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Published on: April 2, 2013

Pathogenicity and virulence

Stephen R Thomas1, Joseph S Elkinton

  • 1Graduate Program in Organismic and Evolutionary Biology and Department of Entomology, University of Massachusetts, Amherst, MA 01003, USA.

Journal of Invertebrate Pathology
|April 28, 2004
PubMed

Insights

Pathogenicity and virulence definitions vary across scientific fields. This study clarifies that pathogenicity is the broader term, encompassing virulence, which measures disease severity in infected hosts.

Area of Science:

  • Host-pathogen interactions
  • Invertebrate pathology
  • Disease ecology

Background:

  • Invertebrate pathology and related fields lack standardized definitions for pathogenicity and virulence.
  • Existing definitions vary across disciplines, leading to confusion in host-pathogen research.

Purpose of the Study:

  • To survey and synthesize definitions of pathogenicity and virulence across various scientific disciplines.
  • To propose a unified understanding of these terms for invertebrate pathology.

Main Methods:

  • Literature review across plant pathology, invertebrate pathology, evolutionary biology, and medicine.
  • Analysis of definitions and their application in host-pathogen interaction studies.

Main Results:

  • Pathogenicity is broadly defined as the ability to cause disease, encompassing virulence.
  • Virulence is defined as the severity of disease manifestation, measurable only in infected individuals.
  • Definitions apply to both lethal and non-lethal diseases.

Conclusions:

  • Clarifying pathogenicity and virulence enhances precision in host-pathogen research.
  • Standardized definitions are crucial for consistent experimental design and interpretation in invertebrate pathology.
  • Distinguishing between pathogenicity and virulence aids in understanding disease dynamics.

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