Introduction
Most veterinarians agree that all cats should be vaccinated against those diseases that are widespread, cause serious illness, and/or are highly contagious (core vaccines). In addition, other vaccines may be recommended based on the risk they pose to individual cats (non-core vaccines). Note that may pet owners believe vaccines produce 100% protection in all cats. This is not true. Some vaccines will protect most cats, but others may only reduce the severity of clinical signs.
Core Vaccines for Cats
Feline Panleukopenia (parvovirus, distemper)
Panleukopenia is a potentially fatal viral disease that causes vomiting, diarrhea, severe dehydration, fever, and sudden death. Kittens born to infected queens may suffer permanent brain damage. Younger cats appear more susceptible to parvovirus. This disease is easily prevented through vaccination—vaccination is considered highly effective.
Feline Rhinotracheitis (Herpes virus Type 1) and Calicivirus
These organisms infect the airways of cats, causing runny eyes and nose, sneezing, mouth ulcers and sometimes poor appetite. Although vaccines may not prevent infection altogether, they often greatly reduce the severity of the disease. Spread is usually by cat-to-cat contact, aerosols from sneezing cats and infected surfaces. High risk kittens may be vaccinated early for these agents, and all cats should receive the vaccinations for these infections. Mild clinical signs may be noted post-vaccination.
Rabies
All mammals, including humans, are at risk of contracting rabies, which is almost invariably fatal. Rabid pets may display a "dumb" form which is characterized by listlessness, weakness and paralysis, or the "furious" form of rabies characterized by abnormal aggression. Newer vaccines have safe formulations, and are specially designed for felines. Even indoor cats should receive this vaccine as they can sneak out, and wildlife may unexpectedly enter the home.