👉 Infection refers to the process by which a pathogen, such as a virus, bacterium, fungus, or parasite, enters and begins to multiply within a host organism, leading to disease. This process can occur through various routes, including respiratory droplets, contaminated food or water, vectors like insects, or direct contact with infected bodily fluids. Once inside the host, the pathogen must evade or overcome the body's immune defenses to establish itself. The interaction between the pathogen and the host's cells is critical; for instance, viruses hijack cellular machinery to replicate, while bacteria may produce toxins that damage tissues. The severity of infection depends on factors like the pathogen's virulence, the host's immune response, and environmental conditions. Understanding infection mechanisms is crucial for developing treatments and preventive measures, such as vaccines and antibiotics, to mitigate the impact of infectious diseases.
