Chain of Infection: Portal of Entry

Opposite the Portal of Exit is the Portal of Entry. This is any route that a pathogen uses to enter the body (host).


Examples include:

  • Inhalation (via the respiratory tract)
  • Absorption (via mucous membranes such as the eyes)
  • Ingestion (via the gastrointestinal tract)
  • Inoculation (as the result of an inoculation injury)
  • Introduction (via the insertion of medical devices)