Changes

Waning immunity is the loss of protective [[antibodies]] over time.  

'''Waning immunity''' describes the loss of protective [[antibodies]] over time. Infections and vaccines induce an immune reaction, part of which is a memory function, mostly contained in Memory B-Cells.  When reexposed to the antigen in question, the B-Cells begin to reproduce and make antibodies to the antigen.  In some cases, the memory function is more effective than in others.  For instance, the tetanus vaccine's effectiveness wanes over time.  Immunity to chickenpox acquired via natural infection probably lasts a lifetime, however this is less clear, as the virus persists in nerve roots indefinitely which may help maintain an immune response.

 

Vaccines often have waning effect against antibodies which can evolve and develop the ability to resist them.

[[Category:Medicine]]

[[Category:Medicine]]