According to the [[Centers for Disease Control and Prevention]]'s Vaccine Glossary, '''Active active immunity''' is "the production of antibodies against a specific [[disease]] by the [[immune system]]. Active immunity can be acquired in two ways, either by contracting the disease or through [[vaccination]].
Active immunity is usually permanent, meaning an individual is protected from the disease for the duration of their lives."<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#a</ref>