FeLV in cats

What is FeLV?

Feline leukaemia virus (FeLV) is an incurable viral infection in cats. It damages the immune system by attacking the bone marrow, making cats vulnerable to:

• anaemia
• cancer (such as lymphoma and leukaemia)
• infections
• immune-mediated disease

Sadly, there is no cure for FeLV and it is almost always fatal. It's estimated that the majority die within four years of FeLV detection. It's important to take steps to protect your cat from FeLV by getting them vaccinated.

There is no risk of FeLV infection to humans.

How is FeLV prevented?

Vaccinating your cat can protect them from FeLV. Vaccinations are recommended for all cats who spend anytime outdoors. Cats that never go outside are much less likely to be infected. Cats can start their first course of vaccinations anytime from 8 weeks of age, and regular boosters are required throughout their life.

If you are planning to get a new cat, you can consider a blood test to check for FeLV before introducing them to other cats in your home.

More on vaccinations

What are the symptoms of FeLV?

FeLV can cause a wide range of symptoms including:

• low energy (lethargy)
• fever
• diarrhoea
• vomiting
• pale gums and eyes (anaemia)
• lack of appetite
• weight loss
• poor coat condition
• chronic or repeated illnesses

More serious symptoms can develop over months or even years. Speak to your vet for advice if you spot any of the above symptoms.

How is FeLV infection diagnosed?

FeLV is diagnosed through a blood test. Tests can be carried out at any age from birth.

Most vets can offer a simple in-house blood test, which will give a quick result. However, sometimes, these tests can give false positive and negative results. Your vet may need to send a sample to a lab to confirm the result, or repeat the test after a few weeks to check and see if your cat is definitely infected

How do cats catch FeLV?

FeLV is found in saliva, urine and other secretions of infected cats. It is spread through cats in close contact, by grooming, licking, biting or by sharing food and water bowls or litter trays.

FeLV can also be spread from an infected pregnant cat to her kittens while they are in the womb, or through her milk. Kittens and young cats are more susceptible to the virus than older cats, as the body’s resistance to FeLV increases with age. But infection in older cats can still occur.

How is FeLV treated?

Sadly, there is no cure for cats infected with FeLV. It's likely that your cat's lifespan will be shortened, but there is no way to know how long your cat will live if they are currently healthy. 

Cats with FeLV are also prone to cancer and serious infections, and may not always respond to treatment. If they are very unwell or have a poor prognosis, euthanasia may be the kindest option.

How is FeLV managed?

If you have a cat infected with FeLV, you can help keep them healthy by trying to reduce the risk of infection. You can do this by: 

• keeping them indoors
• avoiding foods that may carry bacteria (such as raw meat)
• taking them for regular check ups at the vet

Tips for keeping your cat indoors

Cats who live indoors still need to exhibit their natural behaviours. If your cat has FeLV and you're worried about how to keep them healthy and happy, here are some tips:

• Make sure to block all exits such as windows and cat flaps. When you first confine your cat indoors, they may be alert to opportunities to escape.
• It's best to provide your indoor cat with at least two litter trays. Place your cat's litter trays in a quiet area away from their food bowl. If your cat is shy or you have a busy household, a covered litter tray may help your cat to feel more at ease when toileting.
• To reduce the risk of damage to furniture, provide your cat with a scratching post
• Provide additional hiding and resting places for your cat
• Provide your cat with plenty of activities to reduce boredom and keep them fit. Make sure to play interactive games with your cat, such as pulling string toys. If your cat is food motivated, you can also use a food ball for them to chase.

More on indoor cats

My last cat died from FeLV. When is it safe to get another kitten?

FeLV virus does not survive well in the environment, so with good cleaning of food bowls, bedding and litter trays, you should be able to get a new kitten or cat as soon as you are ready. If you have other cats, you may wish to test them for FeLV before introducing any new cats to your home.