Feline Leukemia Vaccine -
Prevention of Cat Leukemia

The feline leukemia vaccine offers protection (as opposed to cure) against cat leukemia.

The vaccine isn't 100% effective, but a cat who's had it stands a much better chance of avoiding feline leukemia than one who hasn't.

Feline leukemia is the biggest killer of domestic cats after road accidents.

It's caused by a virus which attacks the cat's white blood cells and reduces his ability to fight infections.

As the disease progresses, the cat gets more and more infections as his immune system weakens. It also causes some cats to develop cancer.

This page answers some of the most commonly asked questions about the vaccine.


Feline Leukemia Vaccine - Questions and Answers

1) Does the vaccine cure leukemia?

No. It builds up the cat's resistance to the feline leukemia virus (FeLV) so if he is infected after he's had the vaccine, he can fight the virus much better and hopefully get rid of it completely.


2) How effective is the vaccine?

This is a really difficult question to answer, because it depends on many factors such as the overall health of the cat, his / her age and the level of exposure to the virus.

The general consensus seems to be that it's about 70 - 80% effective. In other words, if 10 cats who have the vaccine are then exposed to the virus, 7 to 8 of them will successfully get rid of it.


3) If my cat doesn't have the vaccine what are the chances of him getting cat leukemia?

Again, this is a difficult question because it depends on a number of factors. But it is known that the chances of non-vaccinated cats getting leukemia after exposure to the virus are considerably higher than cats that have been vaccinated.


4) Is the vaccine expensive?

Not in comparison to treating a cat for multiple health problems, infections and / or cancer if he gets leukemia.

Prices do vary between vets, so it's worth shopping around. The average price is probably about $20 (US Dollars).


5) How often will my cat need to be vaccinated?

Kittens are usually vaccinated between 9 and 12 weeks of age, with a booster 4 weeks later. Thereafter, an annual booster only is needed.


6) Are there any cats that don't need the feline leukemia vaccine?

If your cat is a full-time indoor kitty with no means of escape, and he's not exposed to any other cats that go out, his chances of getting leukemia are tiny. In these circumstances, I'd question the need to give him the vaccine.

In all other cases, the vaccine, I believe, should be given.


7) Are there any nasty side effects of the vaccine?

Any vaccine can have nasty side effects if the cat has a bad reaction to it. Same applies to humans! But really bad side effects are very rare.

A small percentage of cats may be a bit off color for a day or two afterwards. This temporary glitch is far more preferable than the cat having to cope with FeLV and all its associated problems.

A very small number of cats (estimated one or two in 10,000) develop a type of skin cancer called sarcoma at the vaccination site. This puts some owners off the vaccine, but overall, the chances of a non-vaccinated cat dying from cat leukemia-related problems are far higher than a vaccinated one developing sarcoma.


8) Can my cat get leukemia from the vaccine?

No. The feline leukemia vaccine is made in such a way that it can't cause the actual disease.


Other pages you may find useful:

Cat Leukemia - Frequently Asked Questions
Feline Leukemia Symptoms
Feline Leukemia Test
Feline Leukemia Treatment



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