Vaccinations are given to cats in order to help their immune system fight off disease. If the mother was properly vaccinated prior to pregnancy, most kittens will receive protective antibodies through nursing, primarily during the first twenty-four hours of life. These antibodies will generally last for eight weeks, and then kittens must be immunized with injections. Kittens are generally given a series of vaccinations every three weeks until they reach about sixteen weeks old. At this age, cats are only required to be vaccinated once a year. There are six feline diseases commonly vaccinated against. Three of them are given in one injection, and both the feline leukemia and the rabies vaccine are administered as separate injections. The final vaccine is administered in drops through the nose. Cats should receive boosters on all vaccines, even rabies, on a yearly basis. For more information on cat vaccinations, consult a veterinarian in your area.