Active immunity is a type of immunity that develops in response to exposure to a foreign substance, such as a pathogen or vaccine. It involves the activation of the body’s immune system to produce an immune response, including the production of antibodies and memory cells.
Active immunity can be acquired naturally or artificially. Natural active immunity occurs when a person is exposed to a pathogen, such as by getting infected with a virus or bacteria, and their immune system produces an immune response that leads to the production of antibodies and memory cells. As a result, the person develops immunity to the pathogen and is protected from future infections.
Artificial active immunity is achieved through vaccination. Vaccines contain a weakened or dead form of the pathogen or a part of it, such as a protein, that can stimulate the immune system to produce an immune response. The immune response results in the production of antibodies and memory cells, which provide protection against future infections with the pathogen.
Active immunity is long-lasting and can provide protection against a wide range of pathogens. The memory cells produced during an immune response can persist for many years, allowing the body to mount a rapid and effective immune response to a pathogen upon subsequent exposure. This is why vaccination is such an important tool in preventing the spread of infectious diseases, as it can provide long-term protection against the targeted pathogen.
Overall, active immunity is a vital component of the body’s immune system and is essential for protecting the body against infections and diseases.