For easy detection of pathogen, the CIFA developed nested RT-PCR based diagnostic kit is found to be advantageous for rapid and sensitive detection of the virus in fish. This PCR based approach can be used for routine diagnosis of the disease in field and laboratory conditions. This kit can be used in disease surveillance, developing control measures and detection of virus in hatcheries and farms. The primers provided have also been checked in real time PCR to increase the sensitivity and specificity of the kit as well as to quantify viral particles in infected tissues.