ABSTRACT Wild birds have great prominence in the transmission of diseases to humans, mainly due to their ease of access to human populations, raising concerns about the potential impact of that proximity on public health. The present study reports ARV and PBV occurrence in wild birds from an environmental protection area in the Amazon biome, in Pará state, Brazil. We obtained 155 fecal specimens from 47 species of wild birds for RNA extraction, ARV and PBV detection utilizing molecular methods, nucleotide sequencing, and phylogenetic analysis. ARV prevalence was 0.6% (1/155), being positive in an individual of Myrmotherula longipennis, and PBV prevalence was 1.29% (2/155), affecting two individuals of Guira guira. The PBV strains were assigned to genogroup I based on phylogenetic analysis, and they shared a strong phylogenetic link with strains isolated from different geographic locations. The ARV strain was more closely related to strains that had previously circulated in the same region. The presence of ARV and PBV in this habitat suggests that infection cycles of these agents occur naturally in the wild ecosystem, potentially triggering transmission events between bird species and humans. This is the first study on ARV detection in wild birds in Brazil and the first report on the occurrence of PBV in wild Guira guira. Additional studies are required to determine the epidemiology, origin, evolution, and emergence of new potentially pathogenic viruses in the Amazon.

RESUMO As aves silvestres têm grande destaque na transmissão de doenças ao homem, principalmente pela facilidade de acesso à população humana, levantando preocupações sobre o potencial impacto dessa proximidade no contexto da saúde pública. O presente estudo relata a ocorrência de ARV e PBV em aves silvestres de uma área de proteção ambiental no bioma Amazônico. Obtivemos 155 espécimes fecais de 47 espécies de aves silvestres, que foram submetidos a extração de RNA, detecção de ARV e PBV por técnicas moleculares, sequenciamento nucleotídico e análise filogenética. A prevalência de infecção por ARV foi 0,6% (1/155), sendo positivo em um indivíduo de Myrmotherula longipennis, e a prevalência de PBV foi 1,29% (2/155), afetando dois insdivíduos de Guira guira. A análise filogenética agrupou as cepas de PBV no genogrupo I, mostrando intensa relação filogenética com cepas isoladas de outras regiões geográficas. A cepa de ARV esteve mais relacionada filogeneticamente a cepas previamente circulantes na mesma região. Este é o primeiro estudo sobre detecção de ARV em aves silvestres no Brasil e o primeiro relato sobre a ocorrência de PBV em Guira guira. A circulação de ARV e PBV nesse ambiente demonstra que os ciclos desses agentes estão ocorrendo de forma natural no ecossistema silvestre, o que pode desencadear possíveis eventos de transmissão entre as espécies aviárias e humanos. Estudos adicionais são necessários para determinar a epidemiologia, origem, evolução e surgimento de novos vírus potencialmente patogênicos na Amazônia.

BACKGROUND In this study, we evaluated the role of free-living domestic pigeons (Columba livia) as a reservoir of arboviruses in the city of Belém, state of Pará, Brazil. We investigated the presence of antibodies against the most prevalent arboviruses. OBJECTIVES This study was aimed at evaluating some clinical and physical parameters of domestic pigeons, including the presence of antibodies to Amazon-endemic arboviruses. METHODS Eighty-five healthy pigeons were captured in Mangal das Garças Park, in Belém, and were bled. Upon capture, the birds were subjected to a clinical examination in search of alterations that could indicate the presence of arboviruses. Blood samples were converted to serum and tested using the haemagglutination inhibition (HI) technique with a panel of 19 antigens of arboviruses circulating in the Amazon. The confirmation assay for the positive reactions to the viral species tested by HI was a neutralisation test in new-born Swiss albino mice (Mus musculus) [mouse neutralisation test (MNT)]. FINDINGS A total of 10 (11.8%) serum samples tested positive for antiflavivirus antibodies by HI. All the samples positive for the HI test were subjected to MNT for detection of viruses and yielded negative results (logarithmic neutralisation index < 1.7). MAIN CONCLUSION The results represent the first serological detection of antiarbovirus antibodies in domestic pigeons as potential hosts of arboviruses in Brazil. The detection of haemagglutination-inhibiting antibodies against genus Flavivirus indicated that there was recent contact between the analysed domestic pigeons and these arboviruses. Further studies are needed to evaluate the role of free-living pigeons in the maintenance cycle and spread of arboviruses in the Amazon.