Fatal diseases of cats

There are four important viruses in cats for which vaccines are available.

Feline Infectious Enteritis

Feline infectious enteritis (also known as panleucopaenia or parvovirus) is a severe disease that fortunately has become much less common thanks to highly efective vaccines.

The disease is usually seen as bloody diarrhoea in young animals, with a characterisic offensive odour and severe dehydration. Many will die within hours of the onset of symptoms.

Once a cat becomes infected by parvovirus, the virus invades the intestines and bone marrow. This leads to sudden and severe bleeding into the gut, resulting in dehydration and shock and damge to the immune system. Death is common and frequently rapid unless emergency veterinary treatment is received. Kittens born to infected mothers are weak, prone to infections and may have permanent brain damage.

Feline Upper Respiratory Disease

This is caused by two important viruses and may be complicated by secondary bacteria. The two viruses are called feline herpesvirus and feline calicivirus, and together they form the disease commonly called 'cat flu'.

Feline herpesvirus will infect most cats during their lifetime, and most cats will become lifelong carriers. They may excrete the virus when they become stressed or ill, causing repeated bouts of illness. Vaccination protects cats from disease, but the immunity does not last long and needs regular boosters for the best possible protection.

The virus attacks the eyes, mouth and lungs, causing severe symptoms such as fever, eye ulcers and pneumonia. The infction is often made worse by secondary bacterial infections. Infected mothers give birth to small, weak kittens.

Feline calicivirus is also very common. It is generally less severe, but causes painful ulcers of the mouth and tongue, and may again be complicated by bacterial infections. Vaccination is highly effective at protecting cats from disease, but regular boosters are required.

Feline Leukaemia Virus

Feline Leukaemia Virus (FeLV) is the biggest killer of cats in the UK apart from car accidents. Infected animals may not show any signs of illness for months or even years, so many more cats may be infected before warning signs are seen.

It is easily spread in saliva and blood, so cats are infected when grooming each other, sharing food bowls and litter trays and when fighting.

Animals are usually infected during the first few months of life, but any age of animal including adults and unborn kittens may become infected.

FeLV attacks the white blood cells and bone marrow. This makes the cat vulnerable to secondary infections. It also causes anaemia and cancer of the blood, intestines and other parts of the body.

One in three cats that catch the virus will develop the disease. Only early vaccination and regular boosters can protect your cat from the virus.