HCV genotype 6 is restricted in its distribution in South East Asia and it has been circulating for a long period of time. Phylogenetic and phylodynamic analysis on epidemic history of HCV focusing genotype 6 in South East Asia was explored, taking references from the pattern delineated in Liuzhou. Our results show that the date of most recent common ancestor (MRCA) of the whole HCV genotype 6 was estimated to be 100 years ago or more. There was an obvious increase of effective number of HCV genotype 6 infections in the part 20 years. Epidemic history of Subtype 6a and 6e/6d also showed the similar time course as that of the genotype 6. Interestingly, there was an increase of effective number of infections around 15-20 years ago which was maintained in the following decade for subtype 6a as well as 6e/6d. This specific pattern was consistent with the history of needle sharing in South East Asia, where the number of IDUs increased in the 1980s. The epidemic then spread to Southern China as evident by the increasing trend in Liuzhou. There was an exponential growth around 5 years ago involving subtype 6a predominantly, which might remain prevalent in Southern China in the coming decades. In conclusion, the study has shed new light on the transmission history of HCV, providing an explanation on the emergence of HCV genotype 6 in South East Asia. / HCV infection is an important public health problem associated with blood transfusion and needle-sharing in injection drug users (IDU) in Southern China. An understanding of the epidemiological pattern of the HCV infection, in conjunction with the transmission dynamics, would be beneficial for supporting effective prevention and control. This is accessed using a combination of molecular and public health approaches. / Through the Liuzhou Methadone Clinic, a total of 117 IDUs were recruited from Guangxi, Southern China. A majority of the IDUs (96%) were HCV antibody positive, of which 21% were HIV infected. Unlike HCV monoinfection, there was spatial heterogeneity in the distribution of HIV/HCV coinfection. The latter was also characterised by a higher prevalence of needle-sharing. Phylogenetic analysis of HCV revealed that genotype 6a was predominant in the study population. There were shorter genetic distances among the 6a samples compared to 3 other HCV genotypes/subtypes, 1a, 3a, and 3b. Our results suggested that HIV and HCV were both introduced at around the same time to the IDU populations in Southern China, followed by their differential spread as determined by the biologie characteristics of the virus and the intensity of behavioural risk. This pattern might be different from that in other South East Asian countries where HCV infections have probably predated HIV. / Tan, Yi. / Adviser: Kung Hsiang-fu. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3404. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 164-178). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Pacientes em hemodiálise possuem um risco elevado de adquirir o vírus da hepatite C(VHC) e a transmissão nosocomial continua contribuindo para o aparecimento de novos casos. Este estudo analisa o seguimento de novos casos de hepatite aguda C, de janeiro de 2002 a maio de 2005,em um centro de Hemodiálise, no Sudoeste do Paraná,Brasil e da eficácia das medidas implantadas para conter a ocorrência de novos casos.Durante o período 32 novos casos foram identificados. Os testes de anti-VHC e transaminases realizados mensalmente mostraram níveis variáveis de ALT precedendo a soroconversão anti-VHC. A viremia, dada pelo RNA VHC, foi intermitente e eventualmente negativa.Toda a equipe foi re-treinada para seguir rigorosamente as Recomendações para Prevenção de Transmissão de Infecções entre os pacientes em Hemodiálise, e o último caso diagnosticado foi em Maio de 2004 / Chronic hemodialysis patients are at higher risk for acquiring the hepatitis C virus (HCV) and the nosocomial transmission still accounts for the new cases.This study analyzed the follow up of newly acquired acute hepatitis C cases, from January 2002 to May 2005, in the Hemodialysis Center, Southwest region of Parana State, Brazil and analyzed the effectiveness of the measures to restrain the occurrence of new cases. During this period 32 new cases were identified. Anti-HCV and ALT monthly tests showed variable ALT levels preceding the anti-HCV seroconversion. The HCV RNA viremia was intermittently and even negative in some cases. All staff was re-trained to strictly follow the Recommendations for Preventing Transmission of Infections among Chronic Hemodialysis Patients and the last case was diagnosed in May 2004

Pacientes em hemodiálise possuem um risco elevado de adquirir o vírus da hepatite C(VHC) e a transmissão nosocomial continua contribuindo para o aparecimento de novos casos. Este estudo analisa o seguimento de novos casos de hepatite aguda C, de janeiro de 2002 a maio de 2005,em um centro de Hemodiálise, no Sudoeste do Paraná,Brasil e da eficácia das medidas implantadas para conter a ocorrência de novos casos.Durante o período 32 novos casos foram identificados. Os testes de anti-VHC e transaminases realizados mensalmente mostraram níveis variáveis de ALT precedendo a soroconversão anti-VHC. A viremia, dada pelo RNA VHC, foi intermitente e eventualmente negativa.Toda a equipe foi re-treinada para seguir rigorosamente as Recomendações para Prevenção de Transmissão de Infecções entre os pacientes em Hemodiálise, e o último caso diagnosticado foi em Maio de 2004 / Chronic hemodialysis patients are at higher risk for acquiring the hepatitis C virus (HCV) and the nosocomial transmission still accounts for the new cases.This study analyzed the follow up of newly acquired acute hepatitis C cases, from January 2002 to May 2005, in the Hemodialysis Center, Southwest region of Parana State, Brazil and analyzed the effectiveness of the measures to restrain the occurrence of new cases. During this period 32 new cases were identified. Anti-HCV and ALT monthly tests showed variable ALT levels preceding the anti-HCV seroconversion. The HCV RNA viremia was intermittently and even negative in some cases. All staff was re-trained to strictly follow the Recommendations for Preventing Transmission of Infections among Chronic Hemodialysis Patients and the last case was diagnosed in May 2004

Made available in DSpace on 2015-04-11T13:55:00Z (GMT). No. of bitstreams: 1 midia barbosa.pdf: 2406682 bytes, checksum: 16c04c78a5dd5af5cfe75dbf61b6b5e6 (MD5) Previous issue date: 2013-08-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Hepatitis C is a disease characterized by the inflammation of the liver with HCV transmitted primarily through infected blood. It is estimated that 170 million people, about 3% of the world population, is infected with hepatitis C. Unlike other viruses that cause hepatitis, HCV does not generate adequate immune response in the body, which makes 80% of the infected to evolve into chronicity, whereas 15 to 20% of infected people heal spontaneously. In Brazil there is a significant variation in the prevalence of infection, the main cause of this epidemiological distinction is the characteristics differences between populations and geographic that each region studied has, and the limited epidemiological data about the disease. There is no vaccine against hepatitis C virus, thus early diagnosis increases the effectiveness of treatment. The aim of this study was to characterize the epidemiological, virological and immunological anti-HCV general population living in the city of Iranduba, metropolitan region of Manaus. Where were evaluated 700 volunteers and it was detected a positive case, using a rapid anti-HCV test, despite the presence of classical risk factors for infection in the seronegative volunteers. The realization of a molecular test, the polymerase chain reaction, confirmed the diagnosis of infection and by phylogenetic analysis of the NS5B region of the viral genome was observed genotype 2b. Among cytokines quantified, in the anti-HCV positive case, IL-2, IL-6, IL-10, TNF-α and IL-17A were more prevalent. The study showed serumprevalence anti-HCV of 0.14%, ranking the city as a place of low endemicity for HCV and reinforcing the heterogeneous characterization of the Amazon of hepatitis C. / A hepatite C é uma doença caracterizada pela inflamação do fígado, sendo o vírus HCV transmitido, principalmente, através de sangue contaminado. Estima-se que 170 milhões de pessoas, cerca de 3% da população mundial, sejam portadores de hepatite C. Ao contrário dos demais vírus que causam hepatite, o HCV não gera resposta imunológica adequada no organismo, o que faz com que 15 a 20% das pessoas infectadas curem espontâneamente, enquanto 80% evoluem para cronificação da doença. No Brasil ocorre grande variação na prevalência da infecção, isso se deve principalmente, as distintas características epidemiológicas entre as populações e a região geográfica estudada, além de restritas informações sobre a doença. Não existe vacina contra a hepatite C, assim o diagnóstico precoce amplia a eficácia do tratamento. O objetivo deste trabalho consistiu em caracterizar o perfil epidemiológico, virológico e imunológico anti-HCV na população geral, residente no município de Iranduba, região metropolitana de Manaus. Participaram da pesquisa 700 voluntários. Foi detectado um caso positivo no teste rápido anti-HCV, apesar da presença dos clássicos fatores de risco para a infecção nos voluntários soronegativos. A realização do teste molecular, reação em cadeia da polimerase, confirmou o diagnóstico da infecção e através da análise filogenética da região NS5B do genoma viral foi constatado o genótipo 2b. Dentres as citocinas quantificadas, no caso anti-HCV positivo, IL-2, IL-6, IL-10, TNF-α e IL-17A foram mais prevalentes. O estudo apontou soroprevalência anti-HCV de 0,14%, classificando o município de Iranduba como local de baixa endemicidade para o HCV e reforçando a caracterização heterogênea do Amazonas para a hepatite C.