Pathogenic is an adjective referring to the ability of a biological agent or substance to cause disease or illness in a host organism. Derived from the Greek words "pathos" meaning suffering, and "genesis" meaning origin, pathogenic describes the capability of a microorganism, such as bacteria, virus, fungus, or parasite, to produce pathological changes in a living organism.
The term is commonly used in the field of microbiology, medicine, and infectious diseases to describe the nature of disease-causing agents. Pathogenicity is the degree to which a microorganism causes disease, and pathogenesis is the mechanism by which the agent causes illness in the host. Microorganisms that are pathogenic often possess certain virulence factors that aid in their ability to invade, colonize, or damage host tissues. These may include specific genetic elements, enzymes, toxins, or cellular properties.
Pathogenic microorganisms can cause a wide range of diseases in humans, animals, and plants. Examples of well-known pathogenic microorganisms include Streptococcus pneumoniae, responsible for pneumonia and other respiratory infections, and Salmonella enterica, which causes food poisoning. Understanding the pathogenicity of microorganisms is essential for diagnosis, treatment, prevention, and control of infectious diseases. Antimicrobial therapies, vaccines, and sanitation practices are developed based on this understanding to combat pathogenic microorganisms and protect public health.
