Kitten Vaccinations Pros & Cons


I have heard that vaccines can have serious side effects and I am not sure if I should have my kitten vaccinated?  What are the pros and the cons?


Discontinuing “core” vaccines due to their potential side effects is a bad idea.  We would lose a large number of our cat and dog population without the “core” vaccines that are currently widely used.  Many fatal diseases, such as parvo, are no longer regularly seen thanks to the protection that vaccines offer.

In recent years, we have learned that certain vaccines do come with some possible long-term side effects that are more serious than the short term “vaccine reaction”.  Among these, vaccine injection site sarcomas (a type of cancer that occurs at a previous vaccine injection site) seem to be an area of concern for many cat owners.  Efforts have been made to determine exactly which vaccines cause these side effects in a very small percentage of cats (about 1-2 cases per 10,000 vaccinated cats) and why.  There are still many unanswered questions, but the most current thinking is that the risks of vaccine associated sarcomas can be reduced by implementing the following protocols:

  1. Avoid vaccines that have been shown to be minimally effective;
  2. Avoid vaccinating for diseases to which there is no exposure risk;
  3.  Adopt longer inter-vaccine intervals for low-risk animals;
  4.  Use newly developed, safer vaccines;
  5. Run antibody titers for certain diseases (to test if the animal is still protected from previous vaccination) and vaccinate only if a protective titer can’t be demonstrated; and
  6. Administer the vaccine injection away from the body trunk (allowing for a better surgical outcome in the event that a sarcoma should arise).

The bottom line is that certain vaccines are vital to protect both your pet as well as the pet community as a whole.  Without these “core” protective vaccines, your pet is at a much higher risk of deadly disease than the relatively low risk that a particular vaccine may cause.  You and your vet can further minimize the low risk of side effects by employing the practices listed above.  For more information on the pros and cons of individual vaccines as well as the UC Davis protocols, visit


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Max Conn, DVM is the owner of Cat & Exotic Care of the CentralCoast, a full service veterinary hospital dedicated to the special needs of cats, birds, reptiles and small mammals.  Cat & Exotic Care is located in PismoCoastPlaza, 565 Five Cities Drive, 805-773-0228.  More information can be found at


Disclaimer: The informational handouts and website links above are for informational purposes only, they are not intended to replace veterinary care.