👉 Infection occurs when a pathogen, such as bacteria, viruses, fungi, or parasites, enters a host and begins to multiply, often causing disease. This process involves the pathogen adhering to and invading host cells, either by directly penetrating them or by exploiting cellular pathways. Once inside, the pathogen can replicate, sometimes leading to cell damage or death, and triggering an immune response from the host. However, if the infection is severe or the host's defenses are weakened, the pathogen can spread, potentially affecting multiple systems and causing illness. Understanding infection is crucial for developing treatments and preventive measures, such as antibiotics for bacterial infections, antivirals for viral diseases, and vaccines to boost immunity.
