noun[mass noun] Physiology
The immunity which results from the production of antibodies by the immune system in response to the presence of an antigen. Compare with passive immunity.
More example sentences
- Vaccination provides active immunity because our immune systems have had the time to recognize the invading germ and then to begin production of specific antibodies for the germ.
- This vaccine is designed to stimulate both antibody and T-cell responses and to generate active immunity at mucosal surfaces, the first site of viral assault during most HIV infections.
- Researchers expended considerable effort to develop methods of active immunity to prevent scarlet fever, as well as methods of passive immunity to treat scarlet fever.
Definition of active immunity in:
- The US English dictionary