donor questionnaires, but without mandatory immunized blood donors (2004-2008); and after introducing of mandatory pre-donation blood donor questionnaires and mandatory vaccination (2015-2019).

RESULTS

According to implementation of mandatory pre-donation blood donor questionnaires and mandatory HBV vaccination the prevalence of HBsAg significantly decreased among blood donors in all three studied period of time (0.303% in 1998-2002, 0.236% in 2004-2008, and 0.021% in 2015-2019; P < 0.001). Out of 67,336 tested donors, there were 98 (0.145 %) HBsAg-positive donors during analysed periods, with a mean age of 34.76±11.37 years. The mean age of HBsAg-positive donors was 30.72±10.40, 37.56±10.13, and 47.28±12.14) in the 1998-2002, 2004-2008, and 2015-2019 periods, respectively (P < 0.001).

CONCLUSION

This study clearly shows a decreased rate of HBV infections among blood donors with respect to implementation of the HBV vaccination schedule and mandatory pre-donation blood donor questionnaires based on parenteral and sexual risk factors.

Effectiveness of Hepatitis B Vaccination Campaign in Italy: Towards the Control of HBV Infection for the First Time in a European Country

Background: In 1991, a mass immunization campaign against the hepatitis B virus (HBV) for children and teenagers was introduced in Italy. This study evaluated the impact of the immunization campaign on the incidence and modes of HBV transmission. Method: Acute HBV cases of viral hepatitis were reported to the National Surveillance System (SEIEVA). Hepatitis A cases reported to the same system were used as controls to calculate the adjusted odds ratios and the population attributable risk for potential risk factors. Results: The incidence of acute HBV declined from 5.0 in 1990 to 0.4 in 2019 per 100,000 population. The fall was almost total in people targeted by the campaign: in 2019, zero cases (100% reduction) in the age-group 0–14 years and 0.1 cases per 100,000 population (99.4% reduction) in the age-group 15–24 years were reported. In the decade 2010–2019, nearly one-fifth (19.3%) of cases occurred in foreigners. Intravenous drug use is no longer a risk factor (OR = 0.7; 95% CI = 0.5–1.02). Beauty treatments, risky sexual exposure, and household contact with an HBsAg carrier were found to be independent predictors of acute hepatitis B. Conclusions: The HB vaccination campaign proved effective in minimising acute HBV in Italy. Control of the infection is close to being reached for the first time in Europe.

The effectiveness of the national hepatitis B vaccination program 25 years after its introduction in Iran: a historical cohort study

Introduction

Hepatitis B virus (HBV) is responsible for one of the most common human viral infections. An estimated 257 million people are living with chronic HBV infection worldwide, and mortality has reached 900,000 deaths in recent years. In 2001, the World Health Organization reported a prevalence of chronic hepatitis B infection in Iran between 2–7%.

Objective

To assess the effect of the national HBV mass vaccination program after 25 years.

Methods

A retrospective cohort study was conducted in vaccinated and unvaccinated people according to the year of birth. Blood samples were obtained from each enrolled person and data about demographic variables, and medical and vaccination history were collected using a standardized questionnaire. Persons were considered uninfected if they were negative for both HBsAg and anti-HBc. Also, Vaccine effectiveness was measured by calculating the risk of disease among vaccinated and unvaccinated persons and defining the percentage risk reduction of infection in the vaccinated group.

Results

A total of 2720 persons were interviewed. The rate of HBV breakthrough infection among the vaccinated group was significantly lower than in unvaccinated group. One hundred ninety-four cases with positive HBV markers of infection were identified. The risk ratio of HBV infection was 0.71, 95% CI: 0.54–0.94 (vaccinated/unvaccinated). The estimated vaccination effectiveness against Hepatitis B infection was 29% (95% CI: 6%–46%).

Conclusions

Iran has successfully combined hepatitis B vaccination into regular immunization programs. The WHO goal of reducing HBsAg prevalence to an equivalent of 1% by 2020 has been reached. With respect to vaccination effectiveness and low prevalence of the disease in the country, catch-up hepatitis B vaccination programs for adolescents can guarantee the immunity of the population.

Effectiveness and impact of the hepatitis B vaccination program in preadolescents in Catalonia 21 years after its introduction

Hepatitis B is a viral disease of global importance. In Catalonia in the 1980s, the seroepidemiological pattern of HBV infection was low-intermediate. In 1990, the Expert Committee on Vaccinations of the Department of Health of the Generalitat of Catalonia evaluated the systematic introduction of hepatitis B vaccination in preadolescents, maintaining the vaccination of risk groups. The objective of this study was to estimate the effectiveness and impact of the systematic hepatitis B vaccination programme in preadolescents in Catalonia 21 years after its introduction. A retrospective cohort study was conducted, comparing the disease incidence in vaccinated and unvaccinated cohorts. Cases of hepatitis B were defined as those reported by the General Subdirectorate of Surveillance and Response to Public Health Emergencies between 2000 and 2014. The incidence rate was 2.5 per 100,000 persons in 1991 and 1.2 per 100,000 persons in 2014, a reduction of 52%. During the study period, 388 cases of hepatitis B infection were notified, of which three were classified as vaccine failures. Vaccine effectiveness was 99.30% (95% CI: 97.83-99.78) and the population prevented fraction in the cohorts of preadolescents studied was 64.56% (95% CI: 60.45-68.66). The effectiveness and impact of the hepatitis B vaccination program in preadolescents in Catalonia is high, with the consequent benefits for the population.

HBV seroprevalence after 25 years of universal mass vaccination and management of non-responders to the anti-Hepatitis B vaccine: An Italian study among medical students

According to international guidelines, healthcare workers and medical students immunized against HBV are periodically tested for anti-HBs IgG. Subjects who show an anti-HBs titre <10 mUI/mL must receive additional vaccine doses to induce a measurable antibody response. This study aimed to evaluate the long-time immunogenicity of anti-hepatitis B vaccination in a sample of medical students and residents of the University of Bari who attended the Hygiene Department for biological risk assessment (April 2014-June 2017). The strategy for the management of nonresponder subjects was evaluated. A total of 3676 students and residents were invited for testing according to a standardized protocol. Anti-HBs IgG was tested for in 3140 (85.4%) subjects: 1174/3140 (37.7%) subjects were negative. 14.6% (128/808) of subjects who received the vaccine during their 12th year of life and 45.8% (1056/2305) of subjects immunized during the first year of life (P < 0.0001) were negative. 1005/1174 (85.6%) seronegative subjects received a booster dose, and 903/1005 (89.9%) were tested for anti-HBs 1 month after the booster dose: 82/903 (9.1%) subjects were still negative. Of these, 56/82 (68.3%) received 2 additional doses of vaccine and 52/56 (92.9%) were tested 1 month after the third dose: 50/52 subjects (96.2%) developed a positive titre. In conclusion, several medical students, immunized at birth or at young age against HBV, did not develop protective titres against the virus. Our management strategy (booster retest; for negative subjects, 2 doses and retest) seems consistent with the purpose of evidencing immunological memory.

What is changed in HBV molecular epidemiology in Italy?

Hepatitis B virus (HBV) infection represents the most common cause of chronic liver diseases worldwide. Consequently, to the introduction of the universal HBV vaccination program, the prevalence of hepatitis B surface antigen was markedly reduced and less than 1% of the population of Western Europe and North America is chronically infected. To date, despite great advances in therapeutics, HBV chronic infection is considered an incurable disease. Ten hepatitis B virus genotypes (A-J) and several subgenotypes have been identified so far, based on intergroup divergences of 8% and 4%, respectively, in the complete viral genome. HBV-D genotype has been found throughout the world, with highest prevalence in the Mediterranean area. In the present review, several articles concerning HBV epidemiology, and phylogeny in Italy have been analyzed, mainly focusing on the changes occurred in the last decade.

Detection of hepatitis B virus DNA and HBsAg from postmortem blood and bloodstains

A large number of accidental virus infections occur in medical and non-medical workers exposed to infectious individuals and materials. We evaluated whether postmortem blood and bloodstains containing hepatitis B virus (HBV) are infectious. HBV-infected blood and bloodstains were stored for up to 60 days at room temperature and subsequently screened for hepatitis B surface antigen (HBsAg) and HBV DNA. In addition, HBV-positive postmortem blood was added to a cell line and the production of HBV virions was examined over a period of 7 days. HBsAg and HBV DNA were detected in all samples stored for 60 days at room temperature. HBV-positive postmortem blood successfully infected the cell line and progeny viruses were produced for up to 6 days. Thus, it is crucial that due care is taken when handling not only living material infected with HBV, as well as other harmful viruses, but also blood or body fluids from cadavers or medical waste.

Response to anti-HBV vaccine and 10-year follow-up of antibody levels in healthcare workers

BACKGROUND

Despite improvements in public health and antiviral treatments, vaccination is still the most effective means of prevention of hepatitis B virus (HBV) infection. However, little is known about the duration of protection given by the anti-HBV vaccine. Healthcare workers represent a category at risk not only of contracting infection but also of being a source of contagion to patients.

OBJECTIVES

To assess individual responses to the anti-HBV vaccine and duration of protection 10 years after its administration in a cohort of healthcare workers employed by the University Hospital 'G. Martino' in Messina, Italy.

METHODS

One hundred and seventy medical staff who had been vaccinated following an incident carrying risk of HBV infection were included in this study. The group was followed over a 10-year period, and HBV antibody levels were assessed using an automated microparticle enzyme immunoassay.

RESULTS

Protective antibody levels (≥10 mIU/ml) were found in 65% of subjects who had completed the full vaccine schedule (three doses) and in 35% of subjects who had only received one or two doses of anti-HBV vaccine. Moreover, 10 years after vaccination, HBV antibody levels were inversely related to age at vaccination (P < 0.001). No differences were found between males and females.

CONCLUSIONS

This study, in line with the literature, shows the importance of completing the full vaccine schedule (three doses). Moreover, in order to have an effective and durable antibody response and avoid the risk of contracting HBV after an injury at work, it is important to recommend anti-HBV vaccination at a young age, ideally during childhood in accordance with the national vaccination policy.

Epidemiological and clinical scenario of chronic liver diseases in Italy: Data from a multicenter nationwide survey

BACKGROUND

The last Italian prevalence survey on chronic liver diseases (CLD) was performed in 2001. The present study evaluated the changes occurring over thirteen years.

METHODS

We enrolled 2,557 CLD consecutive patients in 16 Italian liver units in 2014.

RESULTS

HBV etiology accounted for 513 (20.2%) cases, alone in 439 and associated with HCV and/or alcohol abuse in 74. Of these 513, 11.9% were anti-HDV-positive and 7.2% HBeAg-positive. HCV alone was responsible for 50.3% of CLD and with alcohol abuse for 5.9%. HCV RNA was detected in 64.0% of the anti-HCV-positive patients tested. HCV genotyping, performed for 899 patients, showed genotype-1a, 1b, 2, 3, 4 and 5 respectively in 16.5%, 45.5%, 15.4%, 8.2%, 15.1% and 0.2%. Alcohol abuse alone was responsible for 6.4% of cases and NAFLD/NASH for 6.3%. Liver cirrhosis (p<0.001) and HCC (p<0.001) were more frequent in alcoholic than viral etiologies. HCV and alcohol etiologies were more frequent in 2001 than 2014 (from 69.9% to 59.9% and from 23.0% to 12.3%, respectively). HBV showed a similar impact. In all etiologies, the 2001 CLD cases were 10 years younger and with a significantly lower rate of cirrhosis than the 2014 cases.

CONCLUSION

The changes in HCV, HBV and alcohol etiologies may help apply more appropriate healthcare strategies.

Impact and long-term protection of hepatitis B vaccination: 17 years after universal hepatitis B vaccination in Tunisia

Hepatitis B virus (HBV) vaccination has been part of the Expanded Programme of Immunization (EPI) in Tunisia since 1995. The aim of this study was to evaluate, for the first time, the impact of mass vaccination in Tunisia 17 years after this programme was implemented, and in parallel, assess the long-term persistence of anti-HBs antibody in the vaccinated Tunisian population. A total of 1422 students were recruited (703 vaccinated, 719 non-vaccinated). HBV seromarkers were checked. None of the students from either group had positive HBsAg. The overall prevalence of anti-HBc was 0·8%. A Significantly higher prevalence of anti-HBc was noted in unvaccinated students than in vaccinated (1·4% vs. 0·3%, P = 0·02). The overall seroprotection rate (anti-HBs titre ⩾10 mIU/ml) was 68·9% in vaccinated subjects. Seroprotection rates and geometric mean titres decreased significantly with increasing age, reflecting waning anti-HBs titre over time. No significant difference was detected between seroprotection rates and gender or students' area of origin. Incomplete vaccination was the only factor associated with an anti-HBs titre <10 mIU/ml. This study demonstrates the excellent efficacy of the HBV vaccination programme in Tunisia 17 years after its launch. However, a significant decline of anti-HBs seroprotection has been observed in ⩾15-year-old adolescents which places them at risk of infection. Additional studies are needed in hyperendemic regions in Tunisia.

Age-dependent decrease of anti-HBs titers and effect of booster doses using 2 different vaccines in Palestinian children vaccinated in early childhood

Immunization against hepatitis B virus (HBV) has proven to be highly effective and led to significant reduction of new infections worldwide. However, protective immunity measured by anti-HBs titers may decrease to critical levels in the years after basal immunization, particularly in case of exposure to HBV variants different from the vaccine strain. We tested 400 Palestinian children between one and 19 years of age for their anti-HBs titer, challenged the immune memory of those with low or absent anti-HBs with 2 types of hepatitis B vaccines and determined thereafter the anti-HBs titer. At the age of one, 92.2% of the children presented with protective anti-HBs titers (≥ 10 mIU/ml) with the majority having ≥ 100 mIU/ml. Protective immunity was still high at ages 2 (87.5%) and 4 (95%), declining by age 5 and 6 (from 69.2% to 66.7%) and down to an average of 39.8% between the ages of 7 and 19. 160 children with a nonprotective or low immune response challenged with either the yeast-derived Engerix-B or the mammalian cell-derived preS1-containing Sci-B-Vac vaccine showed an anamnestic immune response. 92.4% and 85.9% of the children challenged with one dose Sci-B-Vac and Engerix-B presented with anti-HBs titers >100 mIU/ml respectively. Our results reveal that vaccine-induced protective anti-HBs titers against HBV decrease rapidly beyond the age of 6 in Palestinian children, but can be strongly enhanced with a single booster vaccine dose, independent of brand and antigen composition. Our data suggest that a booster vaccine dose against HBV during school years may be useful.

Prevention of hepatitis B virus-associated liver diseases by antiviral therapy

Hepatitis B virus (HBV) is a major cause of acute and chronic hepatitis, cirrhosis and hepatocellular carcinoma, particularly in Asia-Pacific countries. The major complications in HBV carriers are hepatocellular carcinoma (HCC), liver failure and esophageal varices following the progression to cirrhosis, while some develop HCC without cirrhosis. The progression to liver fibrosis and these other complications could be prevented by treatment with nucleos(t)ide analogues (NUCs); however, NUCs must be continuously administered for a long time. Peginterferon could lead to HBV surface antigen loss. It is difficult to use peginterferon in HBV-infected patients with decompensated cirrhosis. Acute liver failure due to HBV infection and acute exacerbation of chronic hepatitis B could be treated by NUCs. Universal vaccination programs against HBV could prevent new HBV infections globally. Here, we review the currently available treatments for HBV infection.

Acute Hepatitis B After the Implementation of Universal Vaccination in Italy: Results From 22 Years of Surveillance (1993-2014)

BACKGROUND

Hepatitis B vaccination has proven to be very safe and highly effective. This study assessed the proportion of successfully vaccinated individuals among cases with acute hepatitis B, the proportion of preventable cases if individuals were vaccinated as recommended, and the reasons for failures.

METHODS

We analyzed data reported to the Italian Surveillance System for Acute Viral Hepatitis from 1993 to 2014.

RESULTS

A total of 362 of 11 311 (3.2%) cases with acute hepatitis B were vaccinated. Of the 277 cases for whom immunization data were available, 50 (18%) received a complete vaccination course according to the correct schedule and before exposure to hepatitis B virus. Molecular characterization of 17 of these cases showed that 6 were infected with S-gene mutants. Among the 10 949 unvaccinated cases, 213 (1.9%) escaped mandatory vaccination and 2821 (25.8%) were not vaccinated despite being at increased risk of infection. Among the latter, the most common risk factors were cohabitation with hepatitis B surface antigen (HBsAg) carriers, intravenous drug use, and homosexual/bisexual practices. Thirty-seven percent of the unvaccinated households with HBsAg carriers were aware of their risk. Lack of trust in the vaccination, negative attitude, and inaccurate beliefs followed by lack of or poor communication and low perceived severity of the disease were the most frequent reasons for vaccine hesitancy.

CONCLUSIONS

Development of acute disease in successfully vaccinated individuals is a rare event. Further efforts are needed to enhance the vaccine coverage rate in individuals at increased risk of infection.

The epidemiological changes of HCV and HBV infections in the era of new antiviral therapies and the anti-HBV vaccine

The World Health Organization (WHO) resolution adopted in 2010 recognized viral hepatitis as a global health problem. In April 2014, for the first time, the WHO produced guidelines for the screening, care and treatment of persons with hepatitis C infections. In May 2014, a follow-up resolution urged WHO Member States to develop and implement a national strategy for the prevention, diagnosis and treatment of viral hepatitis based on the local epidemiological context. Although blood donor screening, which began in the early 1990s, has reduced the spread of the virus in the population, the WHO estimates that 150 million people are chronically infected with hepatitis C virus (HCV) and are at an increased risk of developing liver cirrhosis and hepatocellular carcinoma. In addition, 3-4 million people are infected each year. HCV treatment is currently evolving rapidly, and several drugs are in various stages of development. With regard to the hepatitis B virus (HBV), in March 2015, the WHO published the first guidelines for the prevention, care and treatment of persons with chronic hepatitis B infection, which were designed to complement the recent guidelines on HCV. Although the introduction of an effective vaccine against the hepatitis B virus has reduced the prevalence and health and economic impact of hepatitis in industrialized countries, the WHO estimates that more than 2 billion people are HBV-infected and 350 million people are chronic carriers.

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.

Strategies to control hepatitis B: Public policy, epidemiology, vaccine and drugs

The last 50 years of hepatitis B research has resulted in the development of effective screening assays for surveillance, vaccines for prevention and antiviral drugs that significantly improve patient clinical outcomes. Not surprisingly then, the global epidemiology of hepatitis B virus (HBV) is set to change dramatically over the next decade. For example, the success and the high coverage of universal HBV vaccination and the ageing cohorts of patients with chronic hepatitis B (CHB) will result in reductions of incidence and prevalence of chronic hepatitis, cirrhosis and probably hepatocellular carcinoma. This will be further accelerated by the impressive progress in the treatment outcomes for patients with CHB. In spite of this success, challenges remain, such as planning for the impact of migration from countries with high prevalence rates to those countries with low rates of HBV infection. The recent establishment of the World Health Organisation Global Hepatitis Program with the provision of a framework for global action has become the cornerstone for all countries to now frame their own particular national responses to control hepatitis B. An effective policy framework can prevent new infections, ensure people can access clinical care, and in doing so reduce the burden of infection at an individual, country and regional level. These developments present a real opportunity to reduce the significant, social and economic burden of global hepatitis B, ultimately the critical next steps to render the world hepatitis B free.

Hepatitis B virus genotype distribution and genotype-specific BCP/preCore substitutions in acute and chronic infections in Argentina

AIM

In order to assess Hepatitis B Virus genotype (g) and subgenotype (sg) implications in the course of infection, 234 HBsAg positive patients in different infection stages were characterized (66 acute infections, 63 HBeAg positive chronic infections and 105 anti-HBe positive chronic infections).

RESULTS

Overall, sgA2 (17.9%), gD (20.9%), sgF1b (34.2%) and sgF4 (19.7%) were the most prevalent. Subgenotype F1b was overrepresented in acute and chronic HBeAg infections (56.1%), whereas gD was the most frequent (40.0%) in anti-HBe positive chronic infections. Among chronic infections, HBeAg positivity rates were 50.0, 12.5, 62.8 and 35.3% for sgA2, gD, sgF1b and sgF4, respectively (p <0.05). A bias toward BCP/preCore mutations was observed among genotypes. In anti-HBe positive chronic infections, sgF1b was more prone to have A1762T/G1764A mutation than sgA2, sgF4 and gD (75.0, 40.0, 33.3 and 31.8%, p<0.005), whereas in the pC region, gD and sgF4 were more likely to have G1896A than sgA2 and sgF1b (81.0, 72.7, 0.0 and 31.3%, p <0.001). The unexpected low frequency of the G1896A mutation in the sgF1b (despite carrying 1858T) prompted us to perform a further analysis in order to identify genotype-specific features that could justify the pattern mutations observed. A region encompassing nucleotides 1720 to 1920 showed the higher dissimilarity between sgF1b and sgF4. Genotypes and subgenotypes carrying the 1727G, 1740C and 1773T polymorphisms were prevented to mutate position 1896.

DISCUSSION

HBeAg seroconversion is a critical event in the natural history of HBV infection. Differences in the HBeAg positivity rate might be relevant since different studies have observed that delayed HBeAg seroconversion is associated with a more severe clinical course of infection, highlighting the critical role that genotypes/subgenotypes might play in the progression of HBV infection. Polymorphisms in the regions 1720 to 1920 could be involved in the molecular mechanisms underlying seroconversion of each genotype/subgenotype.

Prophylactic vaccination against hepatitis B: achievements, challenges and perspectives

Large-scale vaccination against hepatitis B virus (HBV) infection started in 1984 with first-generation vaccines made from plasma of chronic carriers containing HBV surface antigen (HBsAg). Thereafter, it was replaced in most countries by second-generation vaccines manufactured in yeast cells transformed with gene S encoding HBsAg. Both generations of vaccines have been applied for universal neonate and early childhood vaccination worldwide and have led to a 70-90 % decrease in chronic HBV carrier rates. However, 10-30% of newborns from HBsAg/HBeAg-positive mothers cannot be protected by passive/active vaccination alone and become chronic HBV carriers themselves. Asymptomatic occult HBV infections are frequent even in those who have protective levels of anti-HBs. Suboptimal protection may be due to heterologous HBsAg subtypes that are present in 99% of HBV carriers worldwide. Second-generation vaccines contain partially misfolded HBsAg and lack preS1 antigen that carries the major HBV attachment site and neutralizing epitopes. Third-generation vaccines produced in mammalian cells contain correctly folded HBsAg and neutralizing epitopes of the preS antigens, induce more rapid protection, overcome nonresponse to second-generation vaccines and, most importantly, may provide better protection for newborns of HBV-positive mothers. PreS/S vaccines expressed in mammalian cells are more expensive to manufacture, but introduction of more potent HBV vaccines should be considered in regions with a high rate of vertical transmission pending assessment of health economics and healthcare priorities. With optimal vaccines and vaccination coverage, eradication of HBV would be possible.

Clinical and virological characteristics associated with severe acute hepatitis B

To identify early predictors of a severe or fulminant course in patients with acute viral hepatitis B (AVH-B). One hundred and thirty-eight patients with symptomatic acute hepatitis B observed from 1999 to 2012 were enrolled. For each patient, the demographics, risk factors for the acquisition of hepatitis B virus (HBV) infection, clinical, biochemical and virological data (HBV DNA, HBV DNA sequences) were recorded and analysed. The HBV mutants in the polymerase region were sought in 110 (87%) patients by direct sequencing, and the rtM204V/I mutations also by an allele-specific PCR. AVH-B was severe in 13 (9.4%) of the 138 patients enrolled, fulminant in 6 (4.3%) and with a normal clinical course in 119. The 19 patients with severe or fulminant AVH-B more frequently than the 119 with a normal course stated intravenous drug use (63.2% versus 36.1%, p 0.04) and were HBV-DNA negative (31.6% versus 11.8%, p 0.03) and anti-hepatitis C virus (HCV) positive (57.9% versus 19.3%, p 0.0008); the prevalences of different HBV genotypes and of the rtM204V/I mutant were similar in these three forms of AVH-B. A multivariate logistic regression analysis identified a pre-existing HCV chronic infection as the only factor independently associated with a severe or fulminant clinical course of AVH-B (OR 4.89, 95% CI 1.5-15.94, p 0.01). A pre-existing HCV chronic infection was identified as the only factor independently associated with a severe clinical presentation of acute hepatitis B, an association most probably due to the combination of the liver lesions caused by acute hepatitis B and the pre-existing histological abnormalities related to HCV chronic infection.

Hepatitis B virus: Where do we stand and what is the next step for eradication?

Hepatitis B (HB) virus (HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, is endemic worldwide. Hepatitis B vaccines became commercially available in the 1980s. The World Health Organization recommended the integration of the HB vaccine into the national immunisation programs in all countries. HBV prevention strategies are classified into three groups: (1) universal vaccination alone; (2) universal vaccination with screening of pregnant women plus HB immune globulin (HBIG) at birth; and (3) selective vaccination with screening of pregnant women plus HBIG at birth. Most low-income countries have adopted universal vaccine programs without screening of pregnant women. However, HB vaccines are not widely used in low-income countries. The Global Alliance for Vaccine and Immunization was launched in 2000, and by 2012, the global coverage of a three-dose HB vaccine had increased to 79%. The next challenges are to further increase the coverage rate, close the gap between recommendations and routine practices, approach high-risk individuals, screen and treat chronically infected individuals, and prevent breakthrough infections. To eradicate HBV infections, strenuous efforts are required to overcome socioeconomic barriers to the HB vaccine; this task is expected to take several decades to complete.

Molecular epidemiology of hepatitis B virus genotypes circulating in acute hepatitis B patients in the Campania region

Fifty-three HBV-DNA-positive patients with symptomatic acute hepatitis B were enrolled from 1999 to 2010 to evaluate molecular and phylogenetic changes in HBV in southern Italy. HBV polymerase region was evaluated by direct sequencing in plasma samples obtained at first observation. Different data sets were aligned and a phylogenetic tree was inferred using PhyML program. Statistical robustness was confirmed with a bootstrap analysis. A Bayesian Markov chain Monte Carlo method and a Bayesian skyline plot were used to estimate the evolution of our samples. The dN/dS rate (ω) was estimated by the maximum likelihood approach to investigate the presence of codons under positive selection. The MacClade program was used to test viral gene out/in flow only among HBV-D3 subgenotype patients with different risk factors. Of the 53 patients, 83% were born in Italy and 17% were foreigners. HBV genotype D was prevalent (64.1%), followed by genotype A (26.4%), E (3.8%), and F (5.7%). The prevalent subgenotype was D3 (70.6%). The Bayesian tree of the 24 D3 subgenotypes showed two main clades both dated 1994; 40% of viral gene flow observed was from intravenous drugs users and heterosexual patients. Phylogenetic analysis of HBV isolates showed that HBV-D3 remains the prevalent genotype, but also subgenotype A2 has become frequent in southern Italy. This may be of clinical relevance in years to come, since patients with HBV-genotype-A chronic infection less frequently than those with genotype D develop HBeAg-negative chronic hepatitis and respond more frequently to alfa-interferon treatment.

Epidemiology of acute and chronic hepatitis B and delta over the last 5 decades in Italy

The spread of hepatitis B virus (HBV) infection has gradually decreased in Italy in the last 5 decades as shown by the steady reduction in the incidence rates of acute hepatitis B, from 10/100000 inhabitants in 1984 to 0.85/100000 in 2012, and by the reduced prevalence of hepatitis B surface antigen (HBsAg)-positive cases among chronic hepatitis patients with different etiologies, from 60% in 1975 to about 10% in 2001. The prevalence of HBsAg chronic carriers in the general population also decreased from nearly 3% in the 1980s to 1% in 2010. Linked to HBV by its characteristics of defective virus, the hepatitis delta virus (HDV) has shown a similar epidemiological impact on the Italian population over time. The incidence of acute HDV infection decreased from 3.2/100000 inhabitants in 1987 to 0.8/100000 in 2010 and the prevalence of HDV infection in HBsAg chronic carriers decreased from 24% in 1990 to 8.5% in 2006. Before the beneficial effects of HBV mass vaccination introduced in 1991, the decreased endemicity of HBV and HDV infection in Italy paralleled the improvement in screening blood donations, the higher standard of living and impressive reduction in the birth rate associated with a marked reduction in the family size. A further contribution to the decline in HBV and HDV infections most probably came from the media campaigns to prevent the spread of human immunodeficiency virus infection by focusing the attention of the general population on the same routes of transmission of viral infections such as unsafe sexual intercourse and parenteral exposures of different kinds.

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.

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.

Trends of hepatitis B notification rates in Turkey, 1990 to 2012

Turkey is a country with intermediate endemicity for hepatitis B, and approximately 4% of the population are HBsAg-positive. A number of measures have been implemented to prevent hepatitis B infection. In 1998, hepatitis B antigen was included in the national immunisation programme, and infants have since been vaccinated with three doses. Catch-up strategies, vaccination for high risk groups and screening measures were also adopted. The aim of this study was to evaluate the impact of the prevention and control strategies on hepatitis B notification rates in Turkey in the period from 1990 to 2012, using data from the national surveillance system. Secular trends revealed that rates showed an initial increasing trend, followed by a steady decline from 2005. The most dramatic decline occurred among children younger than 15 years, highlighting the benefits of vaccination and catch-up strategies. However, vaccination cannot fully explain the decrease in this age group. Socioeconomic development, through interrupting the horizontal transmission may also have contributed. After 2005, a steady decline was achieved also among those 15 years and older. The rates in adults were higher, which indicates that stronger prevention measures are needed to target this group, particularly men.

Universal hepatitis B vaccination in Belgium: impact on serological markers 3 and 7 years after implementation

Hepatitis B virus (HBV) can be eliminated by effective universal vaccination. In Belgium, a free-of-charge HBV vaccination programme in infants with catch-up in adolescents was introduced in 1999. To evaluate the effects in <20-year-olds, seroprotection (anti-HBs >11 mIU/ml, according to the assay) and markers of infection (anti-HBc, HBsAg) were assessed in 2443 residual sera collected 7–8 years after implementation of the programme. The maximal prevalence of a solely anti-HBs seroprotective (‘vaccinated’) serostatus was 82·9% at age 1 year and 60·5% at age 13 years. A clear increase was found in age cohorts targeted by the campaign after a similar serosurvey conducted 4 years earlier. The prevalence of HBV infection remained unchanged at a low level (1·8% in 2006) similar to pre-vaccination data (1993–1994). We conclude that universal HBV vaccination has achieved overall high levels of vaccine-induced immunity, despite regional variations, which may give rise to pockets of susceptible young adults in the future.

Hepatitis B screening: who to target? A French sexually transmitted infection clinic experience

BACKGROUND & AIMS

Hepatitis B virus (HBV) infection is a major public health burden in France and worldwide. Routine screening for hepatitis B is not currently recommended in France. Medical experts and public health agencies opinions can differ concerning targeting criteria. Our study aims at developing a risk assessment strategy for identifying possible hepatitis B cases among the patients consulting in a French Sexually Transmitted Infection (STI) clinic.

METHODS

6194 asymptomatic patients requesting an STI screening were also screened for hepatitis B infection. The association between hepatitis B surface antigen (HBsAg) positivity and/or total hepatitis B core antibody (anti-HBc) positivity and self-reported risk factors for hepatitis were analysed.

RESULTS

Only male gender, lack of employment, and birth, in medium or high endemic country, were independently associated with HBsAg positivity in multivariate analysis. Sexual behaviour or self-reported vaccination status is therefore not necessary to target high-risk populations. These three simple criteria could save 25% of unnecessary tests and 6-16% undiagnosed hepatitis B compared to usual targeting criteria.

CONCLUSIONS

To detect HBsAg carriers, only three simple targeting criteria, without taking into account the self-reported vaccination status or sexual behaviour, could improve screening efficiency and save unnecessary testing.

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.

Sero-epidemiology of hepatitis B markers in the population of Tuscany, Central Italy, 20 years after the implementation of universal vaccination

Italy was one of the first industrialized countries to introduce a program of universal vaccination against hepatitis B in 1991. Twenty years later we verified the impact of universal immunisation on the epidemiology of hepatitis B infection by analyzing the prevalence of specific viral markers (anti-HBs, anti-HBc and HBsAg). The ELISA tests were performed on residual blood samples collected by 0.05% of the resident population aged 1-50 years in Tuscany (Italy). About 63% of subjects aged < 30 years were anti-HBs positive compared to about 25% in older subjects, without differences between genders. About 22% of subjects over 40 years were anti-HBc-positive compared to 5% in the younger age groups. The number of HBsAg-positive subjects was almost 10 fold higher in the unvaccinated age groups than in the cohorts involved in the universal vaccination program. The results of our study show the persisting high anti-HBs reactivity in vaccinated cohorts, while HBV markers related to natural exposure or persistent infection remain remarkably higher in older age groups. This sero-epidemiological study supports with prevalence data the downward incidence trend of acute hepatitis B highlighted by epidemiological surveillance systems, and corroborates the forecast for elimination of hepatitis B in Italy in a few decades.

The impact of a vaccination campaign against hepatitis B on the further decrease of hepatitis B virus infection in a southern Italian town over 14 years

BACKGROUND

Hepatitis B virus infection has decreased in Italy. The aims of this study were to identify changes, if any, in the epidemiological pattern of HBV infection in a southern Italian town first surveyed in 1996 and to assess the effectiveness of vaccination campaign against hepatitis B.

METHODS

In 2010, subjects were selected from the census by a systematic 1:4 random sampling procedure. Hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B core antigen (anti-HBc) were detected by ELISA. Associations (odds ratios) linking exposure to hepatitis B virus infection to potential risk factors were estimated by univariate and multivariate analyses.

RESULTS

Of the 1100 eligible subjects, 1020 (92.0%) agreed to participate. The prevalences of HBsAg (0.6%) and anti-HBc (15.2%) were significantly lower than in 1996 (0.8% and 21.5%) (p<0.01). No subject below 30 years of age (those that had been targeted for compulsory immunization) had been exposed to HBV infection. At multiple logistic regression analysis, age>45 years (OR=9.8; 95% CI=5.1-18.7) and past use of glass syringes (OR=1.9; 95% CI=1.2-3.1) independently predicted the likelihood of anti-HBc positivity.

CONCLUSIONS

These results, albeit obtained in a small town and thus not generalizable, confirm the continuous decreasing trend of HBV infection and demonstrate the effectiveness of the Italian hepatitis B vaccination program.

Serological pattern of Hepatitis B, C, and HIV infections among immigrants in Sicily: epidemiological aspects and implication on public health

The objective of this study was to describe the prevalence of Hepatitis B virus (HBV), Hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infections in a cohort of immigrants living in Palermo, Sicily. The study was carried out in the period May 2006-June 2010 and recruited a total of 393 patients (59.8% males-median age of 32.6 years). All patients were tested for serological markers of HBV, HCV, and HIV infection. One-hundred thirty-eight (35.1%) individuals did not show any HBV/HCV/HIV serological marker, while 186 (47.3%) were indicative of past or current HBV infection. A total of 42 (10.7%) subjects were HBsAg positive, 59 (15.0%) showed the serological profile "anti-HBc alone", and only 40 (10.1%) were anti-HBs alone. Overall, 22/393 (5.6%) immigrants were anti-HCV positive and 13/327 (4.0%) were infected with HIV. Findings from this study suggest that a suitable screening protocol for the viral blood/sexually transmissible diseases is recommended on entering Italy, and the adoption of health control strategies should also be considered to safeguard the health of the local population.

Fatal fulminant primary hepatitis B virus infections with G1896A precore viral mutants in southeastern France

Fulminant hepatitis has been shown to occur in about 1% of acute hepatitis B virus (HBV) infections, and its mortality rate is nearly 70%. Specific HBV genotypic features have been pointed out in fulminant acute hepatitis B worldwide, but these associations remain controversial. We describe all four primary HBV infections diagnosed in 2008 in our institution in Marseille, southeastern France, including two fatal cases. HBV genotypes were D or E. Precore G1896A HBV mutants were detected in both fatal fulminant primary HBV infections. Hepatitis B surface antigen and hepatitis B e antigen (HBeAg) were negative in two and three cases, respectively, despite HBV DNA detection. Primary HBV infection remains a cause of death in France. The impact of the precore G1896A mutation on the severity of AHB deserves to be assessed in larger studies in this country.

Effect of age on the incidence of acute hepatitis B after 25 years of a universal newborn hepatitis B immunization program in Taiwan

BACKGROUND

Raising concerns about the waning immunity of cohorts receiving hepatitis B virus (HBV) vaccination in infancy persuaded us to identify the changing incidence of acute hepatitis B (AHB) in children and young adults.

METHODS

Data on AHB surveillance through the National Notifiable Disease Surveillance System from July 2001 to June 2009 were collected and described. Cases were divided into 2 cohorts according to their birth year: before or after the universal newborn HBV vaccination program. Age-specific incidence was compared for the 2 birth cohorts with diagnosis at age 15-24 years.

RESULTS

In total, 2226 patients with AHB were identified. AHB rates varied by age; the highest rates occurred among unvaccinated individuals aged 25-39 years (2.33/100 000). Due to breakthrough HBV infection from mother-to-infant transmission, vaccinated infants (0.78/100 000) had higher rates than those aged 1-14 years (0.04/100 000), who had the lowest rates. The incidence in vaccinated birth cohorts was significantly lower than in unvaccinated birth cohorts among patients 15-24 years old, with an adjusted-relative risk of 0.42.

CONCLUSIONS

Implementation of universal-at-birth HBV immunization programs has effectively reduced the occurrence of AHB among adolescents and young adults in Taiwan for >25 years, making infants and the 25-39-year-old cohort additional targets for preventing AHB.

Long-term immunogenicity of hepatitis B vaccination in children and adolescents in a southern Italian town

PURPOSE

Universal anti-hepatitis B vaccination of infants and of 12-year-old children became mandatory in Italy in 1991. The purpose of this study was to evaluate the persistence of anti-hepatitis B surface (HBs) antibodies several years after a primary course of vaccination.

METHODS

In 2010, anti-HBs titers were measured in all subjects aged between 5 and 25 years residing in a southern Italian town. Individuals with an anti-hepatitis B antibody concentration of 10 IU/ml or more were considered to be protected.

RESULTS

Of the 671 subjects evaluated, 149 (30%) lacked protective antibodies. Fifty-three (29.4%) of the subjects had been vaccinated ≤10 years earlier and 96 (30.3%) more than 10 years earlier (P = not significant). Subjects vaccinated in infancy were more likely to lack protective anti-HBs antibodies than subjects vaccinated at 12 years of age, regardless of the years elapsed since immunization.

CONCLUSIONS

Most subjects maintained protective antibodies for a considerable number of years after vaccination. Vaccination in adolescence results in more prolonged immunogenicity than vaccination in infancy.

[Pharmacological treatment of acute hepatitis B]

The incidence of acute B hepatitis is decreasing due to socioeconomical changes and the implementation of vaccination programs. Nevertheless it is potentially severe, causing approximately 30% of acute liver failures in Spain. Pharmacological treatment of acute B hepatitis has become a matter of issue over the last decade. This text offers a review of the published data and international guidelines. Most published studies have a low methodological quality and lamivudine was used as treatment in all of them. A survival improvement with prompt treatment has been shown in acute liver injury and probably in severe acute hepatitis (total bilirubin>10mg/dl and INR>1.5). International guidelines support treatment in these cases, but there is no consensus on the drug to use or the length of treatment.

Successful tenofovir treatment for fulminant hepatitis B infection in an infant

Fulminant hepatic failure is defined by the presence of severe impairment of liver function, with or without encephalopathy, in patients with no underlying chronic liver disease. We report the case of a 4-month-old infant who developed fulminant hepatitis B infection and recovered concomitant with tenofovir therapy without liver transplantation.

Elimination of hepatocellular carcinoma and acute hepatitis B in children 25 years after a hepatitis B newborn and catch-up immunization program

Alaska Native people experience the highest rates of acute and chronic hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) in the United States. We examined the effect of a universal newborn immunization with hepatitis B vaccine and mass population screening immunization program initiated in 1984 on rates of HBV and HCC in children 25 years later. During this time, the population of Alaska Native people grew from an estimated 75,000 to 130,000 persons. A surveillance system to detect acute HBV infection in Alaska Native facilities was established in 1981. Cases of HCC in children under 20 years of age were identified using a National Cancer Institute (NCI)-funded Cancer Registry established in 1969 coupled with an active surveillance program of screening persons with chronic HBV semiannually for alpha-fetoprotein since 1982. The incidence of acute symptomatic HBV infection in persons <20 years of age fell from cases 19/100,000 in 1981-1982 to 0/100,000 in 1993-1994. No cases of acute HBV have occurred in children since 1992. The incidence of HCC in persons <20 years decreased from 3/100,000 in 1984-1988 to zero in 1995-1999 and no cases have occurred since 1999. The number of identified hepatitis B surface antigen-positive children <20 years in the Alaska Native population declined from 657 in 1987 to two in 2008.

CONCLUSION

Universal newborn vaccination coupled with mass screening and immunization of susceptible Alaska Natives has eliminated HCC and acute symptomatic HBV infection among Alaska Native children and this approach is the best way to prevent HBV-related disease in children.

Unawareness of HBV infection among inpatients in a Southern Italian hospital

Hepatitis B virus (HBV) infection may run undetected. Unawareness of an ongoing infection delays the diagnosis of HBV-related liver disease and favours the spread of the virus. We have evaluated among hepatitis B surface antigen-positive (HBsAg) inpatients admitted to a Southern Italian hospital the proportion of those aware of their carrier status and correlated the status to signs of liver disease. All patients admitted to the San Giovanni Rotondo Hospital from March 2008 to July 2009 were tested for HBV and hepatitis C virus (HCV) markers, and those positive for HBsAg were interviewed and underwent examinations for liver function and abdominal ultrasound. Overall, of 25,000 patients admitted during the observation period 311 (1.2%) were positive for HBsAg, most of them (98%) being anti-HBe positive. HCV and HDV co-infections were ascertained in 2.9% and 0.6% of cases, respectively. Two hundred and fifty-three subjects (81%) agreed to undergo further investigation, 132 of them (52%) were HBV-DNA positive. One hundred and two patients (40.3%) were unaware of their infection; this was encountered among 29% of HBV-DNA-positive and 52% of HBV-DNA-negative subjects (P < 0.01). Subjects already aware of their infection were more likely to present with abnormal alanine aminotransferase (ALT) levels (27%vs 15%), serological presence of HBV-DNA (63.6% vs. 36%) and liver cirrhosis (30%vs. 13%). A high proportion of HBsAg-positive patients (40.3%) were unaware of their infection, which had evolved to the stage of liver cirrhosis in a consistent percentage of them.

HBV disease: HBsAg carrier and occult B infection reactivation in haematological setting

HBV reactivation in patients with haematological malignancies undergoing chemoimmunotherapy is a serious and frequent complication. This is linked to either the high frequency of inactive HbsAg carriers and occult B infection among oncohaematological patients or the profound immunosuppression caused by high dose chemotherapy, monoclonal antibody therapy or auto- and allo-haematopoietic stem cell (HSC) transplantations. Identifying the patients at risk is mandatory in this clinical setting and prophylaxis with antiviral drugs or close monitoring may reduce and/or eliminate the HBV reactivation risk and the serious consequences. In general, preemptive anti-HBV therapy is more effective than treatment at reactivation. Prompt lamivudine prophylaxis should be given to HBsAg positive patients (inactive carriers) undergoing chemotherapy-immunochemotherapy and continued after cessation of immunosuppression even though long-term lamivudine therapy involves a risk of developing drug resistance. Use of newer anti-HBV agents may be considered. HBV reactivation has also been observed in occult B infection (HBcAb positive) and the optimal management of this group of patients requires special attention.

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.

Factors affecting the changes in molecular epidemiology of acute hepatitis B in a Southern Italian area

To explore changes in molecular epidemiology of acute viral hepatitis B (AVH-B), hepatitis B virus (HBV) genotypes were determined by direct sequencing of the Pre-S-S region in 123 consecutive patients, with AVH-B observed in Naples or its surroundings in the last decade (group AVH-B) and in 123 HBV chronic carriers [chronic carrier of HBV (CC-B) group] from the same areas, who had been hepatitis B surface antigen-positive for more than 10 years. Genotype D was less frequently detected in patients with AVH-B than in those in the CC-B group (76.4%vs 97.5%, P < 0.0001). In the AVH-B group, intravenous drug addiction (IVDA) was the prevalent risk factor (55.3%) for acquiring HBV in the 94 patients with HBV genotype D, but it was rarely recorded (6.9%) in the 29 patients with genotypes non-D (P < 0.0001); unsafe sexual intercourse was prevalent in patients with genotype non-D (72.3%) and less frequent in those with genotype D (28.8%, P < 0.005). In the AVH-B group, the prevalence of non-D genotypes increased during the observation period from 11.1% in 1999-2003 to 41.1% in 2004-2008 (P < 0.0005), paralleling the increase in the prevalence of patients with unsafe sexual intercourse; similarly, the progressive decrease in IVDA paralleled the decrease in the prevalence of genotype D (from 88.3% in 1999-2003 to 11.7% in 2004-2008). The prevalence of HBV non-D genotypes recorded in the last 10 years in AVH-B in this area shows a progressive increase, most probably because of recent changes in HBV epidemiology, namely, the HBV mass vaccination campaign and increased immigration from areas with high HBV endemicity.

Hepatitis B immunisation programmes in European Union, Norway and Iceland: where we were in 2009?

In January 2009 25 European Union (EU) Member States (MSs), Norway and Iceland, participated in a survey seeking information on national hepatitis B vaccination programmes. Details of vaccination policy, schedule, population groups targeted for vaccination, programme funding, vaccine coverage and methods of monitoring of vaccine coverage were obtained. Twenty (74%) countries reported that they have a universal hepatitis B vaccination programme, in addition to immunisation of at risk groups; seven (26%) countries recommend HBV for high risk groups only (with some inter-country variation on groups considered at high risk). Among countries without universal hepatitis B vaccination programmes, the major factor for non-introduction is low disease endemicity.