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1.
Epidemiol Infect ; 145(2): 401-412, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27780490

RESUMO

This analysis assessed the utility of the limiting antigen avidity assay (LAg). Samples of people who inject drugs (PWID) in Greece with documented duration of HIV-1 infection were tested by LAg. A LAg-normalized optical density (ODn) ⩽1·5 corresponds to a recency window period of 130 days. The proportion true recent (PTR) and proportion false recent (PFR) were estimated in 28 seroconverters and in 366 samples collected >6 months after HIV diagnosis, respectively. The association between LAg ODn and HIV RNA level was evaluated in 232 persons. The PTR was 85·7%. The PFR was 20·8% but fell to 5·9% in samples from treatment-naive individuals with long-standing infection (>1 year), and to 0 in samples with the circulating recombinant form CRF35 AD. A LAg-based algorithm with a PFR of 3·3% estimated a similar incidence trend to that calculated by analyses based on HIV-1 seroconversions. In recently infected persons indicated by LAg, the median log10 HIV RNA level was high (5·30, interquartile range 4·56-5·90). LAg can help identify highly infectious HIV(+) individuals as it accurately identifies recent infections and is correlated with the HIV RNA level. It can also produce reliable estimates of HIV-1 incidence.


Assuntos
Afinidade de Anticorpos , Erros de Diagnóstico , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , Técnicas Imunoenzimáticas/métodos , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Feminino , Grécia , Humanos , Masculino , RNA Viral/sangue , Carga Viral
2.
J Viral Hepat ; 19(3): 182-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22329372

RESUMO

Hepatitis C virus (HCV) infection is a major cause for chronic liver disease and hepatocellular carcinoma. The HCV-ARF/core+1 protein is an alternative product of HCV core-encoding sequence of unknown biological function. Highly purified HCV core and ARF/core+1 recombinant proteins from HCV genotype 1a and HCV-ARF/core+1 recombinant protein from HCV genotype 3a were expressed in Escherichia coli. Using an enzyme-linked immunosorbent assay, we assessed the prevalence of anti-ARF/core+1 antibodies in 90 chronic hepatitis C patients infected with HCV genotypes 1a/1b or 3a, treated with pegylated interferon (Peg-IFN-a-2a) plus ribavirin. Samples derived from 92 healthy blood donors were used as negative controls. All HCV-RNA-positive serum samples reacted with core 1a antigen, while 15 (37.5%) of 40 and 14 (28%) of 50 patients infected with HCV-1a/1b and HCV-3a, respectively, were found to have anti-ARF/core+1 antibodies into their serum before treatment initiation. These antibodies were persistently present during treatment follow-up and linked to elevated levels of HCV-RNA at baseline.


Assuntos
Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/imunologia , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Proteínas do Core Viral/imunologia , Adulto , Idoso , Antivirais/uso terapêutico , Quimioterapia Combinada , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Hepacivirus/imunologia , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico , Proteínas do Core Viral/genética , Adulto Jovem
3.
Epidemiol Infect ; 138(3): 403-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19698211

RESUMO

A cross-sectional study was carried out in injecting drug users (IDUs) from Greece to assess the seroprevalence of human herpesvirus 8 (HHV-8) and to identify potentially associated risk factors. A total of 288 IDUs were tested for K8.1 antibodies to HHV-8 lytic antigen. Associations between HHV-8 serostatus and potential risk factors were examined using univariate and multivariate logistic regression analysis. Seroprevalence of HHV-8 was 24.3% (95% CI 19.5-29.7), increasing with age from 19.4% in those aged <30 years to 52.9% in those aged 40 years (P for trend=0.003). No statistically significant associations between HHV-8-positive status and gender, educational level, age at first drug injection, needle sharing, number of imprisonments, complications from drug overdose, HIV and HCV were observed. In the multivariate logistic regression analysis, older age (40 vs. <40 years, OR 3.30, 95% CI 1.14-9.56) and report of septicaemia/abscess (yes vs. no, OR 1.80, 95% CI 1.01-3.18) were each independently associated with higher HHV-8 seroprevalence. HHV-8 is highly prevalent in the IDU population in Greece. The independent association between HHV-8 and reported abscess or septicaemia supports the hypothesis that poor hygiene conditions in the setting of drug injection may contribute to HHV-8 transmission.


Assuntos
Infecções por Herpesviridae/sangue , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/isolamento & purificação , Estudos Soroepidemiológicos , Abuso de Substâncias por Via Intravenosa , Adolescente , Adulto , Anticorpos Antivirais/sangue , Estudos Transversais , Feminino , Grécia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
4.
J Viral Hepat ; 12(5): 543-50, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16108772

RESUMO

SUMMARY: The epidemic of hepatitis C virus (HCV) infection is a major public health issue. We conducted a comprehensive analysis to estimate future HCV-related morbidity and mortality, using a model which is the first to take into account currently available treatments. We reconstructed the incident infections per year in the past that progressed to chronic hepatitis C (CHC) in Greece. Then, the natural history of the disease was simulated in subcohorts of newly infected subjects in the presence or absence of treatment using yearly estimates of the number of treated patients obtained from national databases. Annual estimates of the incidence and prevalence of CHC by fibrosis stage, hepatocellular carcinoma (HCC) and mortality were obtained up to 2030. The current proportion of naïve CHC patients receiving treatment in Greece is 1.2% per year. Treatment of 1.2-10% of naïve CHC patients per year would reduce the cumulative number of incident cirrhosis and HCC cases from 2002 to 2030 by 10.8-39.4% and 12.8-39.8%, respectively and decrease the number of prevalent cirrhosis and HCC cases in 2030 by approximately 17-48% compared with the number estimated under the assumption of no treatment. Approximately 17 cirrhosis cases or six HCC cases or 10 premature deaths would be prevented for every 100 treated patients. However, the prevalent cirrhotic/HCC cases because of HCV and HCV-related deaths would not plateau until 2030. Despite the introduction of effective treatment, HCV-related morbidity and mortality will likely increase during the next 20-30 years in Greece. Intensive primary prevention efforts coupled with increased access to the currently available treatments are necessary to control the chronic consequences of HCV epidemic.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/complicações , Cirrose Hepática/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/virologia , Progressão da Doença , Previsões , Grécia/epidemiologia , Hepatite C Crônica/transmissão , Humanos , Incidência , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Falência Hepática/epidemiologia , Falência Hepática/etiologia , Modelos Estatísticos , Prevalência , Probabilidade
5.
J Viral Hepat ; 11(4): 366-74, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15230860

RESUMO

In this study, a comprehensive methodology for modelling the hepatitis C virus (HCV) epidemic is proposed to predict the future disease burden and assess whether the recent decline in the incidence of HCV may affect the future occurrence of cirrhosis and hepatocellular carcinoma (HCC) cases. Using the prevalence of HCV, the distribution of chronic hepatitis C (CHC) patients within the various transmission groups and their infection-onset times, it was possible to reconstruct the incident infections per year in the past that progressed to CHC in Greece. The natural history of the disease was simulated in subcohorts of newly infected subjects using transition probabilities derived either empirically between fibrosis stages 0-4 or from literature review. Annual estimates of the incidence and prevalence of CHC by fibrosis stage, HCC and mortality in Greece were obtained up to 2030. HCV incidence peaked in the late 1980s at five new infections/10,000 person-years. Under the assumption of 20-100% decline in HCV incidence after 1990, the cumulative number of incident cirrhosis and HCC cases from 2002-2030 was projected to be lower by 9.6-48.2% and 5.9-29.5%, respectively, than that estimated under the assumption of no decline. However, the prevalent cirrhotic/HCC cases and HCV-related deaths are predicted to decline in the next 30 years only under the assumption of complete elimination of new HCV infections after 1990. Despite the progress in the reduction of HCV transmission, primary prevention does not seem adequate to reverse the rise in the incidence of cirrhosis and HCC.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/epidemiologia , Cirrose Hepática/epidemiologia , Modelos Estatísticos , Carcinoma Hepatocelular/virologia , Progressão da Doença , Previsões , Grécia/epidemiologia , Hepatite C Crônica/transmissão , Humanos , Incidência , Cirrose Hepática/virologia , Falência Hepática/epidemiologia , Falência Hepática/etiologia , Prevalência , Probabilidade
6.
Eur J Epidemiol ; 17(8): 721-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12086089

RESUMO

A cross-sectional study was carried out in employees of 17 Greek companies with the aim of assessing the prevalence of hepatitis B (HBV) and hepatitis C (HCV) virus, identifying associated prognostic/risk factors and evaluating the effectiveness of a questionnaire as a pre-screening tool. All participants were asked to complete a questionnaire and a random sample of them was asked to provide a blood sample for hepatitis B core antibody (anti-HBc), hepatitis B surface antigen (HBsAg) and antibodies to hepatitis C (anti-HCV) testing. Individual questions or combinations of them were evaluated in terms of their ability to detect HBV or HCV(+) cases. Of 9085 eligible employees, 6074 (67%) completed the questionnaire. Of 990 samples obtained, 19.9% were anti-HBc(+), 2.6% HBsAg(+) and 0.5% anti-HCV(+). All anti-HCV(+) cases had multiple parenteral risk factors. Multiple logistic regression identified associations between anti-HBc and older age, family members with chronic hepatitis, job category and history of transfusion before 1992. HBsAg(+) was associated with older age and history of transfusion before 1992. None of the risk/prognostic factors had sufficient sensitivity and specificity for HBV but report of at least one risk factor identified all HCV(+) cases. Anti-HCV screening of those with at least two parenteral risk factors not only identified all anti-HCV(+) cases but also resulted in 86% decrease in the screening cost. Under the light of recent treatment advances, targeted questionnaire-based screening of asymptomatic people may prove to be a cost-effective way to face hepatitis C.


Assuntos
Hepatite B/diagnóstico , Hepatite C/diagnóstico , Serviços de Saúde do Trabalhador/organização & administração , Adolescente , Adulto , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Grécia/epidemiologia , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Técnicas Imunoenzimáticas , Modelos Logísticos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Prognóstico , Avaliação de Programas e Projetos de Saúde , Fatores de Risco , Sensibilidade e Especificidade , Inquéritos e Questionários
7.
J Med Virol ; 61(3): 319-26, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10861639

RESUMO

The relevance of GB virus C/hepatitis G virus (GBV-C/HGV) infections in liver pathology remains unclear. To investigate the epidemiology of GBV-C/HGV in Athens, Greece, sera from 512 subjects were screened for present and past markers of GBV-C/HGV infection using a reverse transcription-polymerase chain reaction (RT-PCR) and a serological assay, respectively. GBV-C/HGV RNA was detected in 18/56 (32.1%), 12/42 (28.6%), and 16/55 (29.1%) patients with acute hepatitis B, C, or non-A-E, and in 5/58 (8.6%) and 18/68 (26.5%) patients with chronic hepatitis B or C, respectively, as well as in 50/133 (37.6%) hemodialysis patients and 10/100 (10%) healthy individuals. The data indicated that GBV-C/HGV seroprevalence is age-dependent; thus, GBV-C/HGV RNA and anti-E2 positivity were shown to be associated with younger age [odds ratio 0.98, 95% confidence interval (CI) 0. 97-1.00, P = 0.017] and older age (odds ratio 1.03, 95% CI 1.01-1.05, P = 0.002), respectively. No significant associations were identified between GBV-C/HGV RNA status and alanine aminotransferase (ALT) levels in either hepatitis or hemodialysis patients. Nevertheless, GBV-C/HGV RNA-positive acute non-A-E hepatitis patients were more likely to manifest a more severe clinical form of acute hepatitis (P = 0.024). Phylogenetic analysis of partial 5'-untranslated region sequences isolated from 18 viremic individuals showed that most GBV-C/HGV strains circulating in the greater metropolitan area of Athens belong to the 2a subgroup. A genetically diverse type 2 sequence that may represent a novel subtype within group 2 was also characterized.


Assuntos
Flaviviridae/genética , Hepatite Viral Humana/epidemiologia , Epidemiologia Molecular , Regiões 5' não Traduzidas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Criança , Feminino , Flaviviridae/imunologia , Flaviviridae/isolamento & purificação , Grécia/epidemiologia , Anticorpos Anti-Hepatite/sangue , Hepatite Viral Humana/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Viral/sangue , Análise de Sequência de DNA , Proteínas do Envelope Viral/imunologia
8.
J Hepatol ; 27(1): 36-41, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9252071

RESUMO

AIM: To investigate the significance of IgM antibody to hepatitis C virus (HCV) core antigen (IgM anti-HCV core) in chronic hepatitis C. METHODS: In a group of 112 patients with histologically proven chronic hepatitis C positive for HCV RNA, IgM anti-HCV core level was studied by a sensitive semi-quantitative enzyme immunoassay. Quantitation of serum HCV RNA was done by a second generation bDNA assay and determination of HCV genotype by RT-PCR and reverse hybridization. RESULTS: IgM anti-HCV core was detected in 72 (64.3%) of the 112 patients. ALT levels were significantly higher in IgM anti-HCV core positive than negative patients. No other significant difference was observed in any of the patients' characteristics between IgM anti-HCV core positive and negative groups. On the contrary, IgM anti-HCV core level was found to be significantly higher in females than in males, in patients with moderate or severe chronic hepatitis, in patients with high HCV RNA levels and in patients infected with HCV genotype 1b. Moreover, IgM anti-HCV core level was significantly correlated with age and ALT level. Multiple regression analysis showed that IgM anti-HCV core level was significantly related only to the HCV genotype (p=0.001), histological grade (p=0.017) and ALT level (p=0.038). CONCLUSIONS: Our data support the hypothesis that IgM anti-HCV core level is associated mainly with HCV genotype and secondly with liver disease necroinflammatory activity. These associations may have implications in the pathogenesis of chronic hepatitis C.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Antígenos da Hepatite C/imunologia , Hepatite C/imunologia , Imunoglobulina M/sangue , Proteínas do Core Viral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/patologia , Hepatite C/virologia , Humanos , Imunoglobulina M/imunologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Índice de Gravidade de Doença , Fatores Sexuais
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