FIV (Feline AIDS)

Overview
- FIV is a virus that infects cats and damages their immune system, making them prone to infections that they then struggle to recover from (similar to HIV in humans).
- Sadly, there is no cure for FIV and many infected cats die from infections that a healthy cat would be able to fight. However, FIV usually develops slowly and many infected cats live for several years without symptoms.
- Common FIV symptoms include inflamed gums, ongoing infections and poor general health.
- FIV spreads in saliva, usually when an infected cat bites another.
- Neutering your cat is the best way to protect them from FIV.
- FIV only affects cats and does not transfer to humans or other animals.
General information
What is FIV?
FIV is a virus that infects cats and damages their immune system, making them prone to infections that they struggle to fight (similar to HIV in humans).
How does FIV spread?
FIV spreads in saliva (spit), most commonly via cat bites. It can also spread between cats that groom or lick each other and from a mother to her kittens in the womb and via milk, but this is much less common.
What happens if my cat catches FIV?
Sadly, once a cat has caught FIV, there is no way to get rid of it and it’s likely to cause illness at some point. The good news is that FIV tends to develop slowly and symptoms often take a few years to develop.
Symptoms and diagnosis of FIV
Cats with FIV have a weakened immune system, making them prone to infections that they find difficult to fight off. However, FIV develops slowly and symptoms often take two - five years to develop. Once symptoms start to appear you may notice:
- General ill health
- Repeat infections
- Sore mouth and gums
- Gum disease (gingivostomatitis)
- Low energy (lethargy)
- Chronic diarrhoea
- Swollen lymph nodes (glands)
- Other problems such as kidney disease and uveitis.
FIV can be diagnosed with a simple blood test, likely to be available in your local vet clinic.
Treatment
Sadly, there is no cure for FIV and it nearly always causes illness at some point. Once symptoms start developing, regular vet checks and treatment will be required.
Infections
Cats with FIV have a weakened immune system, making them prone to infections that they find difficult to fight off. Infections in an FIV positive cat can become very severe unless they receive treatment quickly.
Reduce the risk of infection
It’s important to keep FIV positive cats indoors and away from other cats to protect them from infections and prevent spread to others - cat proof enclosures in the garden are an option. You will need to feed your cat a high-quality food and avoid raw meats / unpasteurised dairy products (milk/cream/cheese) which could contain germs. Have regular vet checks (at least every six months), monitor for ill health and take him/her to the vet if you are concerned.
Other
It’s important to keep your cat up to date with worming treatment, flea treatment and vaccines (speak to your vet about the most suitable vaccinations for FIV positive cats).
Anti-viral medication
There are anti-viral medications that can reduce the effect of the FIV virus. However, these treatments are very expensive and many cats appear to do just as well without them.
Outlook
Unfortunately, most FIV positive cats eventually become poorly and die due to infections healthy cats fight off. The average life expectancy once diagnosed is 5-6 years. If you feel you are unable to manage your FIV cat, or they start to suffer/become unwell, the kindest option may be to put them to sleep. Regular vet checks will help to spot problems early and ensure your cat lives a healthy, happy life for as long as possible.
Preventing FIV
There is currently no FIV vaccination available in Europe.
Neutering (castrating/speying) your cat is the best way to protect them from FIV because it significantly reduces the risk of them getting into a cat fight and being bitten. Try to encourage your neighbours to have their cats neutered and keep an eye out for un-neutered cats in your area (especially males). Reduced cost neutering may be available through charities in your area, speak to your vet for more information.
Cost
Ongoing treatment for FIV can become expensive. It’s important to speak openly to your vet about your finances, the cost of treatment, as well as what you think is right for your cat. There are often several treatment options so if one doesn’t work for you and your cat, your vet may be able to offer another.
Consider insuring your cat as soon as you get them, before any signs of illness start. This will ensure you have all the support you need to care for them if they become poorly.
Published: November 2019
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Written by vets and vet nurses. This advice is for UK pets only.
Illustrations by Samantha Elmhurst