This is a summary of the article:
Feline Vaccination Guidelines, by James Richards, DVM, and Ilona Rodan, DVM, p 455-472
in Vol 31, No 3, May 2001, Veterinary Clinics of North America: Small Animal Practice
The development of the guidelines was based on the overall goals of vaccination. These are “to vaccinate the largest possible number of individuals in the population at risk, vaccinate each individual no more frequently than necessary, and vaccinate only against infectious agents to which individuals have a realistic risk of exposure and subsequent development of disease.” Kittens, which are more susceptible to severe infections, are the primary target and because of the maternal antibodies, they require a series of shots to develop proper immunization.
Use of polyvalent vaccines, that is, vaccines for more than one disease, is discouraged except for the 3 core vaccines (herpes, calici, and panleuk).
Feline Panleukopenia (FPV): Because the virus can remain in the environment for over a year and because it has a high mortality rate in young cats, vaccination is recommended for all cats. Maternal antibodies interfere with vaccination in kittens under 12 weeks. Most vaccinated animals are 100% protected, although intranasal vaccines may not give complete protection. There are studies showing the duration of immunity (DOI) is at least 7 years. The vaccine for FPV does protect cats against canine parvovirus-2b, which can infect cats. There are no associations with tumors. Kittens and pregnant queens should not be vaccinated with modified live vaccines because of neurological development problems.
Feline Herpes (FHV-1) and Feline Calicivirus (FCV): These two cause about 90% of respiratory problems in cats and are highly contagious. Both are self-limiting in adults, but can be fatal in kittens. Maternal antibodies interfere with vaccination in kittens under 12 weeks. DOI is at least 3 years. Vaccines reduce the severity of the disease, but do not prevent infection. Topical vaccines (intranasal or conjunctival) are useful for cats placed in situations with ongoing URIs such as shelters and can be given to kittens as young as 10 days. There are some reports of mild reactions, but no reports of sarcomas.
Rabies: Rabies vaccination is highly recommended for all cats and is required in some places. The adjuvanted vaccine [adjuvanted means a vaccine with something added to increase the immune response] is associated with vaccine-reactions, such as swellings and with sarcomas. When this was written, all rabies vaccines were adjuvanted, except for the recombinant form.
Feline Leukemia Virus (FeLV): Vaccination should be based on age (cats under 4 months are most at risk) and risk of exposure (outdoors or mixed -/+ households are most at risk). Vaccination is NOT recommended for older (> 5 months) cats with little exposure [indoor older cats]. Different brands of vaccine vary in their immune response – separation of infected cats is a better alternative to vaccination. The vaccines have been associated with fibrosarcomas. DOI is about 1 year, requiring annual booster shots.
Chlamydiosis: This bacteria causes conjunctivitis and respiratory problems, which respond well to antibiotics. As with herpes and calici, the vaccine only lessens the effects, but unlike them, there are frequent reactions to the vaccine. Because the reactions seem to outweigh the disease, vaccination is not recommended except where Chlamydia has been confirmed.
Feline Infectious Peritonitis (FIP): The vaccine has two major problems. First, the vaccine should not be given before 16 weeks of age, by which time most kittens are already infected with the coronavirus. Second, “there is no evidence that the vaccine induces clinically relevant protection” – in basic, it doesn’t work. Thus, it’s not recommended at all.
Dermatophytosis (Ringworm): The vaccine does lessen the duration of ringworm infection and perhaps reduces the spores produced, but will not prevent infection. DOI is unknown.
Bordetella bronchiseptica: This causes respiratory problems, can occur into upto 80% of cats from shelters and multi-cat homes, and is self-limiting [cats routinely recover without medication]. At the time of writing [late 2000], there were no independent studies on this vaccine for either effectiveness or DOI. It is only recommended for multiple cat environments like shelters, catteries, board facilities where Bordetella is known to exist.
Giardia: This is a protozoan which can cause acute gastric upset. The vaccine was not recommended for all cats as it was not proven effective in wide trials [as of 2000], but in licensing trials, the vaccine was shown to shorten the duration of diarrhea upon exposure and the length of cyst shedding. It should be considered for cats in areas with giardia exposure. DOI is 1 year or longer.
These guidelines were in 2001 very controversial as most vet schools were still teaching that vaccines had to be given annually to ensure immunity. Likewise the comment that multiple vaccines should not be given at once, except for the main 3 core vaccines, which would eliminate 5-in-1 shots.
The actual vaccine schedule given in this article was later adopted by the American Association of Feline Practitioners and is given below. Essentially, it is the same, only the timing of the kitten shots has changed and the deletion of vaccines which were deemed not necessary, such as ringworm.
Reading this article confirmed to me that my decisions regarding with respect to vaccinations are okay. I say okay because I can see there may be a slight potential for improvement. For most of my cats, I do not vaccinate at all. They are older, come from shelters which always do the core vaccines on intake. My cats are all indoors with no FeLV+ cats and no exposure to rabies. So there's little reason to vaccinate them.
Bodhi, my kitten, may need a booster for the 3-in-1 core vaccines because he is a 'baby' and because he goes to cat shows. Peaches I will have to think about since she goes to shows but she's older so I don't know. It's the 'high exposure, stressful situation' in the comments that bother me because of the cat shows. And Langston, who got his kitten shots at ~1.5 yrs, might benefit from a booster.