ABSTRACT
ABSTRACT: Although, serological studies for leptospirosis in iguanas have already been performed, there is no report in the Amazon region. Therefore, the present study aimed to investigate the presence of anti-Leptospira sp. in free living Iguanas-verdes (Iguana iguana) of Mangal das Garças Park, metropolitan region of Belém, Pará, Northern region of Brazil. Twenty-nine blood samples of Iguana-verde (I. iguana) were collected from Mangal das Garças Park. For the serological diagnosis of Leptospira sp. it was employed microscopic agglutination test (MAT) with 25 live antigens of Leptospira sp. as antigens. It was observed that all samples were non-reactive, suggesting no exposure to the agent.
RESUMO: Embora estudos sorológicos para leptospirose em iguanas já tenham sido realizados, não a relatos na região amazônica. Portanto, o presente trabalho teve como objetivo pesquisar a presença de anticorpos anti-Leptospira sp. em Iguanas-verdes (Iguana iguana) de vida livre do Parque Mangal das Garças, região metropolitana de Belém, PA, e Norte do Brasil. Foram coletadas 29 amostras de sangue de Iguana-verde (I. iguana) que frequentaram o Parque Mangal das Garças. Para o diagnóstico sorológico da infecção por Leptospira sp. foi empregado o teste de aglutinação microscópica (MAT) com 25 antígenos vivos de Leptospira sp. como antígenos. Observou-se que todas as amostras foram não reagentes, o que sugere não exposição ao agente.
ABSTRACT
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.