Epidemiologia da infecção pelo vírus da hepatite b em assentados em Goiás: subsídios para ações de prevenção e controle em populações emergentes

• Ano de defesa: 2014
• Autor(a) principal: Caetano, Karlla Antonieta Amorim
• Orientador(a): Teles, Sheila Araujo
• Banca de defesa: Teles, Sheila Araujo, Saddi, Vera Aparecida, Carneiro, Megmar Aparecida dos Santos, Junqueira, Ana Luíza Neto, Castro, Ana Rita Coimbra Motta de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Programa de Pós-graduação em Ciências da Saúde (FM)
• Departamento: Faculdade de Medicina - FM (RG)
• País: Brasil
• Palavras-chave em Português: Epidemiologia; Hepatite B; Vacinas contra hepatite B; População rural
• Palavras-chave em Inglês: Epidemiology; Hepatitis B; Hepatitis B vaccines; Rural population
• Área do conhecimento CNPq: CIENCIAS DA SAUDE
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tede/3551

Estimates indicate a total of 240 million chronic hepatitis B carriers worldwide. In Brazil, rural settlements present adverse life conditions that favor the acquisition of health problems, such as the hepatitis B virus (HBV). The objective of the present study was to investigate the epidemiology of the infections caused by the hepatitis B and D viruses in people living in settlements in the southwest region of the state of Goiás. This is an observational, analytical, cross-sectional study, with a subsequent cohort of susceptible subjects for vaccination against HBV, assessment of adherence and vaccine response. In the period from May to July of 2011, 467 subjects were selected from seven settlements in the southwest of Goiás. All subjects were interviewed and tested for the detection of the serological markers HBsAg, anti-HBc and anti-HBs, by means of the enzyme-linked immunosorbent assay (ELISA). Reactive HBsAg samples were tested for total anti-HDV and IgM, by means of the ELISA, submitted to the detection of the HBV DNA by semi-nested PCR and genotyped by sequencing. Chemiluminescent microparticle immunoassay was used for the quantitative determination of anti-HBs. The research proposal was approved by the Research Ethics Committee of the Federal University of Goiás. Of the total sample, 52.2% were men, 57.8% were married and 49% had less than five years of education. Most subjects were from cities in the midwest region (81.6%) and were older than 19 years of age (73.7%). Overall prevalence for infection by the HBV was 10.9% (51/467), being 0.8% (4/467) for HBsAg, 7.9% (37/467) for anti-HBc and anti- HBs, and 2.1% (10/467) for anti-HBc. Moreover, 19.3% of the people living in settlements presented isolated positivity for the anti-HBs marker, which indicates they were previously vaccinated against hepatitis B. The four reactive HBV DNA samples were classified as subgenotype A1 (3/4) and D3 (1/4). The male gender (adjusted OR: 2.65; p= 0.007), age (adjusted OR: 1.07; p= 0.000), history of transfusion (adjusted OR: 2.52; p= 0.025) and greater period of time living in the settlements (adjusted OR: 1.10; p= 0.026) were variables associated with the HBV. A total of 181 subjects susceptible to the infection started vaccine against hepatitis B, but only 106 (58.6%; 106/181) completed the vaccine scheme. Of these, it was possible to assess the vaccine response in 77 subjects, and 68.8% (53/77) presented protective titers of anti-HBs. Of those subjects living in the settlements who did not respond to the vaccine, a greater proportion was male, had more than 40 years and was smokers (p< 0.001). No subject presented positivity for the anti-HDV marker. The results of this study evidence the need for effective strategies to prevent hepatitis B in the studied settlements, emphasizing vaccine against hepatitis. In light of the low vaccine response against this infection in older subjects, more immunogenic schemes are suggested, so as to induce a protective vaccine response.