HBV whole-genome mutation profile in HIV-1/HBV coinfected patients in a long-term follow-up study.

PURPOSE: Human immunodeficiency virus (HIV-1)-infected patients frequently harbour hepatitis B and C viruses (HBV and HCV, respectively). Possible modifications of the natural history of hepatitis B may occur. The aim of this study was to characterise HBV diversity and evolutionary and mutational viral genome profiles in HIV-1/HBV coinfections. METHODS: HIV-1 and HBV markers determinations (Roche, FRG; Abbott, USA) and HBV genome-length retrospective analysis were performed in follow-up isolates from patients who were either stably HBsAg-negative with a low level of HBV DNA (occult hepatitis B infection, OBI) or HBsAg-positive with a high level of HBV DNA. Phylogenetic analysis (maximum likelihood method, MEGA5), statistical analysis and evolutionary rates calculation (d S/d N) were applied. RESULTS: Positive selection pressures in the PreS/S region and a significantly higher number of mutations in this region including the major hydrophilic region (MHR) and the "a" determinant were shown in HBsAg-negative (possibly OBI) compared to stably HBsAg-positive HIV-1/HBV subgenotypes D3/A2 coinfected patients. Mutants previously described in HIV-1/HBV coinfected patients were found. Known mutants Y100C, P127T and P120A associated to Y134H and S143T and new S mutants, which may potentially affect HBsAg expression and secretion and anti-HBs binding, were detected in baseline sera persisting up to the end of 9 years follow-up. Known mutations of BCP, Pre-C, C and X regions were also characterised. Natural mutants strictly known as being involved in diagnostic failure were not detected; however, numerous corresponding sites showed amino acid variations. CONCLUSIONS: Evolutionary and genotypic differences observed, particularly in the PreS/S region, between HBsAg-negative (OBI) and HBsAg-positive HIV-1/HBV coinfected patients, may contribute, in association with mutations of other genomic regions, to the HBsAg-negative phenotype.

Hepatitis E virus and hepatitis A virus exposures in an apparently healthy high-risk population in Italy.

PURPOSE: The prevalence of anti-hepatitis E virus (HEV) and anti-hepatitis A virus (HAV), as well as the possible links with socio-demographic and other viral risks factors, were evaluated in an inmates population. METHODS: The study population consisted of 973 consecutively recruited inmates of eight Italian prisons. RESULTS: The anti-HEV prevalence was 11.6 % (113/973). It increased significantly by age (χ(2) for linear trend: p = 0.001) and was significantly higher among non-Italian compared to Italian inmates (15.3 vs. 10.7 %, respectively). Age >40 years [odds ratio (OR) 2.1; 95 % confidence interval (CI) 1.4-3.1], non-Italian citizenship (OR 1.8; 95 % CI 1.1-2.9) and anti-HIV seropositivity (OR 2.2; 95 % CI 1.2-4.2) were the only factors independently associated to anti-HEV positivity by logistic regression analysis. The overall anti-HAV prevalence was 86.4 %, and was significantly higher in non-Italian compared to Italian prisoners (92.6 vs. 84.9 %, respectively; p = 0.02). Age older than 40 years (OR 3.6; 95 % CI 2.2-5.9), <5 years formal education (OR 2.1; 95 % CI 1.3-3.2) and non-Italian nationality (OR 2.7; 95 % CI 1.5-4.8) were factors independently associated to anti-HAV positivity by the logistic regression analysis. CONCLUSIONS: Compared to the general population, significantly higher anti-HEV and anti-HAV prevalences were observed in an inmates population in Italy. Old age and non-Italian nationality were factors independently related to both HEV and HAV exposures. This data suggest the important role of low socio-economic factors in the transmission of both infections in high-risk populations. The possible epidemiological and/or pathogenetic links between HEV and HIV exposures need to be studied further.

Virological and epitope evolution of HCV infection from acute hepatitis C to subsequent episodes of HCV-related acute liver cell necrosis.

AIM: To evaluate the virological and clinical events occurring during a 3-year follow-up in three patients who, after symptomatic acute hepatitis C (AHC), experienced subsequent episodes of HC virus (V)-related acute liver cell necrosis. PATIENTS AND METHODS: The three patients were investigated for viral variability in the core, E1/E2, and NS5b regions during different phases of infection, and a computer-assisted analysis of the variation of known predicted epitopes in the consensus sequence was performed. RESULTS: The first patient showed numerous genetic variations, which may be related to the maintenance of a chronic HCV infection state and to episodes of liver disease exacerbation. The second patient showed minimal viral variations associated with apparent resolution of the infection, but the same virus isolate, based on phylogenetic analysis, produced a second acute episode after the occult phase. The third patient, after the resolution of AHC, manifested a second episode of HCV infection by a different HCV sub-genotype. CONCLUSION: Episodes of HCV-related acute liver cell necrosis after AHC may be associated to different virological patterns, such as the establishment of a chronic HCV infection, a reactivation of an occult virus, or a reinfection by a different HCV genotype.

Kinetics of WHV-HDV replication in acute fatal course of woodchuck hepatitis.

The objective of this study was to evaluate, by developing one-step real-time PCR, the outcome of superinfection with hepatitis D virus (HDV) genotype I in woodchucks that were chronic carriers of woodchuck hepatitis virus (WHV) and did not show relevant signs of liver damage. Three woodchucks (Marmota monax) chronically infected with WHV were superinfected with a woodchuck HDV inoculum. The evolution of the WHV and HDV infections was monitored by quantifying HDV-RNA, WHV-DNA, and HDV-WHV antigens and antibodies. WHV and HDV sequencing was also performed and liver markers were evaluated. Liver damage was assessed using the Ishak method. All woodchucks showed a high HDV viral load, antigenemia and short survival after superinfection. Histopathological examination of autoptic liver samples showed massive liver necrosis compatible with an acute fatal course of hepatitis. The WHV sequencing showed that the virus population was not substituted by the WHV inoculum. The HDV sequencing performed during superinfection and at autopsy indicated amino acid changes in immune dominant regions of the HDV antigen. The strong correlation between acute infection with HDV genotype I and rapid and fatal liver failure indicates that HDV can be an important factor in the prognosis of HDV-WHV-superinfected woodchucks.

Activation of the ER stress gene gadd153 by hepatitis C virus sensitizes cells to oxidant injury.

HCV induces endoplasmic reticulum (ER) stress which correlates with transcriptional induction of ER stress genes. Previously, we reported that expression of HCV structural proteins activates the ER stress and pro-apoptotic gene gadd153 which plays a relevant role in cell death induced by oxidative stress. In the present study, using human hepatic cell lines Huh7 carrying a full-length HCV replicon, we demonstrated that replication and expression of the complete set of HCV proteins were associated with elevated expression of gadd153. Analysis of gadd153 promoter activity revealed that both the ATF4 and the ATF6 pathways, which are typically induced during ER stress response, contribute to the induction of gadd153 in HCV replicon cells. Activation of the ATF4 pathway was confirmed by identification of increased levels of ATF4 protein in replicon cells. Importantly, we showed that, following H2O2 treatment, gadd153 gene reached higher levels of expression in replicon cells. Consistent with the marked induction of the pro-apoptotic gene gadd153, HCV replicon cells showed an increased vulnerability to oxidant injury. Treatment of replicon cells with a specific small interfering RNA, targeted to gadd153 gene, reduced basal expression of gadd153 and decreased cell death following H2O2. These findings suggest that gadd153 may play a major role in sensitivity of HCV replicon cell to oxidative stress.

HIV, HTLV-1, and HBV infections in a cohort of Italian intravenous drug abusers: analysis of risk factors.

A seroepidemiological survey of a group of 291 intravenous drug abusers (IVDAs), 45 household contacts of IVDAs, and 39 laboratory workers has been carried out to determine the prevalence of HIV-1, HIV-2, HTLV-1, and HBV antibodies in the sera, as well as to evaluate the role of various risk factors. Among i.v. drug abusers, the prevalence was 32.3% for HIV-1 and 6.6% for HTLV-1. For both viruses, the total figures did not significantly change from 1985 through 1987, accounting for a slow viral circulation in this group. No seropositivity (HIV-1, HTLV-1) was found among laboratory workers, whereas one subject was found seropositive for HIV-1 among household contacts. From 1985 to 1986, 5 out of 58 subjects seronegative for HIV-1 and 5 out of 82 seronegative for HTLV-1 seroconverted (incidence rates of 8.6 and 6.1%, respectively). From 1986 to 1987, none out of 11 seronegatives for HIV and 1 out of 16 seronegatives for HTLV-1 seroconverted. The total figures for hepatitis B markers were 79.2% among IVDAs, 24.4% among household contacts, and 25.6% among laboratory workers. A significant correlation was found between presence of HBV markers and seropositivity for HIV and HTLV-1. A significant association with HIV-1 seropositivity was found for history of sexual intercourse with HIV-1 seropositive partners and for sexual promiscuity. These data emphasize the important role played by sexual behavior in addition to needle-sharing in the spreading of multiple infections among drug abusers.

Hepatitis B and C viruses, human T-cell lymphotropic virus types I and II, and leukemias: a case-control study. The Italian Leukemia Study Group.

The relationship between acute myeloid leukemia (AML), acute lymphocytic leukemia, chronic myeloid leukemia (CML), and refractory anemia with excess of blasts (RAEB) and antibodies to human T-cell lymphotropic virus types I and II (HTLV-I and HTLV-II), and hepatitis B virus and hepatitis C virus (HCV) was investigated in a multicenter case-control study. There were 431 cases enrolled in the study at the time of diagnosis of hematological malignancies, and 862 controls ages 15 years or older were recruited in three hospitals. Antibodies to HTLV-I and HTLV-II, antibody to HCV, hepatitis B surface antigen, and antibody to hepatitis B core antigen were assayed. All cases and controls were negative for HTLV-1 antibodies; one case (1 of 431; 0.2%), and one control (1 of 862; 0.1%) were found positive for HTLV-II antibodies. A nonsignificant excess of risk for hepatitis B surface antigen was present among RAEB cases (odds ratio, 2.40; 95% confidence interval, 0.46--12) CML, (odds ratio, 2.70; 95% CI, 0.86--8.43), and between antibody of hepatitis B core antigen and AML (odds ratio, 1.40; 95% CI, 0.93-2.10). A weak, nonsignificant association was present between AML, acute lymphocytic leukemia, RAEB, and antibody to HCV. These preliminary results suggest a possible association (elevated odds ratios) between hepatitis B virus, AML, RAEB, and CML. However, because all confidence intervals overlapped the null value, these findings need to be confirmed in larger case-control studies.

Induction of FAS ligand expression in a human hepatoblastoma cell line by HCV core protein.

Tumour cells and virus infected cells expressing Fas ligand (FasL) can evade immune surveillance by inducing apoptosis in T cells expressing Fas. In order to characterise a possible role of hepatitis C virus (HCV) core protein in similar mechanisms during HCV infection, we investigated Fas ligand expression and activity in a human hepatoblastoma cell line (HepG2) constitutively expressing this protein. Strong FasL induction was detected by immunoblotting and flow cytometry analysis in the core expressing cell lines Hep39. In contrast, vector transfected cells or cell lines expressing HCV E1-E2 proteins did not show FasL expression. Co-cultivation experiments of Hep39 cells with a Fas-sensitive T cell line indicated that FasL induced by the core protein had apoptotic activity toward target cells. Effect of the core protein on induction of FasL promoter was further examined by co-transfection of HepG2 cells with core-bearing plasmid and a vector in which luciferase gene expression is driven by human FasL promoter. Results of the luciferase assay indicated a positive regulation of FasL promoter by the core protein. In conclusion, HCV core protein plays a role in the induction of functional FasL in hepatoblastoma cell line and apoptosis in a target T cell line expressing Fas. Similar mechanisms may contribute, in vivo, to establishment of chronic infection and development of hepatocellular carcinoma (HCC).

Secretion and purification of HCV E1 protein forms as glutathione-S-transferase fusion in the baculovirus insect cell system.

We have expressed the E1 protein of Hepatitis C Virus (HCV) in a new recombinant form by using a baculovirus transfer vector directing the expression of proteins fused to the carboxy-terminus of glutathione-S-transferase (GST). The E1 domain was expressed varying at its carboxy terminus in order to retain (GST-E1) or delete (GST-E1b) the C-terminal hydrophobic region that may be involved in membrane association. Following infection with the recombinant virus, GST-E1b was efficiently secreted into the culture media and could be purified in a single step with the minimum of denaturation by glutathione affinity chromatography. The purified product was specifically immunoprecipitated by HCV positive human sera suggesting the maintenance of an immuno-relevant tertiary structure despite removal of the hydrophobic anchor. By contrast, cells infected with a recombinant baculovirus expressing GST-E1 gave a fusion protein with an appropriate molecular weight but also a series of polypeptides of lower molecular weight consistent with cleavage at the C-terminus of E1. GST-E1 was not secreted into the medium and was associated predominantly with the membrane fraction following cell disruption; the lower molecular weight forms were soluble and secreted.

The transmembrane domain of hepatitis C virus E1 glycoprotein induces cell death.

The E1 protein of hepatitis C virus (HCV) shows the ability to induce cell lysis by the alteration of membrane permeability when expressed in Escherichia coli cells. This function seems to be an intrinsic property of a C-terminal hydrophobic region of E1 as permeability changes and cell lysis can be blocked by mutagenesis of specific amino acids in this domain. To establish whether the expression of E1 protein and its C-terminal domain was able to induce cell death also in eukaryotic cell, we cloned HCV sequences expressing the full-length E1 (E383), the C-terminal domain (SVP) and a mutant lacking the C-terminal region (E340) in the pRC/CMV expression vector. HepG2 cell line was co-transfected with empty vector or HCV expression plasmids and a reporter vector that expressed beta-galactosidase (beta-gal) to visualize co-transfected blue cells. At 60 h after transfection, the loss of blue cells, considered as a measure of cell death, was 31.5 and 64.3% for the E1 and SVP clones. On the contrary, the number of blue cells after transfection with E340 plasmid was similar to that observed with the control vector. The analysis by the terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling (TUNEL) assay revealed an increased number of apoptotic cells at 48 h after transfection with E1 and SVP clones. Furthermore, cells transfected with SVP revealed a typical internucleosomal DNA fragmentation and the activation of caspase-3-like proteases as the specific inhibitor Ac-DEVD-CHO peptide partially blocked SVP apoptosis. These data indicate that the intracellular expression of HCV E1 protein and its C-terminal domain induces an apoptotic response in human hepatoma cell line.

High dosage alpha-interferon for treatment of children and young adults with chronic hepatitis C disease.

BACKGROUND: There are limited data on the use of high interferon (IFN) dosage for treatment of children and young adults with hepatitis C virus infection and in those affected by thalassemia major (TM). OBJECTIVES: To assess the response of children and young adults with chronic hepatitis C disease, including those affected by TM, to high dose natural alpha-interferon (IFN-alpha). To evaluate the effect of iron overload in response to high dose IFN-alpha in young chronic hepatitis C virus thalassemia patients. METHODS: We conducted a therapeutic trial of natural IFN-alpha, using 10 million units/m2 three times a week for 6 months in 14 chronic hepatitis C patients ages 5 to 28 years; 7 also had TM. The follow-up period lasted 12 months. RESULTS: Ten patients (73%) showed normal or nearly normal alanine aminotransferase values at the end of follow-up (biochemical response), but only five (35%) were negative for serum hepatitis C virus-RNA (complete responders). Four of the patients (57%) with TM were sustained complete responders. No correlation was found between the initial serum concentration of ferritin and response to IFN therapy. Patients infected with genotype 1b showed a poor response although high dose of natural IFN was used. CONCLUSIONS: These results indicate that IFN-alpha can be used in children and young patients with chronic hepatitis C disease as well as in those affected by TM. Treatment with high dosage natural IFN-alpha in children and young adults with hepatitis C infection does not appear to be more effective than dosages previously used.

Measles epidemiology in Italy.

In preparation for a mass vaccination programme, the immune status with regard to measles was determined in over 8300 unvaccinated children aged 0-13 years, residing in eight Italian cities with different socioeconomic situations and geographical locations. The age corresponding to the 50% prevalence of immunes appeared to be intermediate (2.9-5.5 years) between that reported for industrialized (6-7 years) and developing countries (1-2 years). The 50% prevalence of natural immunity was reached at an earlier age in southern cities in which poorer socioeconomic and hygienic conditions prevailed; the earlier occurrence of measles in these areas was confirmed by a more detailed serological study of children in the first 24 months of life. For children aged 2-13 years, serological results showed that the history of measles reported by parents on questionnaires gave high positive predictive values (over 85%). Our seroepidemiological study shows that, on the basis of the ages of 25 and 75% prevalence of immunes, the target population for a mass immunization programme in Italy can be assumed to be aged from 12 months to 7 years. However, special attention should be given to the poorest areas, especially in southern Italy, where measles occurs earlier and can be particularly severe.

Identification of scaffold/matrix attachment region in recurrent site of woodchuck hepatitis virus integration.

Scaffold or matrix attachment regions (S/MARs) are noncoding genomic DNA sequences displaying in vitro selective binding affinity for nuclear scaffold. They have been reported to be involved in the physical attachment of genomic DNA to the nuclear scaffold, and thus in the organization of the chromatin in functional loops or domains, and in the regulation of gene expression. In this work, we report the identification of an S/MAR in a woodchuck chromosomal locus, named b3n, previously described as a recurrent site of woodchuck hepatitis virus (WHV) DNA integration in woodchuck hepatocellular carcinoma (HCC). The 4.3-kb sequence of this locus contains several Alu-like repeats and a gag-like coding region with frameshift mutations. Computer analysis revealed the presence of a region with unusually high AT content, typical of most S/MARs, and of specific motifs (A boxes, T boxes, topoisomerase II sites, and unwinding elements) overlapping or in proximity to the region with high AT content, predicting that b3n might contain an S/MAR. Fragments of the b3n locus were isolated by conventional and inverse PCR techniques. In in vitro binding experiments with both heterologous and autologous scaffold preparations, a 592-bp fragment spanning the region rich in S/MAR features showed marked scaffold affinity, which was specific when autologous scaffolds were used. The presence of an S/MAR at the b3n locus and its nature as a recurrent WHV integration site in HCC suggest the involvement of S/MAR elements in some of the mechanisms leading to liver oncogenesis.

Chronic infection in woodchucks infected by a cloned hepatitis delta virus.

Two woodchucks (Marmota monax) intrahepatically inoculated with hepatitis delta virus (HDV) complementary DNA clones pSVL-D3 and pSVL-Ag showed virological and pathological signs of acute and chronic HDV infection. HDV-RNA and hepatitis delta antigen (HDAg) were detected in serum by slot-blot hybridization and by western blot five weeks after inoculation. Liver biopsy specimens collected at 8th week post inoculum were positive for HDV-RNA. Anti-HDV antibodies were detected at the 11th and 9th weeks, respectively. Histological finding of hepatocarcinoma and persistence of circulating HDV-RNA and anti-HDV were observed up to the 10th month. Both woodchucks produced "small" and "large" HDAg antigen, although the inoculated cloned DNA bears the coding capability solely for the small antigen. A transient decrease of woodchuck hepatitis virus DNA (WHV-DNA) level was observed during the peak of HDV infection. Successive inoculation of acute-phase serum in three woodchucks resulted in a successful infection in one of the animals.

A PCR-based strategy for rapid mapping of hepadnavirus integrated sequences in hepatocellular carcinomas.

A methodology based on polymerase chain reaction (PCR) and restriction analysis for rapid mapping of woodchuck hepatitis virus (WHV) integrations in hepatocellular carcinoma (HCC) tissues is described. Conventional PCR with viral primer pairs is not suitable for mapping WHV-integrated regions because the presence of minimum amounts of non-integrated (PCR amplifiable) WHV genome and replicative intermediates cannot be excluded. The first relevant part of the strategy is the identification of the cellular sequences flanking the WHV integration in order to select one (or more) integration-specific primer. The cellular flanking sequence can be rapidly obtained by means of inverse-PCR amplification of the viral/cellular junction and sequencing of the product. Mapping of the integrated regions is carried out by fixed flanking primer PCR (FFP-PCR) using the cellular primer as a 'fixed' primer in PCR association with each of an available set of WHV primers. Amplification of episomal WHV sequences is thus avoided. PCR products can also undergo restriction analysis. PCR-positive viral primers and specific WHV restriction sites are assembled into a map, based on the size and restriction pattern of the PCR products. The results of WHV integration mapping in a woodchuck HCC are described.

Experimental in ovo transmission of duck hepatitis B virus.

Inoculation of fertile Pekin duck eggs with diluted serum containing DHBV into eggs incubated for 24 h and into the extra-embryonic cavities of 14-day-old embryos resulted in a high proportion of viraemic ducklings irrespective of the route of inoculation. Long-term observation of som of the ducks established that the viraemia induced experimentally is long-lasting and has persisted for periods up to 16 mth post-hatch. Separation of DHBV from the plasma of carrier ducks by rate zonal centrifugation was examined by DNA polymerase (DNAP) activity. Particles in the fraction with peak DNAP activity had a buoyant density of 1.16 g X cm-3 in sucrose and an estimated sedimentation coefficient, S20.w of 77. DHBV particles, the morphology of which could be resolved under the electron microscope, consisted of a coat (about 10 nm in thickness) surrounding a core with a diameter measuring 40 nm but not 27 nm as previously reported. Spike-like projections were found on the surface of the core as described previously by W.S. Mason, G. Seal and J. Summers, 1980, J. Virol. 36, 829-836.

Antibody assay for measles virus: comparisons of immune-adherence haemagglutination, single radial haemolysis, enzyme immunoassay and haemagglutination inhibition.

Immune-adherence haemagglutination (IAHA); single radial haemolysis and enzyme immunoassay (ELISA) versus haemagglutination inhibition (HAI) for detecting antibodies to measles virus were evaluated. The rank correlation computed according to Spearman for the sera of healthy individuals gave values of 0.66, 0.73, 0.72, respectively, for HAI-IAHA, HAI-single radial haemolysis (SRH) and HAI-ELISA. High percentages of accordance were observed as regards sera from both healthy and vaccinated individuals. In the case of vaccinated individuals the discordance analysis showed significant differences between HAI and IAHA, HAI and SRH, SRH and ELISA. The discordances indicate higher sensitivity of HAI and ELISA for the detection of seroconversion.

Seroprevalence of hepatitis A virus and Helicobacter pylori infections in the general population of a developed European country (the San Marino study): evidence for similar pattern of spread.

OBJECTIVE: To evaluate the role of faecal-oral transmission in the spread of Helicobacter pylori. DESIGN: A cross-sectional comparison of the patterns of hepatitis A and H. pylori seropositivity. METHODS: At interview, blood samples and questionnaire data were collected from a random sample of 1528 healthy subjects aged 20-85 years from the Republic of San Marino. Serum samples from each subject were then tested for anti-H. pylori and anti-hepatitis A antibodies. RESULTS: Overall, 529 of 670 H. pylori-seropositive subjects (78.9%) and 460 of 858 H. pylori-seronegative subjects (53.6%) were hepatitis A seropositive (P<0.01; odds ratio=3.2; confidence interval 95%=2.6-4.1). This association remained after adjustment by a multiple logistic regression analysis for the confounding effect of age and length of schooling, as surrogate for socio-economic status (OR=2.0; CI 95%=1.3-3.3). The age-specific prevalence curves for H. pylori and hepatitis A infections showed a parallel increase by age, although to a lesser extent for H. pylori. CONCLUSION: These findings provide evidence that in the community studied H. pylori may have spread in a manner similar to that of hepatitis A.

Different levels of variability in subtypes 1b and 4a of hepatitis C viruses.

We performed genetic and phenic analyses to evaluate nucleotide and amino-acid sequences of the amino-terminus of the E1 protein of HCV genotype 1b (extracted from databank) and 4a (characterised in this study). The non-synonymous (ka) mutation analysis demonstrated that the genome of genotype 1b was not saturated by variations, with a rate of transition/transversion (s/v) of 1.5, which is similar to the expected ratio (i.e., 2.0). The s/v ratio in genotype 4a isolates was lower (0.98), indicating saturation due long-term variability. Moreover, the genotype 1b sequences showed a higher number of ka mutations (s+v) (mean of 2.8 per sequence) than genotype 4a (mean of 1.5). The introduction of ka mutations resulted in a higher degree of amino acid variability in genotype 4a. In the genome of genotype 1b, each nucleotide mutation introduced new amino acids, with a Granthan distance of 3.35-42.5, whereas for genotype 4a the distances ranged from 48.8 to 102.1. The phenic analysis also indicated different and complex patterns of amino-acid substitution. Finally, diverse isoelectric points and hydrophobicity were predicted for the two genotypes, with a higher acidity for genotype 4a E1 proteins.

Baseline sero-epidemiology of hepatitis B virus infection in children and teenagers in Italy. A survey before mass hepatitis B vaccination.

During the period May 1987 to November 1989, the prevalence of hepatitis B virus (HBV) markers was determined by ELISA in serum samples of 7405 (55% male, 45% female) apparently healthy persons 3-19 years of age in Italy. Earlier studies of adults there had shown an intermediate degree of HBV endemicity (hepatitis B surface antigen carrier rate greater than 2%). Persons were selected by systematic cluster sampling in five different geographical areas of Italy. The overall prevalence of hepatitis B surface antigen (HBsAg) was 0.6%. The overall prevalence of at least one marker of HBV was 2.8%; it increased from 1.7% among children 3-5 years of age to 4.5% in teenagers 17-19 years of age (P less than 0.001). The prevalence of any HBV marker was higher in southern then in northern areas (3.5% vs. 1.8%, P less than 0.001). A significant association was found with sociodemographic features. Persons whose fathers had less than 6 years of schooling had a 2.3-fold risk (C.I. 95% = 1.5-3.4) while those belonging to a household of six or more under one roof had a 1.7-fold risk (C.I. 95% = 1.2-2.4) of previous exposure to HBV infection. These findings indicate that, today in Italy, exposure to HBV infection at a young age is very low and suggest a shift towards a low degree of endemicity following improvements in socio-economic conditions, decreased family size and increasing use of disposable syringes during recent years.(ABSTRACT TRUNCATED AT 250 WORDS)