The following information was written by Kari Peters based on a presentation by Dr. Eric Johnson, DVM at the Koi Health Management Seminar at the University of Georgia on February 9-11, 2007

KHV is a virus particle that lives mainly on the epidermal cells of Koi (Cyprinus Carpio).  The virus does not spontaneously occur - it is passed from one fish or pond system to another.  This virus is usually asymptomatic in water temperatures below 70 degree Fahrenheit.  No one symptom is pathognomonic (defines the appearance of the virus), but when it occurs it will likely annihilate a great majority of the Koi in your pond.   Depending on the pond water temperature, signs and symptoms may start to occur within 5-7 days, and most stock will be dead by 10-14 days.  Some of the symptoms of KHV include, rotten gills, peeling and abraded skin, ulcers ringed in black, tail-up comportment, fearlessness, and death.  The virus loves epidermal cells and causes the epidermis to come off the fish.  The fish usually dies osmotically or due to secondary infections.  The most consistent symptom in Koi with KHV is the damage caused to the gills.  The gills have large areas that are discolored, grey or green, or the gills are even gone.

KHV exists in all areas of the world where carp are present, but there are ways to protect your fish and your pond from getting or passing on the virus.

• Always quarantine new Koi in a separate pond and filter system, away from your Koi pond for a minimum of 2 weeks
• Heat the quarantine pond to 74 degrees Fahrenheit, and keep it heated during the entire quarantine process.  If you purchase a Koi in cool water without using this quarantine procedure, once your pond warms during the summer season it is possible to 'activate' the virus and kill most of your Koi.
• If any symptoms related to KHV occur in your fish, immediately have the fish tested for the viral antibodies by rushing the fish to  the veterinary testing facility in Georgia - information on this can be found at www.koilab.com .  Click here for a sample of the Koilab Submission Form
• Any survivors of the virus can be considered 'carriers' and could infect other fish with this virus.
• Always buy your Koi from reputable Dealers who quarantine, heat, and scrape their fish upon arrival into their facilities before selling to their customers.  Ask every Dealer what their quarantine procedure is and how long they have had their fish.

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