Puppies and kittens need a series of vaccinations given 3 - 4 weeks apart, between the ages of 8 and 16 weeks. (wellpethumane.com)
While vaccination for certain core viruses is certainly important, too many vaccinations given too frequently may lead to the development of chronic disease and even cancer in some sensitive pets. (1800petmeds.com)
Although dogs do not have full immunity until after the booster has been administered, it is beneficial to at least have one vaccination given before exposure to other dogs. (berkeleydogandcat.com)