👉 Infection is a biological process where a pathogen, such as a virus, bacterium, or parasite, enters and takes control of a host cell, multiplying and causing harm to the host's tissues and organs. This occurs when the pathogen breaches the body's defenses, often through entry points like the respiratory tract, skin, or digestive system. Once inside, the pathogen can replicate rapidly, leading to symptoms ranging from mild discomfort to severe illness. Understanding infection involves recognizing how pathogens invade, evade the immune system, and cause disease, which is crucial for developing treatments and preventive measures like vaccines and antibiotics.
