FIP stands for feline infectious peritonitis, a viral disease that's almost always fatal though not common. Cats most at risk are those under 2 years of age and those who live with many other cats.
The FIP shot is a live vaccine made from a temperature-sensitive mutant FIP strain. The idea is that you spray a small amount of the virus into the cat's nose and the virus replicates but only at cool temperatures. Once the virus moves deep into the cat's body, the heat kills it. Unfortunately, this may not be sufficient to induce immunity. While there's no evidence that the vaccine is dangerous, there is little evidence that it's effective.
The feline leukemia (FeLV) vaccination got a bad rap initially because it was frequently ineffective and many breeders believed it to increase the risk of FIP. Its efficacy seems to have improved, though some experts argue that the better statistics largely reflect the way the vaccine is tested. Mature cats are already somewhat immune to feline leukemia, so if efficacy is surmised from an adult population, the vaccine will appear to offer powerful protection.
The latest and greatest vaccine is for the bacterial illness, bordetellosis. The rage for this vaccination has been fueled by studies, many from Great Britain, that cats in shelters often develop coughing and other symptoms of respiratory tract disease from the bacterium Bordetella bronchiseptica, which causes kennel cough in dogs. (House cats occasionally pick it up too.)
Bordetellosis in kittens can lead to life-threatening pneumonia. But, no one really knows how often bordetellosis is a problem in mature cats or whether the new vaccine would do anything to address it. This vaccine is most appropriate for a cat who's about to be boarded or bred at a cattery. For the average pet, who knows?
When and where your cat gets a vaccine will depend on what your veterinarian advises based on his or her experience as well as on the recommendations of groups such as the American Veterinary Medical Association and the American Association of Feline Practitioners.
In general, you may find the first FVRCP vaccine is given at 6 to 8 weeks of life (definitely at 6 weeks if the kitten is not with its mother), and repeated every two to four weeks until the cat is 16 weeks old. After that, the FVRCP shot may generally be given annually, but occasionally there are reasons to deviate from this schedule (see the next two sections below).
If the cat is already an adult when the vaccination program begins, standard practice is to give two vaccines one month apart and then revaccinate annually. Most vaccines are given either under the skin or in the muscle. A few are delivered in the nose.
Protocols for rabies vaccines are thoroughly spelled out in regulations set by a state's veterinary medical or public health board. Specifications include which brand to give at what age and what site (for example, in the muscle). Generally you start when the cat is 16 weeks or 6 months old, repeat in one year, and then move to a schedule of once a year or once every three years, depending on state law.
Owners are, of course, concerned about the possible side effects of vaccination, which include:
A fibrosarcoma is a cancerous tumor that cats can develop. In the recent past, experts noted that these growths had become much more common between cats' shoulder blades, the site where most practitioners gave subcutaneous vaccines. In an attempt to solve the problem, the recommendation was made to give more vaccines intramuscularly. Yet this resulted in an increase in fibrosarcomas at those sites as well.
Experts don't know exactly why vaccines sometimes set off fibrosarcoma. It may be a result of trauma at the injection site, or it may be that the adjuvant (a chemical added to make a vaccine more potent) somehow triggers the cancer.
An infection can develop if a vaccine is modified-live (meaning living strains of virus are used). The medical principle is that the cat will experience a low-grade infection that will make his body develop immunity to more virulent strains of the disease. Such vaccines are used because killed vaccines are supposedly less effective.
Does Your Cat Need Every Vaccine?
Even veterinarians have some trouble deciding which cats should get which vaccinations. The vaccine for panleukopenia, an often fatal disease, protects most cats, so that's an easy call. Some practitioners believe that feline herpes and feline caliciviral (FCV) infections would be much more severe if vaccines weren't widely administered. In addition, a number of people credit feline leukemia vaccination with dramatically reducing incidence of the disease, but testing and euthanasia have also contributed to this trend.
As a result of the confusion, some experts have started to recommend giving fewer vaccines - moving to a schedule of every three years, for example. Ask your vet about each vaccine's risks and benefits.
Even if you and your vet decide on a vaccination schedule that has your cat going two or three years in between shots, don't assume that your cat can do without a wellness checkup every 12 months. It is absolutely essential that every cat receive a complete physical exam every year. The risk of annual vaccines is negligible compared with the risk of treatable problems going undetected.
Sometimes it takes an emphasis on vaccines to encourage owners to bring their cats in for regular physicals. The benefits of the yearly physical examination greatly outweigh the slight chance of a vaccine reaction in most circumstances.