Vaccines are usually developed for diseases that are debilitating or life-threatening and easily spread. They are not available for all infectious diseases, although vaccines should protect against some severe infectious diseases commonly found in felines.
The first vaccinations should be given to kittens from around eight to nine weeks of age. This timing is important - too early and the antibodies they receive from their mother will interfere with the immune response to the vaccine, preventing it from working properly. Too late and kittens will be left susceptible to infection. Two vaccines are usually needed - three to four weeks apart. Giving vaccines twice ensures a satisfactory level of immunity. A booster vaccine should be given one year later to keep immunity levels high. Further needs should be discussed with your vet.
Vaccination has greatly reduced the incidence of life-threatening infectious diseases within the cat population. Whether or not your cat needs to be vaccinated will depend on its lifestyle and risk of infection, so make sure you talk to your vet.
Cats with FIV have a weakened or suppressed immune system and may be at greater risk of developing other infections if they are exposed to them. FIV positive cats can be vaccinated to offer some protection. Speak to your vet for more information.