The goal of this study was to investigate the prevalence of occult HBV infection in a reference center for the Northern Brazil from 2005 to 2015 and to identify mutations associated with occult hepatitis B. Molecular analysis was performed on 110 serum samples in which anti-HBc was the only positive serological marker. Regions of the HBV genome were amplified by polymerase chain reaction to detect HBV DNA. A prevalence of 4.1% (793/18,889) for anti-HBc alone was identified. Molecular analysis revealed a prevalence of occult HBV infection of 0.04%. HBV DNA detected were identified in individuals who underwent hemodialysis, infected with the hepatitis C virus and from area of high endemicity for HBV. Direct DNA nucleotide sequencing and phylogenetic analysis identified that genotypes A and D and mutations E164D, I195M, P217L and P120S were associated with occult HBV infection in the S gene. This study contributed with epidemiological and molecular information on Northern Brazil samples with a suggestive profile of occult HBV infection in addition to reinforcing the importance of molecular diagnosis in this type of infection.

O projeto buscou identificar por meio de estudo soroepidemiológico a prevalência da infecção pelos vírus das hepatites B e C e a situação imunológica para o vírus da hepatite B, em população afrodescendente das comunidades Santo Estevão, São Rosário e Sítio Itaussu, de município da Amazônia oriental brasileira, Pará, Brasil. Estudo descritivo, de corte transversal realizado entre 2020 e 2022 que avaliou amostras de soro e dados epidemiológicos de afrodescendentes, obtidas em projeto anteriormente desenvolvido nessas comunidades sobre as hepatites A e E, armazenadas no biorrepositório de instituto de pesquisa da Amazônia. Foram testados os marcadores HBsAg, anti-HBc total, anti-HBs e anti-VHC, por técnica de eletroquimioluminescência. Entre as 318 amostras analisadas, 50,9% eram mulheres, a média de idade era de 25,3±18,9 anos (variação de 8 meses a 97 anos) e mediana de 20 anos, e a maior frequência (53,8%) estava na Comunidade São Rosário. Não foram detectados resultados reagentes para o HBsAg significando ausência de portadores do VHB; 0,6% eram anti-HBc/anti-HBs reagentes, indicando infecção pregressa pelo VHB; 0,6% anti-HBc reagente isolado, expressando infecção recente ou pregressa pelo vírus; 26,7% anti-HBs reagente isolado, indicando imunidade obtida por vacina, estando suscetíveis ao VHB 72% das amostras avaliadas. Não foram encontrados resultados anti-VHC reagentes. A ausência de casos ativos das hepatites B e C indicou baixa prevalência desses agravos, entretanto mostrou a baixa imunidade produzida pela infecção e pela vacinação contra o VHB nessa população, traduzida pelo elevado número de suscetíveis ao vírus. O estudo contribuiu no suporte às autoridades de saúde do município do Acará em sua programação de promoção e prevenção à saúde para redução do número de suscetíveis e da transmissão dessas infecções nessa população quilombola.

The genus Bartonella comprises gram-negative bacilli that possess tropism for erythrocytes and endothelial cells in animals of the orders Rodentia, Lagomorpha, Carnivora, Artiodactyla, Eulipotyphla, and Chiroptera. Bacterial infection may be associated with lymphadenitis, endocarditis, bacillary angiomatosis, and peliosis hepatis. Thirteen species of Bartonella are recognized as zoonotic and bats are considered to be their potential reservoirs. This study aimed to analyze the occurrence of Bartonella spp. in livers of neotropical bats belonging to the families Molossidae, Phyllostomidae, and Vespertilionidae, classified into 21 genera from the Atlantic Forest biome in São Paulo. A total of 341 (n = 341) chiropterans samples were tested for the presence of citrate synthase (gltA) gene of Bartonella by partial amplification using polymerase chain reaction (PCR). Samples of two bats (0.6%) of the species Glossophaga soricina from the municipality of São Roque were tested positive for gltA gene. Phylogenetic analysis indicated that sequences clustered in a clade that was close to the Bartonella sp. detected in G. soricina, which was collected from the Cerrado biome in Tocantins, Brazil. Despite a low prevalence of the detected infection, results indicated that neotropical bats from the Atlantic Forest were potential hosts of Bartonella spp., which might be related to the maintenance of a wild enzootic cycle of the bacterium. Additional studies, particularly on bats of genus Glossophaga, are required to elucidate the dynamics of intraspecific relationships between etiologic agent-vector-hosts.

Objetivou-se avaliar e descrever a resposta vacinal ao vírus da hepatite B em população do município de Melgaço, estado do Pará. Tratou-se de um estudo transversal, descritivo, com inquérito individual para determinação da resposta vacinal por meio dos marcadores sorológicos HBsAg, anti-HBc total e anti-HBs por enzimaimunoensaio em 407 amostras. A faixa etária variou entre 01 e 101 anos, onde 57,7% eram do sexo feminino. O anti-HBs isolado com valores ≥10mIU/mL, foi detectado em 27,3%, indicando proteção vacinal contra o VHB; 63,6% eram suscetíveis a infecção, entre esses,23,2% possuíam carteira de vacinação com esquema completo de três doses, não apresentando títulos de anticorpos que confirmasse a efetividade do esquema recebido.Os achados revelaram que a resposta vacinal nessa população foi menor que a esperada, sugerindo a necessidade de adaptar estratégias de vacinação às condições locais para garantir uma cobertura mais eficaz.

The Amazon Basin was historically hyperendemic for HBV and HDV, associated with severe outcomes like fulminant hepatitis. Brazil initiated its hepatitis B vaccination in 1989. This study assessed the current prevalence in this endemic region to evaluate the impact of vaccination. A cross-sectional population-based survey enrolled 1100 urban and rural residents. HBsAg prevalence was 1.5%, with no cases in individuals under 20 years, demonstrating interrupted vertical and horizontal transmission. Anti-HBc positivity (30.9%) indicated past exposure, predominantly in those over 30 years. Isolated anti-HBc (10.3%) included two occult HBV infections. HDV coinfection occurred in 25% of HBsAg-positive cases, with HDV RNA detected in two. Anti-HDV positivity was exclusive to adults over 30. Vaccination coverage was poorly documented, but 23.7% had protective anti-HBs titers. HBV vaccination has reduced HBsAg prevalence from high to low endemicity in the region, eliminating chronic infections in younger generations. Persistent HDV in older age groups underscores the need for targeted screening. Despite vaccination record gaps, the findings highlight the program’s success in interrupting transmission and support continued efforts toward HBV/HDV elimination.