Pathogen

Biological entity that causes disease in its host

In biology, a pathogen (from Greek πάθος (pathos) 'suffering, passion' and -γενής (-genēs) 'producer of'), in the oldest and broadest sense, is any organism, agent or micro-organism that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term pathogen came into use in the 1880s.

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