Detection and pathotyping of a recent Newcastle disease virus outbreak in Egypt

Document Type : Original Article


1 Department of virology, Faculty of Veterinary Medicine, Benha University

2 Veterinary Serum and Vaccine Research Institute, Abbassia, Cairo


This study was conducted to detect and pathotype Newcastle disease virus (NDV) isolates from a recent
outbreaks affecting poultry farms in Egypt between 2013 and 2014. Trachea, liver and brains were
collected from clinically infected NDV three different vaccinated broiler farms in Sharqia Province. The
reverse transcription polymerase chain reaction (RT-PCR) using fusion (F) gene specific primers were
more sensitive than haemagglutination (HA) in the detection of NDV in collected samples. Inoculation
of all the collected samples in 10-day-old embryonated chicken specific-pathogen-free eggs resulted in
isolation of haemagglutinating agents in 18 samples. These haemagglutinating agents were confirmed
as NDV by haemagglutination inhibition (HI) test. The intracerebral pathogenicity index (ICPI) revealed
that all isolates have a range >1.5 index which congruent to velogenic type. These results confirmed that
the circulating NDV strains are virulent for chickens and vaccination failures occur