Acute hepatitis delta virus infection in Italy: incidence and risk factors after the introduction of the universal anti-hepatitis B vaccination campaign

Acute Delta Hepatitis in Italy spanning three decades (1991-2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come.

Migratory flow and hepatitis delta infection in Italy: A new challenge at the beginning of the third millennium

In Italy, HDV infection endemicity has greatly decreased overtime. Migratory flow may change this scenario as migrants often come from high HDV endemicity areas. Here, we studied characteristics of HDV infection in Italy, particularly addressed to the birth area of subjects. Chronic HBsAg carriers consecutively referring to 9 units in Italy prospectively enrolled for a six-month period in 2019 were tested for anti-HDV by ELISA. Multiple logistic regression analysis was performed to identify anti-HDV positivity independent predictors. A total of 894 HBsAg-positive subjects were enrolled. Of them, 786 (87.9%) were tested for anti-HDV. Anti-HDV overall prevalence was 9.9% (6.4% in Italian natives and 26.4% in non-natives; P < .001). HDV-RNA was checked in 63 (80.8%) of the 78 anti-HDV+ subjects, and 49 (77.8%) tested positive. Compared to non-natives, Italians were more likely males (male/female 1.6 vs 0.6; P < .05) and older (median age 57 years vs 46 years; P < .05). Multivariate analysis showed that non-natives (OR = 6.02; CI 95% = 3.06-11.84) and cirrhosis (OR 9.6; CI 95% = 5.39-17.30) were independently associated with anti-HDV positivity. A remarkable changing pattern in some characteristics of anti-HDV-positive subjects was observed over 1987-2019: a decreasing male/female ratio, an increasing mean age and proportion of cirrhotic subjects. Anti-HDV prevalence decreased from 7.4% to 6.4% among Italians, increasing from 12.2% to 26.4% among non-natives during 2001-2019. Hence, HDV infection in Italians is further decreasing and mostly affects old people and subjects with advanced disease reflecting a survival effect. Conversely, non-natives are sixfold more likely anti-HDV-positive with an increasing trend. Migratory flow may be a new challenge for HDV infection at the beginning of the third millennium.

Hepatitis Delta: Prevalence, Natural History, and Treatment Options

Half a century after its discovery, hepatitis delta remains a pertinent global health issue with a major clinical impact in endemic regions and an underestimated prevalence worldwide. Hepatitis delta virus infection follows a challenging clinical course and is responsible for significant liver-related morbidity. Although the only currently available treatment (pegylated interferon) does not provide consistent results, emerging therapeutic options are promising. This article explores the epidemiology, natural history, as well as current and potential therapeutic options for hepatitis delta virus infection.

A review on hepatitis D: From virology to new therapies

Hepatitis delta virus (HDV) is a defective virus that requires the hepatitis B virus (HBV) to complete its life cycle in human hepatocytes. HDV virions contain an envelope incorporating HBV surface antigen protein and a ribonucleoprotein containing the viral circular single-stranded RNA genome associated with both forms of hepatitis delta antigen, the only viral encoded protein. Replication is mediated by the host cell DNA-dependent RNA polymerases. HDV infects up to72 million people worldwide and is associated with an increased risk of severe and rapidly progressive liver disease. Pegylated interferon-alpha is still the only available treatment for chronic hepatitis D, with poor tolerance and dismal success rate. Although the development of antivirals inhibiting the viral replication is challenging, as HDV does not possess its own polymerase, several antiviral molecules targeting other steps of the viral life cycle are currently under clinical development: Myrcludex B, which blocks HDV entry into hepatocytes, lonafarnib, a prenylation inhibitor that prevents virion assembly, and finally REP 2139, which is thought to inhibit HBsAg release from hepatocytes and interact with hepatitis delta antigen. This review updates the epidemiology, virology and management of HDV infection.

Prevalence and epidemiology of hepatitis D among patients with chronic hepatitis B virus infection: a report from Northern Spain

BACKGROUND

The incidence of hepatitis delta virus (HDV) infection has decreased during the last decades. However, an increasing trend has been reported recently.

PATIENTS AND METHODS

We carried out a case-control study to analyze changes in its prevalence in 1215 chronic hepatitis B virus (HBV) patients, diagnosed consecutively in a tertiary center, between 1983 and 2012. According to the year of diagnosis, patients were distributed into two groups: A [1983-1997 (n=786)] and B [1998-2012 (n=429)].

RESULTS

The prevalence of anti-HDV was 8.2% (9.4% in group A and 6.1% in group B) (P=0.04). Multivariate regression revealed that intravenous drug use [odds ratio (OR) 261.0; 95% confidence interval (CI), 28.7-2368.5; P<0.001], blood transfusion (OR 28.0; 95% CI, 2.7-295.9; P=0.03), anti-HIV(+) (OR 4.8; 95% CI, 1.6-14.5; P=0.004), and high alanine aminotransferase (OR 14.4; 95% CI, 3.4-60.6; P<0.001) were associated independently with the presence of anti-HDV in group A, whereas in group B, it was associated with immigration (OR 20.0; 95% CI, 4.7-84.9; P<0.001), intravenous drug use (OR 683.5; 95% CI, 52.7-8855.7; P<0.001), promiscuous sexual activity (OR 22.6; 95% CI, 2.2-228.5; P=0.008), and high alanine aminotransferase (OR 3.4; 95% CI, 1.1-10.0; P=0.02).

CONCLUSION

Although a significant decrease in the prevalence of HDV infection has been observed, it is still above 5%. Immigration and sexual transmission have emerged as new risk factors for HDV infection.

Hepatitis delta infection in Italian patients: towards the end of the story?

BACKGROUND

The endemicity of hepatitis delta virus infection in Italy has decreased in the last decades.

AIM

To evaluate the current epidemiology of chronic delta infection in Italy and to compare the present findings with the corresponding figures from the previous studies.

METHODS

A cross-sectional study involving 16 referral centres scattered all over the country in 2014.

RESULTS

Out of the 513 hepatitis B surface antigen-positive subjects enrolled, 61 (11.9%) were anti-delta positive, with a sex ratio (M/F) of 2.05. The majority (80.3%) of them was 50 years or older, while the proportion of subjects younger than 30 years of age was as low as 3.3%. No difference was detected by geographical area of residence. The presence of liver cirrhosis was diagnosed in 52.4% of cases. In comparison to previous studies, a further shift towards the oldest age groups and an increasing proportion of subjects having liver cirrhosis among all anti-delta-positive subjects are observed.

CONCLUSIONS

Currently, hepatitis delta infection mostly affects old people who have an advanced but indolent liver disease, reflecting a survival effect. The defective hepatitis delta virus is near to disappear in the country, where it has been discovered in the second half of 70s.

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.

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.

Hepatitis B and D viruses replication interference: Influence of hepatitis B genotype

AIM: To study the hepatitis B virus (HBV) and hepatitis D virus (HDV) replication interferences in patients with chronic hepatitis delta infected with different HBV genotypes.

METHODS: We conducted a transversal study including 68 chronic hepatitis delta (CHD) (37 HIV-positive) patients and a control group of 49 chronic hepatitis B (CHB) (22 HIV-positive) patients. In addition, a dynamic follow-up was performed in 16 CHD patients. In all the samples, the surface antigen of hepatitis B (HBsAg) serum titers were analyzed with the Monolisa HBsAg Ultra system (Bio-Rad), using as quantification standard a serial dilution curve of an international HBsAg standard. Serum HBV-DNA titers were analyzed using the Roche Cobas TaqMan (Roche, Barcelona, Spain), and the serum HDV-RNA using an in-house real-time qRT-PCR method, with TaqMan probes. HBV genotype was determined with the line immunoassay LiPA HBV genotyping system (Innogenetics, Ghent, Belgium). In those patients negative for LiPA assay, a nested PCR method of complete HBsAg coding region, followed by sequence analysis was applied.

RESULTS: No differences in the HBV-DNA levels were found in CHB patients infected with different HBV genotypes. However, in CHD patients the HBV-DNA levels were lower in those infected with HBV-A than in those with HBV-D, both in HIV negative [median (IQR): 1.25 (1.00-1.35) vs 2.95 (2.07-3.93) log₁₀ (copies/mL), P = 0.013] and HIV positive patients [2.63 (1.24-2.69) vs 7.25 (4.61-7.55) log₁₀ (copies/mL), P < 0.001]. This was confirmed in the dynamic study of the HBV/HDV patients. These differences induce an under-estimation of HBV-A incidence in patients with CHD analyzed with LiPA assay. Finally, the HBsAg titers reflected no significant differences in CHD patients infected with HBV-A or D.

CONCLUSION: Viral replication interference between HBV and HDV is HBV-genotype dependent, and more evident in patients infected with HBV-genotype A, than with HBV-D or E.

Hepatitis D Virus Infection Among Hepatitis B Surface Antigen Carriers and in "Isolated anti-HBc" Antibodies Profile in Central Tunisia

BACKGROUND

Hepatitis D Virus (HDV) causes accelerated liver diseases in patients with Hepatitis B Virus (HBV) infection. There is lack of data about its prevalence, related risk factors and interaction with HBV carriers in our country.

OBJECTIVES

The aim of this study was to estimate the prevalence of hepatitis delta and associated risk factors among Hepatitis B surface antigen (HBsAg) and "isolated anti-HBc" profile carriers in central Tunisia.

PATIENTS AND METHODS

In this cross-sectional study, 540 patients with positive HBsAg and 109 "isolated anti-HBc" profile receiving care in a teaching hospital were tested for the presence of HDV serum-markers using commercially available enzyme immunoassay kit. HBV-DNA was detected by nested PCR in "isolated anti-HBc" profile group.

RESULTS

Prevalence of HDV was 8.1% in HBsAg carriers group, but it was significantly higher in active than inactive hepatitis (30.2% and 4.5%, respectively, OR = 9, 95% CI: [4.48-18.58]). There was no significant association between studied risk factors and HDV infection. In the "isolated anti-HBc" profile group, prevalence of HDV was 4.6% and HBV-DNA had negative result in all patients with positive results for HDV.

CONCLUSIONS

Although HDV had low prevalence in our area, it is vital to plan preventive strategies for HDV spread as well as HBV prevention. It is particularly important to suspect HDV infection in active HBV carriers to manage a particularly severe dual infection. HDV infection should be suspected even in negative HBsAg patients having "isolated anti-HBc" profile.

Hepatitis B and elders: An underestimated issue

As the world's population becomes older, the burden of hepatitis B virus in elderly has to be considered. The liver changes with aging and its function is eventually altered. The prevalence of hepatitis B virus is paradoxically more important in elderly in areas having vaccination programs, because of a loosening of the prevention in older patients. Some differences in hepatitis B presentation must be enhanced in elderly: lower spontaneous hepatitis B surface antigen clearance after a recent contamination, major risk of cirrhosis and hepatocarcinoma. Acute hepatitis B seems to be more often symptomatic, with a great risk of chronicity. Hepatocarcinoma linked to hepatitis B virus has a higher prevalence and a different presentation in elderly. Its treatment is the same as in younger people but is less often possible. Liver transplantation is contraindicated after 70 years old. Hepatitis B treatment panel is the same as in younger people (pegylated interferon, nucleoside or nucleotide agents). It gives identical results with no particular adverse events if the precautions for use are followed. Vaccination is less efficient, as in immunocompromised patients, and needs specific protocols.

Hepatitis D in Children

Hepatitis D virus (HDV) is an uncommon, defective, single-stranded circular RNA virus that is dependent on the hepatitis B virus' surface antigen envelope proteins for transmission. It is highly pathogenic and associated with high rates of progression to cirrhosis and associated complications. HDV continues to ravage endemic parts of Asia and Europe, and its prevalence in the United States, although low, has not decreased in frequency, despite universal hepatitis B virus vaccination, because of lack of testing and underrecognition. There are few reports on the prevalence and characteristics of HDV infection in the pediatric population. We present 2 patients with HDV infection at our institution; both were from eastern Europe and were treated with pegylated interferon-α. The present standard of care treatment for HDV yields suboptimal results, but insights into the virology of hepatitis D are stimulating the search for novel therapeutic approaches, particularly the development of prenylation inhibitors and viral entry inhibitors.

Therapy of acute and fulminant hepatitis B

Although new hepatitis B virus (HBV) infections are decreasing due to improving vaccination coverage, patients without vaccination coverage can still suffer from manifestation of acute hepatitis B with jaundice and (although rarely) liver failure. No treatment is indicated for mild acute hepatitis B; however, antiviral therapy should be initiated for patients showing signs of significant liver impairment as exemplified by deterioration of prothrombin time to an equivalent of 1.5 or 50% of the 'Quick test'. For fulminant hepatitis, there is no complete agreement on whether antiviral treatment would alter the course, but it should still be started, as it would reduce the risk of reinfection in case there is a need for liver transplantation. Patients in danger of progression towards acute liver failure should be referred to transplant centers as early as possible.

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.

Hepatitis D virus infection in the Western Brazilian Amazon - far from a vanishing disease

INTRODUCTION

A decline in hepatitis D virus (HDV) occurrence was described in Europe and Asia. We estimated HDV prevalence in the Brazilian Amazon following hepatitis B vaccination.

METHODS

This is a cross-sectional survey of HDV measured by total antibodies to HDV (anti-HD T).

RESULTS

HDV prevalence was 41.9% whiting HBsAg carries and was associated with age (PR = 1.96; 95% CI 1.12-3.42; p = 0.01), hepatitis B virus (HBV) infection (PR = 4.38; 95% CI 3.12-6.13; p < 0.001), and clinical hepatitis (PR =1.44; 95% CI 1.03-2.00; p = 0.03). Risk factors were related to HDV biology, clinical or demographic aspects such as underlying HBV infection, clinical hepatitis and age.

CONCLUSIONS

Our study demonstrated that HDV infection continues to be an important health issue in the Brazilian Amazon and that the implementation of the HBV vaccination in rural Lábrea had little or no impact on the spread of HDV. This shows that HDV has not yet disappeared from HBV hyperendemic areas and reminding that it is far from being a vanishing disease in the Amazon basin.

A re-assessment of the epidemiology and patient characteristics of hepatitis D virus infection in inner city London

OBJECTIVES

To re-assess the prevalence and patient characteristics of hepatitis D virus (HDV) infection among hepatitis B patients in inner city London.

METHODS

All hepatitis B patients attending clinics over a 52 months period were tested for HDV antibody. All reactive samples were also tested for anti-HDV IgM and RNA. The characteristics of HDV seronegative patients first seen in the calendar year 2008 were compared with all HDV seropositive patients in the cohort.

RESULTS

Of 1048 hepatitis B patients, 11 had equivocal anti-HDV serology (1%) and 22 were HDV seropositive (2.1%, 95%CI 1.39-3.16%); 12 were anti-HDV IgM positive and 15 HDV RNA positive. No patient with equivocal anti-HDV serology had detectable HDV RNA. Five HDV seropositive patients were intravenous drug users (22.7%); 17/22 were from abroad with 11/22 (50%) from sub-Saharan Africa. HDV seropositive patients had poorer laboratory parameters and were more likely to have evidence of cirrhosis. Triple infected (HIV/HBV/HDV) patients were also more likely to have cirrhosis than HIV/HBV dually infected patients.

CONCLUSIONS

The prevalence of HDV in hepatitis B patients in inner city London was about 2%. The role of migration from endemic countries should be recognised.

Epidemiology of hepatitis D virus (HDV) infection in an urban area of northern Italy

OBJECTIVES

The introduction of vaccination against hepatitis B initially reduced the number of HBV (hepatitis B virus) and HDV (hepatitis delta virus) infections, but the decreasing trend of HDV infection seems to have stopped. The aim of this study was to assess the prevalence of HDV infection in the general population living in the catchment area of Legnano Hospital in northern Italy.

METHODS

Of the 22,758 subjects tested in 2007-2008, the 488 who were HBsAg (hepatitis B surface antigen)-positive [including 107 (21.9%) of non-Italian origin] were subsequently tested for anti-HDV antibodies.

RESULTS

Of the 488 subjects who tested positive for HBsAg, 24 (4.9%) were anti-HDV positive, all aged between 30 and 60 years. The difference in prevalence between males (7.1%) and females (1.9%) was statistically significant (p < 0.05), but not that between Italian (5.0%) and non-Italian patients (4.7%). The differences in anti-HDV seropositivity between the patients with acute (0%) and chronic infections (6.3%), and between the incident (2.5%) and prevalent cases (7.4%), were not statistically significant, but there was a significant difference (p < 0.01) between those with asymptomatic (2.1%) and clinically symptomatic infections (10.3%). Intravenous drug abuse was the main source of infection.

CONCLUSIONS

In the catchment area of our hospital, the prevalence of HDV infection does not seem to be due to patients of non-Italian origin, but to Italian patients who are not vaccinated against HBV and who survived the HDV epidemic of the 1970s and 1980s. Nevertheless, the increase in the number of immigrants from non-EU countries in recent years is soon likely to lead to a change in the epidemiology of HDV.

Current hepatitis delta virus type 1 (HDV1) infections in central and eastern Turkey indicate a wide genetic diversity that is probably linked to different HDV1 origins

Hepatitis delta virus (HDV) is a subviral pathogen of humans, a satellite of hepatitis B virus (HBV) that induces severe acute and chronic liver diseases. The genus Deltavirus consists of eight clades or genotypes, with HDV1 being ubiquitous and frequently characterized. In Turkey, HDV1 infection is highly endemic among HBsAg carriers, especially in the southeastern region. In this study, we analyzed 34 samples from patients who were chronically infected with HBV/HDV, originating from 22 cities of rural regions in the central and eastern parts of Turkey, in order to determine the levels of viral replication and genetic diversity. HDV RNA levels ranged between 3.02 and 8.75 Log copies/mL, and HBV DNA was detected in 25 samples (73.5%), with values ranging from 2.53 to 5.30 Log copies/mL. Analysis of nucleotides 900-1280 of HDV genomes (n = 34) and full-length (n = 17) sequences indicated that all of the strains belonged to genotype HDV1. However, a high genetic diversity was observed among the isolates, with a mean full-length dissimilarity score of 13.05%. HDV sequences clustered with sequences from Western Europe (n = 11), Eastern Europe and Asia (n = 19) or Africa (n = 4). HDV1 isolates related to strains of African origin had a serine residue instead of an alanine at position 202 of the large delta protein. HBV preS1 sequences obtained for 34 isolates indicated an HBV/D genotype in all cases. Taken together, our results indicate that in Turkey, where HBV-HDV dual infection is highly endemic, both viruses have high levels of replication, and HDV strains exhibit wide genetic diversity, which might reflect ancient evolution and/or successive outbreaks.

Clinical outcome of acute and chronic hepatitis delta over time: a long-term follow-up study

Long-term changes in the frequency and outcome of hepatitis delta virus (HDV) infection have seldom been analysed. This retrospective, longitudinal study includes 398 consecutive hepatitis B surface antigen (HBsAg)-positive patients with anti-HDV antibodies who attended our institution between 1983 and 2008. At enrolment, 182 patients had acute and 216 chronic hepatitis. Patients were grouped into two periods. Those who attended between 1983 and 1995 and those between 1996 and 2008. The former group was significantly younger, mainly intravenous drugs users, and had a greater incidence of acute HDV and HIV and HCV coinfection. Patients with acute HBV/HDV coinfection cleared both infections in 90% of cases, while all patients with HDV superinfection evolved to chronic disease. One hundred and fifty-eight patients with chronic HDV were followed for a median period of 158months. Seventy-two per cent of the patients remained stable, 18% had hepatic decompensation, 3% developed hepatocellular carcinoma, and 8% cleared HBsAg. Liver-related death was observed in 13% of patients and mainly occurred in patients from the first period (P=0.012). These results indicate an outbreak of HDV at the end of the 1980s and the beginning of the 1990s, with a large number of acute HDV cases affecting predominately young, male intravenous drug users. Currently, patients with chronic HDV disease are older, and factors associated with worse prognosis include the presence of cirrhosis and age at the time of diagnosis.

The prevalence of hepatitis B virus markers in a cohort of students in Bangui, Central African Republic

BACKGROUND

Hepatitis B virus (HBV) is the major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. The global epidemiological scenario of HBV infection has been changing rapidly over the last two decades due to an effective immunization programme initiated by the World Health Organization. The objective of this study is to estimate the prevalence of HBV in apparently healthy young people and to identify the risk factors of transmission of the HBV among this population in Bangui.

METHODS

Dried blood Spots from 801 adolescent high school and young adult university students were prepared by spotting a drop of whole blood (4 spots) from the same fingerprick onto Whatman filter paper. A blood sample aliquot eluted from DBS was then processed with commercial ELISA tests (Abbott Murex, Dartfort, UK) to detect HBsAg antigen, Anti-HBc and Anti-HBs antibodies).

RESULTS

The overall prevalence was 42.3% for antibody to hepatitis B core antigen, 15.5% for HBsAg of which 1.3% of HBsAg alone. HBV familial antecedents, sexual activity and socioeconomic conditions were the main risk factors of HBV infection encountered in the adolescents and young adults.

CONCLUSION

These results show for the first time the high prevalence of HBV in apparently healthy young people in Bangui. This high prevalence is age- and sex-independent. Transmission risk factors were a familial antecedent of HBV, no utilisation of condoms and public scholarship. To lower HBV prevalence, an adequate program of active screening and vaccination for adolescents and young adults should be implemented, along with a universal immunization program.

Epidemiology, pathogenesis and management of hepatitis D: update and challenges ahead

Hepatitis D is caused by infection with the hepatitis D virus (HDV) and is considered to be the most severe form of viral hepatitis in humans. Hepatitis D occurs only in individuals positive for the HBV surface antigen (HBsAg) as HDV is a defective RNA viroid that requires HBsAg for transmission. At least eight different HDV genotypes have been described and each has a characteristic geographic distribution and a distinct clinical course. HDV and HBV coinfection can be associated with complex and dynamic viral dominance patterns. Chronic HDV infection leads to more severe liver disease than HBV monoinfection and is associated with accelerated fibrosis progression, earlier hepatic decompensation and an increased risk for the development of hepatocellular carcinoma. So far, only IFN-alpha treatment has proven antiviral activity against HDV in humans and has been linked to improved long-term outcomes. Studies conducted in the past 2 years on the use of PEG-IFN-alpha show that a sustained virologic response to therapy, measured in terms of undetectable serum HDV RNA levels, can be achieved in about one quarter of patients with hepatitis D. Novel alternative treatment options including prenylation inhibitors are awaiting clinical development for use in hepatitis D.

Hepatitis B vaccination: The key towards elimination and eradication of hepatitis B

Hepatitis B virus infection is a global health problem. Worldwide, about 360 million people are chronically infected with the virus. They continue to spread the virus to others and are themselves at risk of chronic liver diseases and hepatocellular carcinoma. The infection can now be treated by antivirals or interferons and the transmission route can be interrupted. Nevertheless, the most effective means is to immunize all susceptible individuals, especially young children, with safe and efficacious vaccines. The combined efforts of vaccination, effective treatment and interruption of transmission make elimination of the infection plausible and may eventually lead to eradication of the virus. Because hepatitis B vaccination has a key role in the control of hepatitis B, properties of this vaccine, its effectiveness in pre-exposure and post-exposure settings, duration of protection after vaccination and the need of booster doses are discussed. Mass hepatitis B vaccination in children decreases the carriage of the virus, and the diseases associated with acute and chronic infection, including hepatocellular carcinoma. Challenges that need to be solved to expand mass vaccination, and the strategies towards elimination and eventual eradication of hepatitis B in the world are also discussed.

Hepatitis D: the comeback?

Hepatitis D virus (HDV) infection has considerably diminished in Europe since the 1970-1980s. The prevalence rates of chronic hepatitis D in HBsAg carriers in Italy have declined from 25% at the beginning of the 1980s to 8% in the 1990s. Similar declines in prevalence have been reported in Spain, Taiwan and Turkey. Better public health standards, HBV vaccination and the effect of measures to control the spread of human immunodeficiency virus have brought about a decline in the numbers of HBsAg carriers and therefore a decline in the HBV-dependent HDV. However, HDV has not declined further in Europe in the last decade, as the pool of fresh infections in migrants from HDV-endemic areas is counterbalancing the shrinking cohort of long-standing domestic infections acquired in the epidemic of the 1970-1980s. Hepatitis D remains an important health problem outside Europe, and new foci of infection continue to be identified in developing countries.

Current issues in adolescent immunization

Based on the December 2006 Fondation Mérieux International Scientific Symposium, the current state of adolescent immunization is reviewed with a focus on the policy and programmatic issues that impact the acceptability, initiation, and successful implementation. Key questions are identified with proposed strategies to help achieve successful adolescent immunization programs. The role of current vaccines targeted to adolescents, such as those directed against invasive meningitis, pertussis, and the human papillomavirus, is reviewed as well as their role in rejuvenating interest in adolescent immunization, and more importantly, adolescent health as a whole.

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

BACKGROUND

Italy had intermediate-level endemicity for hepatitis B virus (HBV) infection in the 1970s and 1980s. In 1991, vaccination of infants and adolescents became mandatory. We report the impact of universal vaccination 14 years after its beginning.

METHODS

We performed a case-control study within a population-based surveillance for acute viral hepatitis. The incidence of acute hepatitis B (AHB) was estimated for the time since 1991, and the association between AHB and the considered risk factors was analyzed for the period 2001-2005.

RESULTS

The incidence of AHB progressively decreased from 1991 to 2005, mainly for persons in the age groups targeted by the universal vaccination campaign: there was a 24-fold and 50-fold decrease in the 15-24-year and 0-14-year age groups, respectively; for the > or =25-year age group, the incidence halved. Owing to the persons' ages, approximately 3% of total AHB cases should have been the target of vaccination campaign. In 2004-2005, foreigners accounted for 14% of total cases and for 57% of persons who should have been targets for vaccination. Missed opportunities for immunization were documented for approximately 50% of patients with AHB who reported cohabitation with HBV carriers and for 70% of those who reported injection drug use. The strongest associations with AHB were found for blood transfusion (adjusted odds ratio [OR(adj)], 8.4; 95% confidence interval [CI], 2.7-26), cohabitation with HBV carriers (OR(adj), 5.3; 95% CI, 3.6-7.7), injection drug use (OR(adj), 3.8; 95% CI, 2.5-5.8), and unsafe sexual practices (OR(adj), 2.8; 95% CI, 1.9-4.2).

CONCLUSION

Universal vaccination has contributed to a decreasing AHB incidence in Italy, especially by reducing the risk of infection among persons aged 15-24 years. Most infections occur in persons aged > or =25 years in association with injection drug use, unsafe sexual activity, percutaneous treatment, and iatrogenic exposure. Improvement of vaccine coverage in high-risk groups and adherence to infection control measures during surgery and percutaneous treatment are needed. The high risk still associated with blood transfusion needs to be further investigated, with consideration of occult HBV infection in blood donors. The potential spread of HBV infection from the immigrant population deserves adequate health policy prevention programs.

Chronic hepatitis B in Italy: new features of an old disease--approaching the universal prevalence of hepatitis B e antigen-negative cases and the eradication of hepatitis D infection

We evaluated 1336 hepatitis B surface antigen-positive subjects consecutively observed in 79 Italian hospitals over a 6-month period. The proportion of hepatitis B e antigen-negative cases was 86.4%, that of patients coinfected with hepatitis D virus was 9.7%, and the rate of patients coinfected with hepatitis C virus was 16.8%. Multiple logistic regression analysis showed that age >49 years, alcohol abuse, and anti-hepatitis D virus and anti-hepatitis C virus positivity were independent predictors of progression to liver cirrhosis.

Review article: vaccination and viral hepatitis - current status and future prospects

BACKGROUND

Viral hepatitis is the most common cause of liver disease in the world. In the past 25 years, vaccines have become available for two of the five hepatitis viruses, and, where implemented, vaccination has become a key component of hepatitis prevention.

AIMS

To provide an update on recent advances in the use of current hepatitis vaccines and to examine progress in the development of vaccines for the remaining hepatitis viruses.

METHODS

A Medline search was undertaken to identify the recent relevant literature. Search terms included hepatitis vaccines, hepatitis vaccination and hepatitis A-E vaccines.

RESULTS

Dramatic vaccine-induced declines in the incidence of both hepatitis A and B have occurred in the USA. Strategies to integrate hepatitis A vaccine into universal childhood immunization are being adopted. Similarly, strategies with the goal of eliminating transmission of hepatitis B have been promulgated. A vaccine for hepatitis E has been reported to be effective and safe, but progress in the development of vaccines for hepatitis C and D has been limited.

CONCLUSION

During the next few decades, the goals of eliminating hepatitis A and B virus transmission may be reached in the USA and elsewhere.