A single vaccine protects dogs from parvovirus, distemper and canine adenovirus and the series for puppies should start at six to eight weeks old, says AVMA President Dr. Lori Teller, and spring is a good time to check that animals are up to date on this and other preventive care. For animals adopted as adults, Dr. Teller recommends owners visit their veterinarians as soon as possible so that their dog can receive any missing vaccinations as part of a preventive care regimen that should also include flea, tick and heartworm preventives year-round.