---Update 6/4/2024

Details on Restocking assistance have been finalized and can be found at the link below. All potentially affected customers will be emailed the link as well.

Restocking Assistance


---Update 6/3/2024

All infected systems have been emptied and sanitized thoroughly.  We have new fish in Quarantine that will be PCR tested this week and pending negative test results we hope to begin photographing and resuming sales and shipping next week. Please look for new fish to be added to the website starting on June 12th. All currently listed fish have been euthanized and will be removed from the website in time.  

Source of Infection

At this time we believe Koi that were vaccinated against the KHV virus were the source of the outbreak.  We were assured there was no risk of vaccinated fish spreading the virus and that in 20+ years of vaccinating fish being sold all over the world there had never been a known instance of this happening. 

Though vaccinated fish have never been common or popular in the United States they have been very prevalent in Europe and other parts of the world. Dealers in those countries have sold and mixed vaccinated fish with non vaccinated for many years with no records of any infections happening.

We brought in vaccinated fish for the first time in March/April this year and for over a month we saw no sign or symptoms of the virus. Only after finding out about other companies also bringing in vaccinated fish and seeing infections did we see any symptoms on our end. This coincided with our decision to cease sales and shipping. We saw a 3 day spike in fish losses and lost around 10% of the fish in the infected systems. Deaths stopped and most of the remaining fish did not appear sick or show any signs.  A few days later we received positive test results and proceeded with euthanizing and disinfecting. 

As stated above, we strongly believe that somehow the virus was transferred from the vaccinated fish to the non vaccinated and ultimately has affected some of our customers. We still do not have any evidence explaining what circumstances allowed for the virus to be shed by the vaccinated fish.

We are very sorry to those that have been affected by this virus and we are communicating with those who have been in order to make this right.  We appreciate all of the understanding and kind words from our customers, friends and others in the industry during this time.  We are here to help.

Moving Forward

Effective immediately we will be only purchasing and selling fish from Indoor Bio Secure farms.  Indoor Bio Secure fish are the safest in the world. These facilities have been closed off and no new fish have brought in for almost 20 years. Fish only leave these facilities.  These facilities are tested multiple times per year for KHV and other viruses by the Israeli Ministry of Agriculture. We will also be doing testing on our end for all shipments we receive.

Restocking Assistance

We are currently working out the final details for assisting affected customers in restocking their ponds.  Please keep photo records of any losses.  The photos should show clearly the color, pattern and size of the fish. Please place a ruler or tape measure next to any fish you photograph.



---Posted 5/17/2024

On Saturday May 11th, 2024 we were notified that other Koi dealers in the US had positive test results for the KHV virus.  We reached out to one of those dealers and confimed that we had also received fish from several of the same suppliers as them.  Upon learning this information we decided to immediately cease the shipping of all pending orders until we investigated the situation and had our fish tested for the KHV virus. Samples were overnighted to the University of Georgia Infectious Diseases Laboratory for PCR Testing. 

Positive Test results were received back to us on 5/17/2024. The virus is present in at least some of our systems.  Additional testing will be done on systems that did not test positive.

All pending orders are being cancelled and refunds issued.  All fish from the infected systems will be euthanized and the systems will be disinfected thoroughly.

What is KHV?

Koi herpes virus or KHV is a highly transmissible, incurable and deadly virus that affects all strains of common carp, including koi and butterfly koi.

Can KHV be Cured?

There is no known cure for a KHV infection. Heating tank or pond water to 86°F has been shown to stop mortality in infected fish and help the fish to recover. Fish that recover after heat treatment may still be carriers of the virus and contagious to other fish.

How Can I tell if my fish were infected? What are the symptoms?

KHV shares many of the same symptoms that are caused by other routine and treatable parasite and bacterial issues. If you have fish with symptoms, it is important to rule out other possible causes via microscopy and treatment before assuming that you have a KHV infection.

KHV symptoms can include “difficulty breathing, gathering near oxygen-rich areas (such as waterfalls or aerators), excessive mucous production from gills, swollen gills, gill necrosis/discoloration, ulcerations, reddened skin/fins/tail, pale patches, sloughing of scales, increased/decreased mucous production, ‘sandpaper’ texture to the skin, decreased appetite/refusal of food, lethargy, sunken eyes, erratic swimming, and ‘hanging’ with a head down position.”1

The only way to know for certain if a fish is infected is to submit a biological sample for PCR testing. Information on PCR testing can be found further down below.

How Long before symptoms appear?

KHV outbreaks typically occur when water temperatures are between 60° and 77°F (16° and 25 °C) with an incubation period of 7–21 days depending upon water temperature. Colder or warmer water may hide the virus for longer periods of time.

Can my fish be tested?

Yes. There are 3 laboratory's that we are aware of that perform real time PCR testing. Links to those labs testing procedures and instructions are included below.

While several different types of samples can be submitted for testing, it may be easiest to submit a gill cutting. To submit a gill cutting, use small surgical scissors to remove a portion of the gill. Enclose the gill tissue in a sealed container, and send the sample along with the required paperwork to a laboratory listed below per their specific instructions via UPS or Fed Ex overnight. Samples must be kept cold.




If you do submit a sample for testing, please share the results with us once they are returned to you.

Will Koi Fish USA help me test my koi?

We are not able to facilitate or fund testing at this time.

All of our fish are covered by a 14 day health guarantee that is now extended to cover any fish received after April 22nd.  If you are experiencing any health issues with fish received prior to April 22nd please contact us with that information and we will discuss a solution with you.

How do I know if my order was at risk of being infected?

We cannot say for certain with the information that we currently have.  Based off our test sample dates and the incubation period of the virus we can only say that fish you received after April 22nd are potentially at risk of being infected by the virus.  Please monitor your fish closely for any signs.

What should I do?

If your fish are still in quarantine, you can leave them there until more information is available and we all have a better understanding of the situation. You may also choose to have your fish tested for KHV at any of the laboratories listed above.

If you choose to euthanize a fish received from us between April 22nd and May 10th, you can submit photos to us for a refund.

If you made the decision to forgo quarantine and add new fish directly to your primary tank or pond, we are not aware of any action that you can take to reduce or eliminate the possibility of infection.

Will I be refunded for fish I received?

We are extending our Guarantee to cover any sick or dying fish that were received between April 22, 2024, through May 10, 2024. 

Please email us details of fish that were lost outside of the refund period, and we will review these on a case-by-case basis in the order they were received.

What happens if fish I previously had also die?

We can only issue refunds for fish purchased from us between April 22–May 10, 2024. While we can’t refund you for fish purchased from other vendors, we can work with you to help you restock.

Do I need to disinfect my pond?

If your fish are currently healthy and not displaying symptoms, there is no immediate need to dispose of your fish and disinfect your system. If you choose to disinfect or feel that you must disinfect your system, these are the directions that we have received from another online source:

In order to disinfect a tank or pond, dispose of every fish. Run bleach solution through the entire system for 24 hours at dosage of 1 cup per 1,000 gallons. Drain system and spray tank or pond with bleach solution, let sit for 24 hours and then rinse well. Fill system or pond back up and treat with Cloram X or other sodium thiosulfate product to neutralize chlorine and make the system safe for fish again. Follow manufacturer’s recommended dosage for Cloram X or other sodium thiosulfate product.

If I choose not to disinfect my pond will I always have KHV?

A virus needs a host to live in. If every susceptible fish in a tank or pond dies and there are no live common carp left in the pond, then the virus does not have a host to infect, and the virus will die out.

Can Goldfish & other fish get the virus?

All Koi and Butterfly Koi are the same species of common carp and are susceptible to KHV infection. It is our current understanding that goldfish cannot be infected and cannot transmit the KHV virus. While goldfish cannot become infected and shed the virus, it is possible the virus can exist on any surface in an aquatic environment, which includes goldfish.

How Often does this happen?

KHV was first documented in common carp in 1998. Many Koi farms and Koi dealers around the world have been affected in the decades since. Some years are worst than others with the last major outbreak being in 2018-2019 that affected numerous dealers in the US.  This is our first experience dealing with the virus since we first started in the koi business in 2004. 

What as the source of the infection?

At this time, we do not have enough information to say with any degree of certainty what the initial source of infection was. We are submitting additional samples for testing to gain more information and ultimately try to form an idea of the initial source. More information will be made available as we have it.

How will you prevent this from happening in the future?

Moving forward we will reduce the number of farms where we bring in fish from and purchase from Bio secure facilities only.  Bio Secure fish are tested numerous times throughout the year for KHV & other infectious viruses.  Bio Secure fish are the safest fish on the planet and it is no longer worth the risk to bring in any fish not from Bio Secure farms.  We will also regularly send out our own samples for KHV testing.

When will you be selling fish again?

We anticipate that we will have our facilities fully disinfected and be back up and running in a matter of weeks. We will send an email when we are accepting orders again.