Foundational concept · reviewed

Germ theory

Developed across the 19th century

Germ theory attributes particular diseases and biological processes to microorganisms.

Nineteenth-century work by Pasteur, Koch, and many predecessors replaced broad spontaneous-generation and miasmatic explanations with experimentally testable microbial causes, though acceptance was gradual and uneven. The theory did more than identify invisible agents; it suggested testable routes of transmission and practical methods of prevention. Sterilization, antisepsis, vaccination, laboratory culture, sanitation, and infection control all became easier to explain and improve within this framework.

Sources

A Brief History of Microbiology and Immunology — Arthur M. Silverstein, 2010

Concept map · prerequisites lead toward this node; descendants continue outward.

Vibrio bacteria seen with a scanning electron microscope — A public-domain scanning electron micrograph of curved Vibrio bacteria. Photo Credit: Janice Carr Content Providers(s): CDC/ Janice Carr. Public domain. Wikimedia Commons.

Direct relationships

Microscopy→Germ theoryMade microorganisms observable and experimentally distinguishable · medium confidence
Germ theory→Clinical handwashingSupplied a microbial explanation for hand hygiene · high confidence
Germ theory→Antiseptic surgerySupplied the microbial rationale for preventing wound infection · high confidence