Feline lukemia

How often do cats need a feline lukemia vaccine? I have heard they only need one in a lifetime and some say every year.

[Aleda M Cheng, D.V.M., C.V.A]

The best way to check if your cat's feline leukemia vaccine is still working is to have your veterinarian perform a feline leukemia vaccine titer.  If the level of the titer is adequate your cat does not need a vaccine or booster.  A titer can be performed yearly, or every other year.  If the titer always tests as adequate than your cat does not need to be vaccinated, unless you feel more comfortable with the vaccine.  Titers can be done for all vaccines not just feline leukemia.  Titers are becoming a more valuable tool in veterinary medicine but they are usually more expensive than vaccines.