Megalocytivirus

Also known as: Infectious Spleen and Kidney Necrosis Virus (ISKNV) group

Megalocytivirus is a genus within the Iridoviridae family affecting various species of marine and freshwater fish. These viruses are characterized by hypertrophic cells (megalocytes) in infected organs. Megalocytivirus infections are systemic and cause necrosis of spleen and kidney tissues, especially in young or stressed fish. The disease has led to significant losses in aquaculture across Asia and other regions.

Distribution: Asia, Australia, and other parts of the world with marine aquaculture
Hosts: Various freshwater and marine fish species (e.g., grouper, seabass, ornamental fish)
Detection Methods: PCR – unspecified; Histopathology
Target Tissue: Spleen, kidney, liver