Difference between Active and Passive Immunity
Immunity is the body’s ability to destroy foreign materials and pathogens in order to prevent further infection. The human body’s first line of defense against pathogens is through barriers such as skin, mucus layers, and saliva. This is known as innate immunity. The second line of defense is through phagocytes; this is again produced by innate immunity. The third line of defense is through adaptive immunity. Difference between Active and Passive Immunity
These are two types of adaptive immunity. An important difference between is that active immunity develops due to the production of antibodies in the body itself, while passive immunity develops by antibodies that are produced outside and then introduced into the body. In this article, let’s look at more differences between them.
Active Immunity vs Passive Immunity Difference between Active and Passive Immunity
Main differences: Difference between Active and Passive Immunity
Below are the important differences between these two concepts of the immune system:
| Active immunity | Passive immunity |
| Active immunity is usually permanent: it is produced by the host’s antibodies in response to direct contact with an antigen. | Passive immunity lasts for only a few weeks or months. It is produced by the introduction of antibodies from outside the host. |
| Produces an immune memory | Does not produce immune memory |
| When antigens enter the body, antibodies and other specialized lymphocytes are produced. | Antibodies are introduced from an external source. For example, a mother introduces antibodies to a fetus through the placenta and to a baby through breast milk. |
| No side effects | May cause reactions. |
| Immunity does not occur immediately | Immunity develops immediately |
General summary
- Active immunity is achieved through exposure to a pathogen. This leads to the production of antibodies in the body. Antigens present on the surface of pathogens act as markers that bind to antibodies.
- Passive immunity is acquired when antibodies are introduced into the body from an external source (usually through vaccines). Provides a quick response to infection.