Influenza aviária e os impactos para a avicultura no Brasil

Abstract

Avian flu is a disease that has affected animals and humans for over a century. The Influenza A virus has many subtypes capable of infecting a diverse range of animals, birds and mammals, including humans. Wild birds are the main natural hosts, especially waterfowl, and the migratory movement of some species contributes to the spread of viral subtypes to different countries of the world. Most cases of avian influenza are of low pathogenicity, causing mild or no symptoms, however some subtypes are highly pathogenic and can cause severe symptoms and even the death of thousands of birds. In this case, when it affects poultry, the disease can lead to low productivity or huge losses in the meat and eggs production chain. Until recently, cases of highly pathogenic influenza A had not been detected in South American countries, but the H5N1 subtype has spread and also arrived in Brazil. The Ministry of Agriculture, Livestock and Food Supply released an alert for people not to approach sick or dead wild birds, under the risk of contracting the disease. Detection in seabirds has already occurred in several cities in the country, but there is still no evidence of transmission to domestic birds, which would put poultry farming at risk both in the country and in the state of Paraná, the largest national producer of poultry meat. This study aimed to review the world scientific literature about avian influenza and its impact on poultry farming in Brazil. Searches were carried out on scientific platforms regarding the avian influenza virus, from its historical context to the present day, showing the characteristics of the virus, forms of transmission, diagnosis and viral pathology. We sought to highlight and emphasize the need for strategies to monitor the circulation of the virus, as well as studies that can estimate the impacts related to the public/animal health and economic sectors.