• The Central Institute of Brackish Aquaculture located in Chennai has developed an indigenous vaccine for Viral Nervous Necrosis. The name of the vaccine is Nodavac-R.

Viral Nervous Necrosis :

• The disease is caused by the Betanodavirus. It mostly affects teleost fish. More than forty species are affected by this virus and most of them are marine species.
• This virus transmits through passive diffusion and contact.
• The disease mostly occurs in juveniles or larvae. However, it also affects the adults.

Viral Nervous Necrosis in India :

• In India the disease has been a serious concern affecting freshwater, marine and brackish water fishes largely. They result in 100% mortality in fishes that are in juvenile and larval stages.
• Red Spotted Grouper Nervous Necrosis Virus is the only genotype found in India. The infected adults are the main carriers. They transmit the virus to their offspring through the eggs.