👉 Infection occurs when a pathogen, such as a virus, bacterium, or parasite, enters a host and begins to multiply, often causing harm or disease. This process typically involves the pathogen attaching to host cells, either by binding to specific receptors on the cell surface, and then either injecting its genetic material or directly taking over cellular functions to reproduce. The host's immune system may recognize the invader and mount a defense, but if the pathogen is highly virulent or the host's defenses are weakened, infection can lead to symptoms ranging from mild discomfort to severe illness or even death. Preventive measures, such as vaccination, hygiene practices, and antibiotics for bacterial infections, aim to reduce the risk of infection by either blocking entry points or enhancing the body’s ability to combat the pathogen.
