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Inactivated vaccines are contrasted with Attenuated vaccines, or "live" vaccines. Examples of "live" (i.e. attenuated) vaccines include:
The virus particles are destroyed and cannot replicate, but the virus capsid proteins are intact enough to be recognized by the immune system and evoke a response. When manufactured correctly, the vaccine is not infectious, but improper inactivation can result in intact and infectious particles. Since the properly produced vaccine does not reproduce, booster shots are required periodically to reinforce the immune response.