Do Adult Cats That Have Never Been Vaccinated Still Need a Series of Vaccines?

"Are you sure I really need those shots?"
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It's common knowledge that kittens need a series of shots to protect them from common diseases, but it’s not so clear what to do when you rescue a kitty who’s never been vaccinated. While adult cats do require multiple shots, their needs are different from the little guys.

Basic Vaccinations

Cats are typically vaccinated against several common diseases, such as feline distemper, also known as panleukopenia, and various upper respiratory infections including chlamydia and rhinotracheitis. Kittens usually get the FVRCP shot to protect them against feline viral rhinotracheitis, calicivirus and panleukopenia, or they’re given the RCCP injection, which covers rhinotracheitis, calicivirus, chlamydia and panleukopenia. Depending on your cat’s situation and the diseases that are prevalent in your area, your vet may also recommend other shots for your pal, such as the feline leukemia shot or a vaccination against feline infectious peritonitis.


When a kitten is born, the first milk he gets from his mother contains antibodies that give him immunity to diseases that might otherwise kill him. This protection lasts for an indefinite period of time, but begins to wear off as the kitten gets older, and by the time he’s 12 to 14 weeks old his immunity is typically gone. Since a vaccination won’t do a kitten any good as long as his mother’s immunity is still protecting him, a kitten gets a series of shots two to four weeks apart to make sure he’s covered when he needs it.


If you have an adult kitty who’s never had a shot before, you can be sure that he’s not carrying around any of mom’s antibodies. That means that the timing of his shots isn’t an issue, so you can give him his first shot the day you bring him home. While he doesn’t need a whole series of shots to make sure that he’s protected, a follow-up booster about three to four weeks after the first shot will help to make sure your kitty’s immunity levels are high enough to protect him in case of exposure to disease.


No matter how old your pet is when he starts getting his shots, he’ll need periodic boosters once the initial series has been completed. How often he needs the shots depends on some variable factors, including the type of vaccine your vet uses and your kitty’s lifestyle. Cats who roam freely outdoors may need a booster shot every year, while kitties who live in the house full time may only have to get an update every three years. Your vet can give you the details about what your buddy needs and when he needs it.

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