Natural immunity is the inherent protection the body possesses against infections, while acquired immunity develops through exposure to pathogens or vaccination, creating a tailored defence system for long-term protection.
Natural Immunity
Natural immunity, also known as innate immunity, is your body's inborn ability to defend itself against pathogens (disease-causing microorganisms) without prior exposure to the specific pathogen. Think of it as your body's general, non-specific defence mechanisms.
Key Features of Natural Immunity
Physical and Chemical Barriers: Your skin, mucous membranes, and stomach acid act as physical barriers to prevent pathogens from entering your body.
Phagocytic Cells: Certain white blood cells, like neutrophils and macrophages, are always on the lookout for invaders. They engulf and digest pathogens.
Inflammatory Response: When an injury or infection occurs, your body initiates an inflammatory response. This process helps recruit immune cells to the site and can be seen as redness, swelling, and warmth. It's part of the body's effort to eliminate pathogens.
Complement System: A set of proteins in your blood that work together to identify and destroy pathogens.
Natural immunity is your immediate defence against any new pathogen, but it lacks specificity. It doesn't "remember" past pathogens. Therefore, it may not provide long-term protection against specific diseases.
Acquired Immunity
Acquired immunity, also known as adaptive immunity, is your body's ability to recognize and defend against specific pathogens after exposure or immunization. It's like having a tailored defence mechanism designed for a specific invader.
Key Features of Acquired Immunity:
Memory: One of the most remarkable aspects of acquired immunity is its ability to remember past encounters with pathogens. Once your body is exposed to a specific pathogen, it "learns" to recognize it and can mount a faster and more effective response if exposed again in the future. This is the basis for vaccines.
B Cells and Antibodies: B cells are a type of white blood cell that produces antibodies (proteins) specific to a particular pathogen. These antibodies can neutralize or mark the pathogen for destruction by other immune cells.
T Cells: T cells come in two main types: helper T cells and cytotoxic T cells. Helper T cells coordinate the immune response, while cytotoxic T cells directly attack infected cells.
Vaccination: Vaccination is a way to acquire immunity without getting sick. Vaccines contain weakened or inactivated forms of pathogens or pieces of the pathogen (antigens) that stimulate the immune system to produce a memory response. This way, if you encounter the actual pathogen, your immune system is ready to fight it off effectively.
In summary, natural immunity is your body's immediate, non-specific defence mechanism, while acquired immunity is a highly specific defence system developed after exposure to a specific pathogen or through vaccination. Acquired immunity's remarkable feature is its ability to remember and respond more effectively upon re-exposure to the same pathogen, providing long-lasting protection against various diseases.