Types of Acquired Immunity
I. Naturally Acquired Immunity: Obtained in the course of daily life.
A. Acquired Active Immunity:
Antigens or pathogens enter body naturally.
Body generates an immune response to antigens.
Immunity may be lifelong (chickenpox or mumps) or temporary (influenza or intestinal infections).
B.Acquired Passive Immunity:
Antibodies pass from mother to fetus via placenta or breast feeding (colostrum).
No immune response to antigens.
Immunity is usually short-lived (weeks to months).
Protection until child’s immune system develops
II.Artificially Acquired Immunity: Obtained by receiving a vaccine or immune serum.
A.Artificially Acquired Active Immunity:
Antigens are introduced in vaccines (immunization).
Body generates an immune response to antigens.
Immunity can be lifelong (oral polio vaccine) or temporary
(tetanus toxoid).
B.Acquired Passive Immunity:
Preformed antibodies (antiserum) are introduced into body by injection.
Snake antivenom injection from horses or rabbits.
Immunity is short lived (half life three weeks).
Host immune system does not respond to antigens.