• About koi Herpes Virus

    Koi herpes virus (KHV) causes a highly contagious, usually fatal disease of koi and common carp. Experts consider it to be the single biggest threat to koi ponds and the koi industry as a whole. The first case of disease related to KHV was identified in England in 1996, and the KHV virus was isolated two years later. KHV, like the viruses that cause colds and flu in humans, is a very simple form of life. It consists only of genetic material (DNA) and other basic molecules that enclose the DNA.

    Its simplicity makes it hard to control

    Koi herpes is so simple that it can't reproduce on its own but must infect koi cells and “hijack” the cells' internal workings, effectively turning each cell into a virus-making machine. Now consider how hard it would be to control such a disease. In order to kill the virus, you would also have to kill the cells it has infected, so the cure would likely be as bad as, or even worse than, the disease.
    After KHV has infected a cell and reproduced many copies of itself, the newly created viruses rupture the cell and go on to infect other nearby healthy cells within the koi’s body. Because KHV is so effective at reproducing itself and destroying cells, it is a highly effective killer of koi.

    How KHV spreads

    Once KHV has ruptured a cell, many of the new viruses will stay in the body. Some, though, will leave the koi and enter the pond water. Natural forces — like the small currents created as the koi swim through the water and diffusion — will stir the virus throughout the pond, where it will be able to infect even more koi. Because it spreads readily and enters koi cells efficiently, KHV is highly contagious.