RESUMO
Avian influenza virus (AIV) represents a major concern with productive implications in poultry systems but it is also a zoonotic agent that possesses an intrinsic pandemic risk. AIV is an enveloped, negative-sense and single-stranded RNA virus with a segmented genome. The eight genomic segments, comprising the whole genome, encode for eleven proteins. Within these proteins, Hemagglutinin (HA) and Neuraminidase (NA) are the most relevant for studies of evolution and pathogenesis considering their role in viral replication, and have also been used for classification purposes. Migratory birds are the main hosts and play a pivotal role in viral evolution and dissemination due to their migratory routes that comprise large regions worldwide. Altogether, viral and reservoir factors contribute to the emergence of avian influenza viruses with novel features and pathogenic potentials. The study aimed to conduct surveillance of AIVs in wild birds from Peru. A multi-site screening of feces of migratory birds was performed to isolate viruses and to characterize the whole genome sequences, especially the genes coding for HA and NA proteins. Four-hundred-twenty-one (421) fecal samples, collected between March 2019 and March 2020 in Lima, were obtained from 21 species of wild birds. From these, we isolated five AIV from whimbrel, kelp gull, Franklin's gulls and Mallard, which were of low pathogenicity, including four subtypes as H6N8, H13N6, H6N2 and H2N6. Genetic analysis of HA and NA genes revealed novel features in these viruses and phylogenetic analysis exhibited a close relationship with those identified in North America (US and Canada). Furthermore, H2N6 isolate presented a NA sequence with higher genetic relationship to Chilean isolates. These results highlight that the geographical factor is of major relevance in the evolution of AIV, suggesting that AIV circulating in Peru might represent a new site for the emergence of reassortant AIVs.
Assuntos
Charadriiformes , Vírus da Influenza A , Influenza Aviária , Animais , Animais Selvagens , Aves , Hemaglutininas/genética , Neuraminidase/genética , Peru/epidemiologia , FilogeniaRESUMO
Un total de 360 muestras de sueros de reproductoras de carne y postura procedentes de 18 lotes de aves, en etapa de producción, fueron examinadas con el fin de detectar la presencia de anticuerpos contra el virus de la laringotraqueitis infecciosa aviar (VLT) mediante una prueba de ELISA indirecta. Las granjas de aves estaban localizadas en la región de Lima y en la costa norte del Perú. Los sueros se colectaron entre julio de 2004 y septiembre de 2005 y fueron analizados en conjunto. Ocho de 360 sueros fueron positivos a anticuerpos contra el VLT. Teniendo en cuenta que las muestras positivas procedían de seis lotes de reproductoras y la baja positividad en estos lotes, se concluye que los 18 lotes de reproductoras analizados no mostraron evidencia serológica de exposición al VLT.
A total of 360 serum samples from eighteen flocks of broiler and layer breeders in phase of production were used in order to detect the presence of Laryngotracheitis virus (VLT) antibodies using a commercial ELISA test. The poultry farms were located in the region of Lima and in the northern coast of Peru. Samples were collected from July 2004 till September 2005 and were processed as a group. Eight samples out of 360 in 6 flocks were positive to antibodies against VLT. Due to the small number of positives and the low level of antibodies was concluded than the 18 breeder flocks did not show serological evidence of exposition to VLT.
Assuntos
Animais , Anticorpos , Aves Domésticas , Carne , Ensaio de Imunoadsorção Enzimática , Herpesvirus Galináceo 1 , Postura , SorologiaRESUMO
A total of 180 serum samples collected in the period of April to September, 2004 from 12 broiler breeder flocks and commercial layers older than 50 weeks of age from ten poultry farms were tested for the presence of Reticuloendotheliosis virus (REV) antibodies using a commercial ELISA test. Only 3 samples were positive to antibodies against REV; however, the optical densities of the 3 positive samples were higher than the negative controls but below to the positive controls. ELISA serologic testing is not definitive and, therefore, it can be concluded that the 12 flocks were negative to REV antibodies. On the other hand, further studies, such as isolation and identification of the virus, are required to achieve a definitive diagnosis.
