Dangerous Viruses That Can Affect Your Cat

The viruses that cause feline leukemia and feline AIDS are similar in that they cause immune suppression. Both viruses hold down an infected cat's natural immunity to disease. Your cat's mouth, nose, lungs, skin and intestines are normally covered with bacteria and viruses. However, the normal immune system keeps these bacteria in check and prevents disease. In feline AIDS or feline leukemia, that natural immunity is reduced to the level that allows any bacteria or virus to multiply and cause disease.

Feline Leukemia Virus (FeLV)

Overview

One of the most dangerous infectious diseases in cats today is caused by the feline leukemia virus (FeLV). FeLV is a retrovirus that is specific to cats only and is the most common cause of serious illness and death in domestic cats. It suppresses the immune system, impairing your cat's ability to fight infections. It may also cause anemia, leukemia and some forms of cancer.

FeLV cannot be transmitted to humans (including children) or other species such as dogs.

FeLV is spread by contact through the saliva, tears and urine by way of bite wounds, shared dishes or litter pans, or close contact (grooming). Kittens can be born with FeLV or acquire the virus through their mother's milk.

What To Look For

There are no specific symptoms that will tell you that your cat has FeLV. Your pet may develop a fever, poor appetite, lethargy, or suffer from recurring infections. He will most likely lose weight and suffer from a skin condition. Symptoms may include:

Pale gums

Weakness

Lethargy

Diarrhea

Weight loss

Anorexia

Breathing difficulties

Increased thirst and neurologic abnormalities

Diagnosis and Treatment

FeLV is easily diagnosed by a simple blood test, and you should test all new cats for this virus. Once your cat tests negative, a vaccine is available to help reduce the risk of infection with the virus. Although it is not 100 percent effective, the vaccine does offer immunity to most cats and has minimal side effects.

You should vaccinate all cats 10 weeks or older who are likely to be at increased risk of becoming infected. This includes cats that spend any time outdoors, in multiple-cat households, or at catteries and cat shows. If your cat is strictly indoors, you may want to discuss the need for FeLV vaccine with your veterinarian. FeLV and rabies vaccinations have been implicated in the very rare injection-site sarcoma syndrome.

Feline AIDS (FIV)

Overview

Feline immunodeficiency virus, or FIV, is a widespread viral infection that attacks the immune system of cats. It is caused by the same family of viruses that trigger AIDS in humans and has much the same devastating impact on infected cats. It is often referred to as "feline AIDS." The virus ravages a cat's immune system, stopping it from effectively combating other diseases and infections. Infected cats eventually fall prey to a wide variety of secondary illnesses that overwhelmingly prove fatal. FIV is not transmissible to people or dogs.

The disease is transmitted from cat to cat by blood and saliva. Cats can transmit FIV to other cats only through biting, not through urine or casual contact, so outdoor and male cats that fight with other cats are at greatest risk. FIV has also been found in mother's milk and can be transmitted from mother to kitten. The virus itself is easily disinfected and dies within minutes upon exposure to dry surfaces.

What To Look For

Signs that your cat is infected are primarily related to the effects of diseases contracted when the body defenses fail. Ultimately, widespread organ failure occurs, and the cat dies.

Severe infection affecting the gums

Abscesses from fight wounds that don't heal

Respiratory infections

Weight loss

Poor appetite

Unkempt coat

Diarrhea

Diagnosis and Treatment

A blood test can identify infection. This test is usually performed when your cat is tested for FeLV. A positive test means the cat has been exposed to the virus and will likely be infected for the remainder of his life.

Unfortunately, no vaccine against FIV is available at this time and there is no cure for the disease, but cats can live for up to 10 years – much of it in seemingly good health – before succumbing. However, the virus will still be in the cat and may become active at a later date. Therefore, the long term prognosis is not good.

The best protection from FIV is prevention. Keep your cat indoors and have him or her neutered, because neutered cats tend to fight less. Most importantly, have all new cats or kittens tested for the virus before introducing them to your cats at home.