Rapid Detection of Virulent Newcastle Disease Virusby One Step Reverse Transcriptase-Polymerase Chain Reaction

The one step reverse transcriptase-polymerase chain reaction (RT-PCR) method for detection of virulent Newcastle disease virus (NDV) was developed, and the oligonucleotide primers, selected from the fusion protein-coding gene, amplified the fragments of 170 bp. In these tests, no specific amplification for avirulent NDV, IBV, AIV subtype H5 and IBDV was observed. As little as 10-5-fold dilution of amnio-allantoic fluid containing NDV (approximately 103.7EID50) could be detected with this method. Total of 21 virulent NDV isolates from different areas of Shandong province in 1997～2003 were tested as positive and six avirulent NDV isolates as negative. The process from RNA extraction of virus to result display was completed within five hours. These data suggested that the specific, sensitive and fast method was available for differentiating field case with virulent NDV in chicken.