👉 Infection is a biological process where a microorganism, such as a bacterium, virus, fungus, or parasite, enters a host organism and begins to multiply, often causing harm or disease. This occurs when the pathogen breaches the body's natural barriers—like the skin or mucous membranes—and establishes itself within the host's tissues or bloodstream. The immune system typically responds by attempting to eliminate the invader through various defense mechanisms, but if the infection persists or the host's defenses are weakened, the pathogen can cause symptoms ranging from mild irritation to severe illness and even death. Understanding infection is crucial for developing effective treatments, preventive measures, and public health strategies to control and prevent the spread of diseases.
