Hemorrhagic Septicemia, or commonly known as VHS (Viral Hemorrhagic Septicemia) or VHSv (Viral Hemorrhagic Septicemia Virus) is a viral disease that not only plagues pond fish and aquarium fish, but also can spread to other animals with the same deadly symptoms. Many times this disease can be mistaken as just a simple injury due to it's symptoms, however as the disease progresses it can spread to everything inside of the same water whether it effects the inhabitant or the inhabitant is just a viral carrier.
Due to the nature in which this viral infection shows itself, it can be almost impossible to identify it at the early stages. However as the fish starts to become more and more weak the chances of seeing and being able to fully identify this disease grow greatly. During the early stages of VHS there are very few symptoms which the fish will show such as sores around the body, the eyes will start to bulge, the fish may appear to be bloated regardless of feeding amount, and/or depending on species the fish may try to stay away from other inhabitants. In further stages of the disease is where there will be the visible signs such as open sores around the body, widespread hemorrhages (bleeding through the skin), gills will appear to be pale, internal organs will appear to be pale, fish will swim near the surface of the water, fish may appear to be lifeless, and/or the fish may swim in circles frequently. Sadly in the last stage of the disease the fish may appear to be fully pale, the body will be fully blood red, eyes may be popped out and more before the disease fully takes over the fish's immune system leading to death.
Hemorrhagic septicemia is one of the few diseases that has no real cause, however it can spread from one fish to another through various means. These can include but are not limited to the fish eating an infected fish's poop, rubbing against the fish, eating an infected fish's body after it has died, eating smaller inhabitants that are carrying the disease, the fish breathing through their gills within water that has been contaminated with the blood of a fish who is infected, and also using equipment that the virus has been laying dormant in (such as reusing equipment without cleaning it properly or not cleaning any equipment that has come in contact with this disease). The best way to avoid having any pond or aquarium inhabitants catching this disease is to always quarantine them fully and buy from a aquarium store or dealer that is reputable in having their livestock in great conditions.
Treatment and Medication
Unfortunately there is no known cure to this viral infection although many have stated that using a bacterial and fungus medication does slow down and can prevent death, there is no known documented proof such medicines do truly work. Since this viral infection plagues many lakes found within different countries, there are many agencies that are still doing tests to find the perfect cure to this virus. If any of your fish do present this viral disease whether they be inside of a pond or aquarium, many agencies will take the death body to do further analysis on what can prevent this disease and how it fully effects the fish. If you would like to help out to find a cure to this viral disease, please contact your local fish and game agency on instructions on what to do with the fish as it is dying, or if it is already dead.
Due to the way that this disease spreads and effects the inhabitants, the best prevention methods are to always make sure that you quarantine anything that you place inside of your water (this includes any plants, inhabitants, decorations, and more). Thus, when you do let them adjust to your water and you truly see how they are acting, eating and if they have any symptoms or signs, we will either start to get a better understanding if they are infected, or learn about what possible other diseases they might have.