CAN I KNOW ABOUT THE DIFFERENT TYPES OF IMMUNITY?
| Active immunity | Passive immunity |
| Natural active immunity: It is the kind of immunity which is obtained as a result of an infection. The body manufactures its own antibodies when exposed to an infectious agent. Because memory cells, produced on exposure to the first infection, are able to stimulate the production of massive quantities of antibody when exposed to the same antigen again. | In passive immunity antibody 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. Natural passive immunity: Passive immunity can be gained naturally. For example, antibodies from a mother can cross the placenta and enter her fetus. In this way it provides protection for the baby until its own immune system is fully functional. Passive immunity may also be provided by colostrum, the first secretion of the mammary glands. |
| Artificial active immunity: This is achieved by injecting small amounts of antigens, called the vaccines, into the body of an individual. The process is called vaccination. | Artificial passive immunity: Here antibodies which have been formed in one individual are extracted and then injected into the blood of another individual which may or may not be of the same species. They can be used for immediate protection if a person has been, or is likely to be exposed to a particular disease. Only antibodies of human origin are now used for humans. Antibodies against rabies and some snake venoms are also available. |
Innate immunity- Immunity present at the time of birth.