To prevent canine distemper, puppies should begin vaccination at 6-8 weeks of age and then continue getting the “booster shot” every 2-4 weeks until they are 16 weeks of age. Without the full series of shots, the vaccination does not provide protection against the virus. Since puppies are typically sold at the age of 8-10 weeks, they typically receive the first shot while still with their breeder, but the new owner often does not finish the series.