The impact of hepatitis B virus (HBV) genotypes on the sensitivity of surface antigen (HBsAg) detection assays has been poorly investigated. Here, plasmids carrying consensus or variant coding sequences for HBV surface proteins from genotypes A, D and F, were constructed. HBsAg levels were evaluated in medium and extracts of transfected CHO cells by a commercial polyclonal-based assay. We show that HBsAg detection values of consensus forms from genotypes D and F were, respectively, 37% and 30% lower than those obtained by genotype A. However, the presence of two single variations, T143M in genotype A, and T125M in genotype D, produced a decrease of 44% and an increase of 34%, respectively, on HBsAg mean values in comparison with their consensus forms. In conclusion, HBsAg detection levels varied among HBV genotypes. However, unique amino acid substitutions not linked to genotypes, such as T125M and T143M described here, should have more implications in HBV immunological diagnostics than the set of variations characteristic of each HBV genotype.

A adesão e resposta à vacina contra hepatite B foram avaliadas em comunidades remanescentes de quilombos no Brasil Central. Um total de 708 indivíduos suscetíveis à infecção pelo vírus da hepatite B foi convidado para participar do programa de vacinação contra hepatite B em oito comunidades. Apesar de 567 (80%) indivíduos terem recebido a primeira dose, somente 198 (28%) aderiram ao esquema completo de vacinação. De 148 sujeitos que concordaram em dosar o anti-HBs, 123 (83,1%; IC95%: 75,9-88,6) responderam à vacina. Um título geométrico médio de 512mUI/mL (IC95%: 342,5-765,3) foi encontrado. Sexo masculino e idade foram independentemente associados com ausência de resposta. Programas adicionais de educação em saúde e esquemas alternativos de vacinação contra hepatite B são necessários para melhorar a cobertura vacinal nessas comunidades no Brasil Central.

Compliance with and responses to the hepatitis B vaccine were evaluated in remaining quilombo communities in Central Brazil. A total of 708 individuals who were susceptible to hepatitis B virus infection were invited to participate in the hepatitis B vaccination program in eight communities. Although 567 (80%) individuals received the first dose, only 198 (28%) complied with the full vaccination scheme. Of 148 subjects who agreed to be tested for anti-HBs, 123 (83.1%; 95%CI: 75.9-88.6) responded to the vaccine. A geometric mean titer of 512mIU/mL (95%CI: 342.5-765.3) was found. Male sex and older age were independently associated with non-response. Additional health education programs and alternative hepatitis B vaccine schedules are needed to improve the vaccination coverage in these communities in Central Brazil.

A adesão e resposta à vacina contra hepatite B foram avaliadas em comunidades remanescentes de quilombos no Brasil Central. Um total de 708 indivíduos suscetíveis à infecção pelo vírus da hepatite B foi convidado para participar do programa de vacinação contra hepatite B em oito comunidades. Apesar de 567 (80%) indivíduos terem recebido a primeira dose, somente 198 (28%) aderiram ao esquema completo de vacinação. De 148 sujeitos que concordaram em dosar o anti-HBs, 123 (83,1%; IC95%: 75,9-88,6) responderam à vacina. Um título geométrico médio de 512mUI/mL (IC95%: 342,5-765,3) foi encontrado. Sexo masculino e idade foram independentemente associados com ausência de resposta. Programas adicionais de educação em saúde e esquemas alternativos de vacinação contra hepatite B são necessários para melhorar a cobertura vacinal nessas comunidades no Brasil Central.

Compliance with and responses to the hepatitis B vaccine were evaluated in remaining quilombo communities in Central Brazil. A total of 708 individuals who were susceptible to hepatitis B virus infection were invited to participate in the hepatitis B vaccination program in eight communities. Although 567 (80%) individuals received the first dose, only 198 (28%) complied with the full vaccination scheme. Of 148 subjects who agreed to be tested for anti-HBs, 123 (83.1%; 95%CI: 75.9-88.6) responded to the vaccine. A geometric mean titer of 512mIU/mL (95%CI: 342.5-765.3) was found. Male sex and older age were independently associated with non-response. Additional health education programs and alternative hepatitis B vaccine schedules are needed to improve the vaccination coverage in these communities in Central Brazil.