Hello everyone.....
 My cat has recently turned 3 years old and is strictly an indoor kitty. 
He had all his kitten shots and is neutered. Last year at this time,
because I was taking him out of the country, he had all his shots
again, including a rabies shot ( required by U.S. immigration ).
My question is, does he need yearly boosters? I know he doesn't need a
rabies shot because he does not go outside nor is he exposed to any
other animals.My previous cat, who died at age 19, never had yearly
shots because I was in the belief that cats build up an immunity to
feline diseases after the original set of kitten immunizations.
Please help as I want to be sure I give my beloved cat the healthiest
and longest life possible.
I know that if I asked a veterinarian they would just say
yes....however, I prefer to see what others have to say.

Thanks.....

Steph,

Some vets are moving away from recommending yearly shots for indoor
cats. The shots themselves can cause medical problems (including
tumors) in some cats. Here's an excerpt from an interesting article:

"Our current recommendations are annual immunizations for the
respiratory pathogens (viruses and bacteria) in dogs and cats. These
are the 'Kennel Cough' agents in the dog and the 'Upper Respiratory
Agents' in the cat. The immunity generated by the mucosal cells, the
cells lining the airways, does not last a long time. Mucosal cells do
not create 'memory cells' which give the long lasting immunity. The
more 'whole body' pathogens such as Canine Distemper, Hepatitis, and
Parvovirus, and Feline Distemper, which is also a Parvovirus, create
memory cells.  Once produced, these memory cells give long term,
possibly life long immunity to these agents. For Canine Distemper,
Hepatitis, and Parvo Virus and Feline Distemper we recommend the pet
receive them in a series of shots when puppies and kittens, once as an
adult, that is one who is over one year of age, and then as
appropriate for each individual and their own circumstances. As a
geriatric patient their immune response fades along with their other
systems fading and they will need stimulus of their immune system by
vaccinations.

Rabies is an area that has its own legal issues to deal with besides
the medical issues. The first time a Rabies Vaccine is administered it
is medically documented and legally accepted as one-year protection. A
second Rabies Vaccination given one year later is medically documented
and legally accepted as three years protection. We recommend this
program for all dogs and for cats left alone outside the house. Indoor
cats, by their lifestyle, are not at risk for Rabies."


http://www.petresource.com/Articles%20of%20Interest/vaccinations_for_dogs_and_cats.htm