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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 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>

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>