Cat leukaemia

Feline leukaemia (FeLV) is a retrovirus, belonging to the same group of viruses as HIV. It is much less common in cats nowadays than it used to be, with less than 1% of healthy cats infected.

What is feline leukaemia?

Feline leukaemia (FeLV) is a retrovirus, belonging to the same group of viruses as HIV, however it can’t infect humans.

It is much less common in cats nowadays than it used to be, with less than 1% of healthy cats infected. This is due to widespread and effective vaccinations amongst kittens and cats since the 1990s.

What happens if my cat or kitten gets feline leukaemia?

Feline leukaemia suppresses the immune system and causes a slow infection, leaving the infected cat highly vulnerable to other diseases, including:

• Cancers
• Inflammation of different body organs
• Reproductive problems

In kittens it can cause a slow and gradual decline, which when left untreated will lead to death.

How is feline leukaemia spread?

It is passed between cats in saliva when they groom one another, share food bowls and are generally close to each other. It can also pass in other body secretions, blood and milk.

It is a virus that can hide inside the cells of the kitten or cat’s body – this is termed latency. It inserts its DNA into the cat’s DNA, with the virus able to wake up and cause a disease long after the initial infection.

How long could feline leukaemia last for in cats?

The course of feline leukaemia usually lasts up to three years, although in many cases the cat will pass away sooner.

Is it possible to vaccinate against feline leukaemia?

Fortunately, vaccination is available which helps prevent persistent infection and fatal disease.

The feline leukaemia vaccine is one of the core vaccinations, meaning it is mandatory for all cats and kittens. You should speak to your vet to put an appropriate vaccination programme in place for your kitten.

When's the best time for my kitten to be vaccinated?

The ideal age for your kitten to have its first vaccination is at eight weeks, followed by a second three to five weeks later. This will be for the core vaccines that protect the kitten against the most common and high-risk diseases. They include:

• Cat flu – both feline herpesvirus (fHV) and feline calicivirus (FCV)
• Feline panleukopenia virus (FPV)
• Feline leukaemia virus (FeLV)

Your vet will also advise you on any other recommended vaccines for your kitten depending on their lifestyle, specifically if they’ll be going outdoors or not, or whether they’ll be in contact with other cats.

Does the vaccine for feline leukaemia need a booster injection?

Yes, as with the other core vaccinations, your vet will administer a first booster injection for feline leukaemia between 12 and 16 weeks of age.

As soon as your kitten reaches one year old, they’ll need their first annual booster which will then be followed up every year. It's important to contact your local vet if you need any more information or specialist advice.