Do Cats Need a Leukemia Booster?

Cats should start getting vaccinations at an early age.
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When you adopt your first feline, the amount of paperwork that comes with her might seem overwhelming. She needs a certain diet, requires annual checkups and needs vaccinations. Feline leukemia is not cancer. It is a highly contagious virus, and fending against it requires an annual vaccine.

Feline Leukemia Details

Feline leukemia, or FeLV for short, is a virus that devastates the immune system of cats. Kitties infected with this heartbreaking illness often get sick from simple bacteria, viruses and fungi in their usual environment. Feline leukemia affects the blood system and often leads to various types of cancers. It it a highly communicable disease, but cats can transmit only the virus to one another, not to other species or humans. Infected felines get other kitties sick by such means as sharing the litter box, eating from the same dish or biting.

When to Vaccinate

Before your cuddly companion gets her initial feline leukemia vaccine, she'll have to have her blood screened to ensure she is not already sick. Once your veterinarian confirms a negative reading, little Fifi will undergo a series of feline leukemia vaccines and boosters. Starting at 8 to 10 weeks of age, your kitten should get her first feline leukemia vaccine. After the initial vaccine, she'll need a booster three to four weeks later, says Dr. Debra Primovic, a veterinarian and managing editor for One year after the second booster, Fifi will need one more booster shot. From that point, she'll need an annual feline leukemia vaccination.

First Time Vaccines

If you're adopting a stray cat or feline with no history of vaccinations, the process is a little different. Your vet will first check your new addition for feline leukemia; upon a negative test result, she'll administer two doses of the vaccine. Three weeks later, your fuzzy friend will require another two doses, according to the Arizona Humane Society. From that point, you'll have to vaccinate your new companion against feline leukemia only one time per year.


Feline leukemia vaccinations come in traditional needle forms or less invasive types that transmit the vaccine directly through your fuzzy pal's skin. Both types have similar recommendations, as far as frequency, but your veterinarian may prefer one type over the other. Vaccines do not 100 percent guarantee your cat won't get feline leukemia. However, the feline leukemia vaccine can help build Fifi's immune system against the virus, drastically decreasing her odds of developing the disease. The vaccine is especially important for kitties that play outdoors, since they may come into contact with infected felines.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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