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Related to active immunity: passive immunity, natural immunity, artificial passive immunity, artificial active immunity, artificial immunity
resistance resulting from previous exposure of an individual in question to an infectious agent or antigen; it may be active and specific, as a result of naturally acquired (apparent or inapparent) infection or intentional vaccination (artificial active immunity); or it may be passive, being acquired through transfer of antibodies from another person or from an animal, either naturally, as from mother to fetus, or by intentional inoculation (artificial passive immunity).
Immunity resulting from the development of antibodies in response to the presence of an antigen, as from vaccination or exposure to an infectious disease.
Active ImmunityThe natural immune response to an antigen by infectious exposure or inoculation, resulting in the formation of specific antibodies and protection from subsequent infection by the same pathogen.
ac·quired im·mu·ni·ty(ă-kwīrd' i-myū'ni-tē)
Resistance resulting from previous exposure of the individual in question to an infectious agent or antigen; it may be active, as a result of naturally acquired infection or vaccination; or passive, being acquired from transfer of antibodies from another person or from an animal, either from mother to fetus or by inoculation.