Passive immunity is the short-term protection that occurs when ready-made antibodies are transferred from another person or animal to an individual. It provides immediate defense against infection but does not create memory cells, so the protection lasts only for a limited time. Examples include antibodies passed from mother to baby or antiserum injections like tetanus or rabies immunoglobulin.

1. Title: Passive Immunity
Name: Sadia Liaquat
Arid No: 23-Arid-1912
Rechecked By: Mamoona Liaquat
Arid No: 23-Arid-1903

3. Passive Immunity
 In passive immunity, antibodies from one individual are passed into
another individual.
 They give immediate protection, unlike active immunity which takes a
few days or weeks to build up.
 However, it only provides protection for a few weeks, as antibodies
are broken down by the body’s natural processes.
 Their number slowly falls, and protection is lost — therefore,
immunity is temporary.

4. Natural Passive Immunity (Introduction)
 Passive immunity may be gained naturally.
For example, antibodies from a mother can cross the placenta and enter
her foetus. In this way, they provide protection for the baby until its own
immune system becomes fully functional.

5. Natural Passive Immunity (Continued)
 Passive immunity may also be provided by colostrum, the first
secretion of the mammary glands.
 The baby absorbs the antibodies through its gut.
 These antibodies mainly include IgA (Immunoglobulin A).

6. Artificial Passive Immunity (Introduction)
 In artificial passive immunity, antibodies formed in one individual are
extracted and then injected into another individual.
 The recipient may or may not belong to the same species.
 This method provides immediate protection if a person has been, or is
likely to be, exposed to a particular disease.

7. Artificial Passive Immunity (Examples)
 Specific antibodies used for combating tetanus and diphtheria were
once cultured in horses and injected into humans.
 Now, only antibodies of human origin are used.
 Antibodies against rabies and some snake venoms are also available.
 Additionally, antibodies against the human Rhesus blood group antigen
are used for protection.

8. Thank You!