Isolation and characterization of low pathogenic H9N2 avian influenza A viruses from a healthy flock and its comparison to other H9N2 isolates

摘要: Several outbreaks of avian influenza (AI) caused by H9N2 subtype, have been reported in the poultry industry during 1990 around globe. Currently, are endemic large area Middle and Far East, including Pakistan. Since AI viruses sporadically from humans, extensive incidence imposes a great risk for human health. In this context, continuous monitoring determining genetic nature these fundamental to predict any future threat. Thus gene sequences one isolate H9N2, isolated commercial flocks, were analyzed. The results investigation, based on hemagglutinin (HA), neuraminidase (NA) non-structural genes, showed that Pakistani isolates closely related each other East. However, several unusual substitutions with unknown functional consequences observed HA NA proteins thus warrant further investigations their possible role viral biology. conclusion, findings provide information regarding necessitate sequencing more both naturally infected vaccinated flocks.