Freshwater Fish Viral Haemorrhagic Septicaemia (VHS) is a highly contagious viral disease that affects many species of freshwater fish. The virus causes severe internal bleeding, hemorrhaging, and eventual death. The most common symptom of VHS is red or gray spots on the fish’s body, which could indicate the presence of an infection. Mortality rates can be very high, with mortality rates of up to 100% in some cases.
VHS is primarily spread through water contaminated with the virus, either from infected fish or other sources. The virus can also be spread through contact with equipment or surfaces that have come into contact with infected fish. It’s often difficult to detect VHS in its early stages, so it is important to watch for signs of illness or unusual behavior in fish. Common signs of VHS include lethargy, appetite loss, and erratic swimming behavior. In some cases, fish will also develop hemorrhages on their skin or in their gills.
Symptoms of Freshwater Fish Viral Haemorrhagic Septicaemia (VHS)
- Red or gray spots on the fish’s body
- Internal bleeding
- Hemorrhaging
- Excessive mucus production
- Lethargy and appetite loss
- Weight loss
- Swollen eyes, fins, and gills
Diagnosing Freshwater Fish Viral Haemorrhagic Septicaemia (VHS)
In order to diagnose VHS, a veterinarian will need to take a sample of the affected fish’s blood and tissue. This sample will then be sent to a laboratory for analysis. The analysis will look for specific proteins that are associated with the virus.
Stages of Freshwater Fish Viral Haemorrhagic Septicaemia (VHS)
Stage 1
In the early stages of infection, the virus will spread through the fish’s body but produce no symptoms.
Stage 2
The fish will develop red or gray spots on their body and begin to show other signs of infection such as lethargy and appetite loss.
Stage 3
The virus begins to damage internal organs, leading to severe hemorrhaging and eventual death.
Treating Freshwater Fish Viral Haemorrhagic Septicaemia (VHS)
Unfortunately, there is no known cure for VHS. Treatment options depend on the stage of infection, but typically include antibiotics and supportive care such as increased oxygen levels in the water. In some cases, euthanasia could be the best option to prevent further suffering.
Preventing Freshwater Fish Viral Haemorrhagic Septicaemia (VHS)
The best way to prevent the spread of VHS is to practice good biosecurity measures when keeping fish. This includes regularly cleaning tanks and equipment, and avoiding contact with wild or unknown fish. If a fish does become infected, it should be removed from the tank immediately and placed in quarantine for further evaluation.