A pathogen is a microscopic organism, such as a virus, bacterium, fungus, or parasite, that causes disease in its host organism. These infectious agents invade living cells, disrupting normal bodily functions and triggering immune responses.
Pathogens can spread through various means, including air, water, food, and direct contact with infected individuals.
They are responsible for a wide range of illnesses, from common colds and flu to more severe conditions like tuberculosis, malaria, and COVID-19. Understanding and controlling pathogens are crucial for public health and disease prevention efforts.
