Pathogenicity of an Avian Influenza Virus Serotype H9N2 in Chickens

Avian influenza virus (AIV) infects different types of birds, including chickens, causing respiratory or systemic diseases that vary in severity. Possibly the most significant problem facing the poultry industry in the world at this time is the spread of AIV serotype H5N1. A low pathogenic avian influenza virus (AIV) serotype H9N2 affected many commercial flocks in the Middle East in the late 1990’s and early 2000’s. Due to the varying pathogenicity of AIV H9N2 reported in previous studies, this study was carried out to determine the pathogenicity of a Jordanian isolate of H9N2 in broiler and specific pathogen free (SPF) chickens.