Prevalence of hepatitis A virus infection: the paradoxical example of isolated communities in the western Brazilian Amazon region

• Autor(a) principal: Braga,Wornei Silva Miranda
• Data de Publicação: 2009
• Outros Autores: Borges,Fabiane Giovanella, Barros Júnior,Gildo Maia, Martinho,Ana Cristina de Souza, Rodrigues,Ivo Seixas, Azevedo,Eliete Pereira de, Davis,Gustavo Henrique Nolasco Grimmer, Queiroz,Manoel Bezerra de, Santos,Simone Helena Derzi dos, Barbosa,Thiago Vitoriano, Castilho,Márcia da Costa
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista da Sociedade Brasileira de Medicina Tropical
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0037-86822009000300008
• topic: Hepatitis A virus; Epidemiology; Prevalence; Amazon region; Brazil

This study evaluated the prevalence of hepatitis A virus infection in the rural area of Lábrea, in the western Brazilian Amazon region. Communities and households were selected randomly. Serum samples were analyzed by means of the immunoenzymatic method for the presence of total antibodies against HAV. The study included 1,499 individuals. The prevalence of anti-HAV was 74.6% (95% CI 72.3-76.8). Univariate analysis showed associations with age (chi-square for linear trend = 496.003, p < 0.001), presence of outside toilet (p < 0.001), history of hepatitis (p < 0.001) and family history of hepatitis (p = 0.05). After adjusting for age, HAV infection also showed an association with the number of people in the family (p = 0.03). The overall prevalence rates were high, but not more than 60% of the children under the age of ten years had already been infected. Very high prevalence was detected only within older cohorts, thus paradoxically defining this as a region with intermediate endemicity, even under the conditions of poverty encountered.