What Is Carp Pox?

What Is Carp Pox?

Carp pox is a cold water viral infection that fish get. The virus was typically seen in carp, therefore called carp pox. However, it is not limited to only carp. In fact, many koi owners are quite familiar with this virus.


Keep fish, especially koi, in heated water during winter months. Frequently disinfect any equipment you use for handling your fish. This prevents the spreading of the infection to other fish that do not have it.


Carp pox will be easily visible in fish. It can be described as milky or waxy looking spots or lumps on a fish's body. The lesions can be on a fish's fins, body, or both. In some cases fish appear to be almost completely covered in the unattractive lumps. In fish like koi, that are admired for their beauty, carp pox is noticed easily by fish owners.


If fish carp pox, separate infected fish and put them in a tank for treatment. Gradually warm the water in the tank, water may get as warm as high 70s to 80 degrees. A small amount of salt added to water can also sometimes help fish with illnesses. After a few days to a week, the lumps should start to break up or diminish.

A vet may be able to answer some questions for you concerning carp pox, however there is no prescription that can give you. No medicine or chemicals can cure carp pox. Warm weather and a fish's immune system are the only known things to cure carp pix.

It isn't fatal unless it causes a fish to develop another infection. If carp pox becomes more extreme and doesn't improve, it can leave a fish with a weakened immune system. There are a lot of infection and parasites that are common in all types of fish and a weakened immune system is more likely to develop another health issue. That is way it is best to put fish in warm water as soon as carp pox is detected.

The information provided on this site is for informational purposes only and is not intended as a substitute for advice from your veterinarian or other health care professional. You should not use the information on this site for diagnosis or treatment of any health problem or for prescription of any medication or other treatment.