Feline Leukaemia Virus (FeLV) is a serious virus which attacks the immune system in cats and can be fatal.
While the outlook for infected cats is generally poor, FeLV can be prevented by keeping cats up to date with their vaccinations, as explained by Sarah Elliott, Central Veterinary Officer at Cats Protection.
What is FeLV and how is it spread?
FeLV is a virus which only affects cats, so it can’t be passed to humans. It can be passed from an infected mother to her kittens, both through her milk and while they are in the womb. It can also be transmitted through saliva – most often when cats share food and water bowls, lick each other while grooming or during mating.
What are the symptoms of FeLV?
FeLV attacks the immune system which in turn leaves cats vulnerable to other infections, anaemia and tumours.
The virus can cause many symptoms, including sore gums, digestive problems, a high temperature, enlarged lymph nodes - which may also be cancerous - and the development of other cancers.
Is there a cure for FeLV?
Once infected, it is possible for some cats to clear the FeLV infection and recover after a few weeks, giving them some immunity in future. However, this is not always the case and many cats – particularly younger or weaker cats – will be permanently infected.
For cats which can’t clear the infection, there is no cure for FeLV but a vet may be able to help manage symptoms to keep your cat comfortable for as long as possible.
What is the prognosis for cats with FeLV?
Because FeLV has a long incubation period, it may be months or possibly years before symptoms appear in those cats which have been permanently infected. However, once signs begin to show, FeLV can progress quickly and 80 percent of cats die within three-and-a-half years of being diagnosed.
Should I have my cat tested for FeLV?
If you suspect your cat may have FeLV, speak to your vet who may recommend a blood test to see if the virus is in the blood.
FeLV vaccine
Fortunately, there is a vaccine for FeLV which helps prevent the virus and is given as part of a kitten’s initial vaccinations around eight weeks old.
A booster vaccination should also be given annually to maintain immunity. Unfortunately, the vaccine will not work on cats which have already been infected, so it’s important to book kittens in for vaccinations as soon as they’re old enough.
However, if your cat has never been vaccinated, it’s not too late - adult cats can be given their first vaccine at any age. Although it’s very effective, the vaccine cannot guarantee protection, so un-infected cats should not be allowed contact with cats which are FeLV-positive.
My cat has FeLV – what should I do?
If your cat has FeLV it’s important to avoid the spread of the virus by making sure they do not mix with FeLV-negative cats.
Do I need to keep my FeLV cat inside?
This normally means they need to be kept indoors, or in an escape-proof garden that cannot be accessed by other cats.
Cats with FeLV should keep up their annual vaccination boosters, as this will help protect them against other infections. Although the outlook for cats with FeLV is poor, your vet may be able to manage symptoms of secondary infections with antibiotics and other drugs.
Sadly, many affected cats have to be euthanised because they have a poor quality of life. Your vet will be best placed to talk you through what is best for your pet.
Knowing when to let go of a much-loved pet is difficult, and there are services like Cats Protection’s Paws to Listen grief support that can help.
Love cats? Check out our pets section for advice on cat care from How to take your cat to the vet without stress to how to stop them scratching furniture
Cats Protection is the UK’s largest cat charity - to find more tips from the charity about humane ways of keeping cats out of your garden, visit cats.org.uk
