One-step RT-PCR for the detection of infectious bursal disease virus in clinical samples

A single-tube, non-interrupted, one-step RT-PCR has been standardized to am plify the hypervariable region of the VP2 gene sequence of infectious bursa l disease virus (IBDV). The technique standardized on purified viral RNA wa s successfully applied to the detection of the virus directly in clinical s amples. The amplified products were confirmed to be IBDV specific by their size in ethidium bromide-stained agarose gel, nested PCR and restriction en zyme digestion. Digestion of the amplicons with StyI restriction enzyme als o differentiated classical virus from six very virulent field isolates. The sensitivity of the one-step RT-PCR was found to be 0.2 pg of viral RNA.