Feline leukemia (FeLV) in cats

A cat affected by feline leukemia (FeLV) can still live a normal life before becoming ill. The symptoms of FeLV are difficult to detect as they are non-specific, but it is common to get tumours, anaemia and a weak immune system, which in itself leads to other diseases. Diagnosis is made through a blood test.

Cats can carry the FeLV virus for a few years before displaying any symptoms. In fact, it is possible for a cat to infect other cats before showing any signs themselves.

FeLV is a serious disease that impairs the cat's immune system. Infections would be harmless to a healthy cat can be life-threatening to a FeLV-infected cat. A cat with FeLV also runs a greater risk of suffering from various types of infections and tumour diseases than a healthy cat does.

Symptoms of FeLV

• Tumours
• Weight loss
• Weakness
• Fever
• Dehydration
• Diarrhoea
• Red eyes
• Enlarged lymph nodes
• Inflamed gums
• Foetal death
• Skin infections
• Anaemia

The cat's immune system is crucial

When a cat is infected with FeLV, the disease can broadly take three different courses depending on the cat's immune system.

A cat with a very good immune system shows no symptoms and neutralises the virus. The cat then has antibodies that shows they have been infected.

In a cat with a good immune system, the virus remains in the body. It can be reactivated during stress or treatment with drugs that defend the immune system such as cortisone.

Finally, in a cat with a compromised immune system, the virus remains and symptoms can develop. In these cases, the prognosis is poor. Cats can suffer from anaemia or lymphoma, and the immune system deteriorates, which makes them even more sensitive to other infections. Others may live healthy for several years but with a shortened lifespan.