Vaccinations have greatly reduced the incidence of a number of infectious diseases over the past few decades. They work by introducing either a modified live vaccine which contains viruses that have been altered so that they are no longer able to cause disease, or a killed disease-causing organism (virus or bacteria). This, in turn, stimulates the immune system, making it better able to defend against the disease should it be exposed to the cat at a future date.
There are two kinds of vaccinations core and non-core vaccines. Their usage may vary depending on where you live and local regulations.
The core vaccination is known as F3 or FCRVP, which stands for Feline Viral Rhinotracheitis Calicivirus and Panleukopenia. Core vaccines are vaccinations which should be given to all cats regardless of location.
Diseases covered by the core vaccinations are:
Feline viral rhinotracheitis (also known as feline herpes virus)
Non-core vaccinations are vaccinations which may not be necessary for all cats depending on your cat's individual circumstances as well as local laws. One example is the rabies vaccine for cats living in Australia, as we don't have rabies in Australia, the vaccine isn't required. None core vaccines include:
Feline infectious peritonitis
* The rabies vaccine is compulsory in most states of the United States of America.
Side effects from vaccinations occur between 30-50 cats per every 10,000 cats vaccinated, and most of those reactions are non-serious. 
Some kittens may be a little lethargic or listless after a vaccination. This generally passes within 24 hours.
Soreness may occur at the spot the vaccine was administered. This should be gone within a day or two.
A small, painless lump may occur at the spot of the vaccine. This will generally go away within a few weeks, but it is important to keep an eye on the lump. If it doesn't go away, or if it increases in size, seek veterinary attention.
Hair loss at the site of injection may occur in some cases. This will grow back in time.
Intranasal administration of vaccines can cause mild sneezing and discharge.
Severe allergic or anaphylactic reactions to the vaccine can occur in very rare cases.
Vaccine-associated sarcomas (VAS), which are a type of cancer that results from vaccinations can develop, especially rabies and feline leukemia vaccines. The occurrence of VAS is estimated to be 1 to 10 per 1,000 cats vaccinated.
In some cases, the vaccine may not be effective, which is known as 'vaccine failure'. There are a number of causes of this including improper transport or storage, inadequate immune response to the vaccine, maternal antibodies inactivating the vaccination.
Do bear in mind that while there is a small chance of side effects occurring, vaccines have prevented millions of cats developing life-threatening diseases and saved lives.
Most vaccines are administered via injection under the skin (usually at the scruff of the neck), there may be a little discomfort, but it is minor and only lasts a second or two. Some vaccines can be given intranasally.
Some veterinarians prefer to administer vaccinations in the legs, this is due to the slight risk of vaccine-associated sarcoma (VAS). The theory is if the cat does develop VAS, it is easier to amputate the affected limb, giving the cat a better chance of survival. If this is the case, the FeLV vaccine will be injected under the skin on the left rear leg and the rabies vaccine will be injected under the skin of the right rear leg.
The average cost of the core F3 vaccination is between $60-$75 dollars. If you have pet insurance check to see if you are eligible for a rebate for the cost.
Yes, the most of the diseases vaccinated against are deadly to cats.
The kitten will have protective antibodies (maternally derived antibodies, or MDA) in his system which he received from his mother both in-utero and via the mother's colostrum (the first milk she produces). This is known as maternal immunity and serves to protect young kittens from pathogens while their immune system is still immature.
Over time this maternal immunity diminishes, which then makes the kitten vulnerable to many pathogenic diseases. It is believed that this starts to occur around the eighth week of age which is when the kitten's first vaccination is scheduled. In some kittens, maternal immunity may last longer, in which case the vaccine will be inactivated by the antibodies in the kitten's system. Therefore to ensure all kittens are protected, a series of THREE vaccines are scheduled at 8, 12 and 16 weeks of age to cover all kittens, regardless of when their maternal immunity starts to wane.
Indoor cats still need to be vaccinated as they are still at risk of pathogens. He may escape (it can happen despite our best intentions) and be exposed either via a non-vaccinated cat or if he is handed into a shelter, he could be exposed during a trip to the veterinarian, or if you adopt a new cat who could potentially bring in an infection.
Core vaccines F3/FCRVP - All cats
|F3 (1st shot)||6-8 weeks|
|F3 (2nd shot)||12-14 weeks|
|F3 (3rd shot)||16-18 weeks|
|F3 (booster shot)||12 months and then every 1-3 years|
* Many veterinarians are now moving away from annual booster shots for core vaccinations and are recommending tri-annual shots for low-risk cats. This is backed by the American Veterinary Medical Association and the Australian Veterinary Association.
Non-core vaccines - High-risk cats or compulsory vaccinations in certain countries or states
|Rabies (one shot)||12 weeks|
|Rabies (booster)||12 months|
|FeLV (1st shot)||8 weeks|
|FeLV (2nd shot)||12 weeks|
|FeLV booster||Every 12 months|
|FIV (1st shot)||8 weeks|
|FIV (2nd shot)||10 weeks|
|FIV (3rd shot)||12 weeks|
|FIV (booster shot)||Every 12 months|
|Chlamydia (1st shot)||9 weeks|
|Chlamydia (2nd shot)||11-13 weeks|
|Chlamydia (booster shot)||12 months and then every 1 year|
|Bordetella booster||Every 12 months|
|Feline infectious peritonitis||16 weeks|
|Feline infectious peritonitis||19-20 weeks|
|Feline infectious peritonitis (booster shot)||Every 12 months|
That is up to you, the recommendation is tri-annually, but if you would prefer not to do this, it is highly recommended you ask your veterinarian to perform a titre test. This tests the levels of antibodies in your cat's blood which can indicate if he is still protected against common pathogens. The cost of a titre test is similar to the cost of routine vaccinations.
Even if you decide not to vaccinate your cat as per the recommended guidelines, it is still necessary to have an annual 'wellness check' to evaluate your cat's overall health.
Bear in mind that if your cat isn't up to date on his vaccinations he may not be permitted into boarding catteries.
Recommendations are that an adult cat with no prior history should receive two F3 vaccinations spaced four weeks apart followed by a booster shot at 12 months and then every 3 years for low-risk cats.
Vaccinating an immunocompromised cat
Speak to your veterinarian about vaccinating an immunocompromised cat, such as one with feline immunodeficiency virus. He may recommend only using killed vaccines.
Where possible it is always safer to avoid vaccinating a pregnant cat, but if she has had no vaccinations at all speak to your veterinarian about a possible safe vaccination protocol using a killed vaccine.
Live vaccinations should be avoided as they can cross the placenta and cause deformities in the developing kittens. Always speak to your veterinarian about any medications or vaccines for your pregnant cat, in many cases, it is safer to wait until the cat has delivered and weaned her kittens.
If you are planning to fly your cat to another country it is essential you check to see what vaccinations are necessary as this can vary from country to country. Most cats will be issued with a 'pet passport' which will show the cat is up to date on his vaccinations. You will need to find out what vaccinations your cat will require well ahead of time. For example in many countries, the rabies vaccination must have been administered at least 30 days prior to travel. The best place to start is with your veterinarian who should be able to advise you on what steps you need to take to ensure your cat is adequately vaccinated.