👉 Infection is a biological process where a pathogen, such as a bacterium, virus, fungus, or parasite, enters a host organism and begins to multiply, often causing disease. This entry can occur through various routes, including ingestion, inhalation, skin contact, or vector-borne transmission. Once inside the host, the pathogen must evade or overcome the host's immune defenses to establish itself. The interaction between the pathogen and the host's cells can lead to inflammation, tissue damage, and systemic effects, depending on the type of pathogen and the host's response. For instance, bacterial infections might cause localized swelling and fever, while viral infections can lead to more widespread symptoms like fatigue and muscle aches. Fungal infections often affect the skin, nails, or lungs, and parasitic infections can invade various organs or tissues. The severity and outcome of an infection depend on factors such as the pathogen's virulence, the host's immune system strength, and environmental conditions. Understanding these dynamics is crucial for developing effective treatments and preventive measures.
