Molecular epidemiology of chronic hepatitis B virus infection in northern Poland
Department of Biotechnology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kladki 24, 80-822 Gdansk, Poland. Journal of Clinical Virology
(Impact Factor: 3.02).
01/2006; 34 Suppl 1(Suppl 1):S63-9. DOI: 10.1016/S1386-6532(05)80012-5
Hepatitis B virus (HBV) infection is a global health problem, with more than 350 million people chronically infected worldwide. The chronic HBV infection in Poland is also an essential medical and social problem. Starting from 1993, a steady decline of the incidence of HBV has been observed, reaching the estimated rate of 4.5 per 100 000 in 2004. Nothing is known about the genetic variability of HBV in Poland, the occurrence and spreading of genetic variants and mutants of hepatitis B virus in the population of Polish patients during the course of the disease and in relation to antiviral treatment. It is very interesting to study the molecular epidemiology of the Polish population regarding hepatitis B virus infection as Poland is still ethnically a uniform country, with no more than 3-4% of ethnic minorities. The first results regarding distribution of HBV genotypes and serotypes in northern Poland have been published by our group in 2003 and 2004. This work was part of a scientific project supported by the Fifth Framework Programme initiative of the European Union, entitled "Emerging variants of hepatitis B virus: new tools for epidemiological survey, diagnosis of infection, and monitoring of drug resistance". In the course of the project more than 200 hepatitis B infected patients from the northern part of Poland have been enrolled, diagnosed and - if the viral load of HBV was suitable for analysis - genotyped by sequencing of the HBV pol/S gene fragment. This review presents the main characteristics and some interesting aspects of the studied cohort of chronically infected patients from northern Poland as well as the molecular epidemiology.
Available from: Vladimir Chulanov
- ", 2005 ] . In contrast , other central European countries such as Poland and the Czech Republic are still quite uniform ethnically , for example , the proportion of immigrants does not exceed 3 – 4% [ Bielawski and Stalke , 2005 ] . These data indicate that the emerging epidemiology of HBV infection in Central and Eastern Europe is not due to immigration of HBsAg - positive persons from high endemic Asian countries . "
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ABSTRACT: The importance of hepatitis B virus (HBV) genotypes for disease progression and response to interferon-alpha-based treatment is well established. While almost all patients in the Mediterranean area are infected with HBV genotype D, HBV genotype A is dominant in Northern Europe. However, the distribution of HBV genotypes is unknown for several Central and Eastern European countries. Data are described of 1313 HBsAg-positive patients recruited at 14 referral centers in eight countries. There were only very few cases of HBV genotype B, C, E, F, and H infection while HBV genotypes A and D were found in 42% and 48% of patients, respectively. Eight percent of patients had positive bands for more than one genotype using the hybridization assay. The frequency of genotype A was higher in Poland (77%) and the Czech Republic (67%) as compared to Hungary (47%), Lithuania (41%), Croatia (8%), and Germany (32%). In contrast, HBV genotype D was most frequent in Croatian, Romanian, and Russian patients with 80%, 67%, and 93% of cases, respectively. In conclusion, HBV genotype A versus D showed significantly different distribution patterns in Central and Eastern Europe which deserves consideration for national guidelines and treatment decisions. J. Med. Virol. 80:1707–1711, 2008. © 2008 Wiley-Liss, Inc.
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ABSTRACT: Nucleic acid testing (NAT) for hepatitis B virus (HBV) has been performed in Poland since 2005 on samples seronegative for hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (anti-HCV), and anti-human immunodeficiency virus (anti-HIV). Tools included 24-donation pool testing (PT) using Cobas Amplicor or in individual donations (ID) by Procleix Ultrio. Seven of 761,666 (1:108,800) and 21/250,191 (1:11,900) HBV DNA-positive donations were identified and confirmed by alternative methods. HBV DNA load ranged between 11.6 and 4.6 x 10(4) IU/mL in 11 samples and could not be quantified in 17 samples. HBV genotypes A (56%) and D (4%) were found. The analysis of combined results from index, follow-up, and look-back samples identified four groups: (1) Two cases tested HBsAg positive with alternative, more sensitive, assays; (2) Four cases were in the pre-seroconversion window period; (3) Eight cases had a fluctuating pattern of HBV DNA and anti-HBs detection (recovered infection); and (4) twelve cases carried anti-HBc without anti-HBs, which might correspond to either chronic or recovered "occult" HBV infection. One donor with no HBV markers in the follow-up was excluded, and another was in the window period preceding anti-HBs. HBV NAT identified more confirmed positive donors than HCV or HIV NAT, and 1:250,000 could not be detected by anti-HBc screening. Serological and molecular studies on follow-up and look-back samples are important to classify donors. In conclusion, further studies are needed to determine whether the considerably higher yield of HBV DNA detection obtained with individual donation screening improves blood safety compared with anti-HBc screening.
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ABSTRACT: A DGGE-based assay for hepatitis B virus (HBV) drug-resistance monitoring was designed and checked for feasibility. It detects mutations within the YMDD motif related to lamivudine resistance.
The YMDD motif of HBV polymerase was amplified by the set of primers designed in this study. DGGE analysis of the amplicons was performed on 9% polyacrylamide gels containing a 20-40% gradient of urea plus formamide and electrophoresis was performed. DNA sequencing was performed using a standard protocol.
Based on the DGGE pattern of previously sequenced HBV variants, a reference ladder consisting of bands was constructed within and near the YMDD motif of HBV with excellent resolution. The genotypes of all the fragments included in the ladder were confirmed by sequencing after DGGE analysis. The flexibility of DGGE was demonstrated by the ability to add more bands to the migration ladder when new variants were discovered during the analysis of patient specimens. Clinical samples from HBV-infected patients were also used to demonstrate the performance of this approach.
This preliminary feasibility study of HBV drug-resistance monitoring by means of DGGE shows the potential advantage of this approach for low-cost screening for viral drug resistance in clinical settings. The presented example can be extended to detect other mutations related to drug resistance in the HBV genome as well as other viruses.
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