👉 Infection is a biological process where a pathogen, such as a bacterium, virus, fungus, or parasite, invades and colonizes a host organism, disrupting its normal functioning. This invasion can occur through various routes, including ingestion, inhalation, or direct contact. Once inside the host, the pathogen begins to multiply and spread, often evading or suppressing the host's immune defenses. The interaction between the pathogen and the host's cells can lead to inflammation, tissue damage, and disease symptoms. For example, a bacterial infection might cause an immune response that results in fever and swelling, while a viral infection could lead to cell damage and symptoms like coughing or fatigue. Understanding infection is crucial for developing treatments and preventive measures, such as antibiotics, antivirals, and vaccines, to combat these harmful invaders and protect health.
