Notes from NEET topper
Active vs. Passive Immunity: Active immunity is acquired when the body’s immune system responds to an antigen by producing antibodies or activating immune cells. This can occur naturally when a person becomes infected with a pathogen, but it is also achieved through vaccination, where a weakened or inactivated form of the pathogen is introduced to stimulate an immune response. Active immunity provides long-lasting protection because it results in the formation of memory cells that “remember” the pathogen.
Passive immunity, in contrast, involves the transfer of pre-formed antibodies or immune cells from one individual to another. This can happen naturally, such as when a mother passes antibodies to her baby through breast milk, or it can be artificially induced by administering specific antibodies or immune cells directly. Passive immunity provides immediate but temporary protection, as the recipient’s immune system is not actively involved in the process.
