Feline Immunodeficiency (FIV) Virus

Veterinary Nurse

HAS MY CAT GOT FELINE AIDS?

Being FIV positive is not the same as having feline AIDS. AIDS describes the terminal stages of disease, which may not occur for many years. FIV positive means that the virus has infected your cat.

ARE MY FAMILY AT RISK?

No, though HIV in man belongs to a similar group there is no risk of cross infection.

ARE OTHER CATS IN THE HOUSEHOLD AT RISK?

Risks to other cats in the household are low unless the cat that is infected is a fighter. The virus does not survive long in the environment, so disinfection is not of great value. It is advisable that the positive cat is fed from a separate food bowl as saliva can contain large amounts of virus. Generally, however, spread between cats through social contact is very poor so the majority of your cats may well be FIV negative.

HOW DO CATS GET FIV?

FIV is transmitted primarily by biting, cats which are known fighters; particularly those with a history of cat bite abscesses have a risk of being FIV positive. Kittens can also be infected at birth through virus that is present in the queen ’s milk. Around a quarter of a third of kittens born to an infected queen are likely to be infected themselves. Normal social interactions such as grooming have a very low risk of transmitting FIV.

HOW IS FIV DIAGNOSED?

FIV is diagnosed on a blood test by looking for an immune response (antibodies) to the virus. If this test is positive it is likely that your cat is infected by the virus. False positive and negative results do occur for a variety of reasons e.g. antibodies to the virus present in the blood stream of an infected queen will pass via the milk into her kittens giving a positive test result in the kittens, which may not be infected. Kittens under four months of age that test positive should therefore be retested when they are six months old. More specialised tests are also available at external laboratories (which your vet can send samples to) to detect the virus itself and these tests are very sensitive. Virus isolation can also be performed. If the initial antibody test is in any doubt or given a confusing result then your vet may request an additional confirmatory test is performed to ensure that the correct diagnosis is reached.

WILL MY CAT RECOVER?

As far as we know, once a cat is infected with the virus it will remain infected for the rest of its life, though it is not clear if all infected cats will become ill.

WHAT TYPE OF DISEASE DOES FIV CAUSE?

FIV causes disease because it destroys the cat’s immune system so it becomes unable to respond to other infections in the normal way. This means that cats with many types of disease can be FIV positive, such cats are characterised by chronic or recurrent infections that fail to respond to treatment in the normal way. Common clinical signs of FIV infection include:

  • Gingivitis/stomatitis (inflammation of the gums/mouth)
  • Weight loss
  • Poor appetite
  • Fever
  • Inflammation of the membrane around the eyes (conjunctivitis)
  • Swollen lymph glands
  • Vomiting and diarrhoea

A lot of these signs are very non-specific and many diseases can have a similar clinical picture.

IS THERE ANY TREATMENT?

Secondary infections can be effectively treated with antibiotics etc., but no specific treatment for the virus is available. Some cats have been treated with human anti-HIV drugs such as AZT with limited success. Evening primrose oil seems to be helpful particularly in the earlier stages following infections. Recombinant Feline Omega Interferon is the first veterinary Interferon available on the European market and has antiviral and immuno-modulatory (adjust the immune response) properties. To date there are no completed scientific studies as to the effectiveness of this product, but anecdotally there have been some positive reports of its usefulness in treatment of FIV infected cats.

SHOULD I HAVE MY CAT EUTHANASED?

Generally this is not necessary until the late stages of the disease. Like HIV, cats with FIV have a long period where they appear healthy and show no clinical signs. This period can last for two to five years or perhaps even longer during which your cat can have a normal, happy life.

HOW CAN I HELP MY CAT?

You can help your cat by ensuring it has a healthy life style and good quality food together with regular worming and yearly booster vaccination. Any infections should be treated promptly and aggressively. The healthier a cat is the longer the asymptomatic period tends to be. Keeping your cat indoors is also a good idea as it reduces the likelihood of your cat picking up infections from other cats as well as reducing the spreading of the virus from your cat to other cats.

Should you wish to discuss any of these issues in more detail, please consult your veterinary surgeon.