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Immunity is the body's protection against a [[disease]]. There are two types of immunity, passive and active.  

'''Immunity''' is the body's protection against a [[disease]]. There are two types of immunity, passive and active.  

Immunity is indicated by the presence of [[antibodies]] in the blood and can usually be determined with a laboratory test.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#i</ref>

Immunity is indicated by the presence of [[antibodies]] in the blood and can usually be determined with a laboratory test.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#i</ref>