Active immunity is when your body develops resistance to a disease after being exposed to it, which triggers the production of antibodies. One example of active immunity is a person's resistance to strep throat due to a previous infection.
Understanding Active Immunity
Active immunity means that your body is actively involved in producing its own protection through antibodies. These antibodies are proteins that fight off invaders, like bacteria or viruses. This is different from passive immunity, where your body receives antibodies from an external source.
Examples of Active Immunity
According to the provided information, active immunity can develop in these ways:
- Natural Infection: When someone gets sick with an infection, their body recognizes the invader and starts to produce antibodies. For example, if someone has had strep throat, their body develops antibodies that make them less likely to get sick from the same bacteria again.
- Vaccination: Vaccines introduce weakened or dead forms of a pathogen to the body, which stimulates antibody production without causing illness. The polio vaccine is an example where your body develops antibodies to polio.
Key Differences: Active vs. Passive Immunity
| Feature | Active Immunity | Passive Immunity |
|---|---|---|
| Antibody Source | Body makes its own antibodies | Antibodies come from an external source |
| Duration | Generally long-lasting | Generally short-lived |
| Examples | Strep throat after a previous infection, polio vaccine | Antibodies from mother to baby via breastmilk or placenta |
How Active Immunity Works:
- Exposure: Your body encounters a pathogen.
- Recognition: Your immune system recognizes the pathogen as a threat.
- Antibody Production: B cells produce specific antibodies to fight the pathogen.
- Memory: Memory cells are created, so your immune system can quickly react to the pathogen in the future.
Therefore, resistance to strep throat after a previous infection and immunity due to the polio vaccine are examples of active immunity, showcasing how your body can develop its own protection through antibodies.
