Pathogen

A microorganism capable of causing disease

Definition

A pathogen is any disease-causing microorganism. Bacteria, virus, fungus, parasite, or prion, that invades and harms a host.

Types

  • Bacteria: E. coli, Staph aureus, Streptococcus, TB.
  • Viruses: Influenza, SARS-CoV-2, HIV, HPV.
  • Fungi: Candida, Aspergillus, Pneumocystis.
  • Parasites: Giardia, Plasmodium (malaria).
  • Prions: Creutzfeldt-Jakob disease.

Transmission

  • Direct contact
  • Droplet
  • Airborne
  • Vector-borne (mosquito, tick)
  • Fecal-oral
  • Sexual
  • Blood-borne

Nursing Considerations

Apply appropriate isolation precautions based on transmission route. Hand hygiene remains the most important prevention measure. Support immune function through nutrition, hydration, and vaccinations.

NCLEX Relevance

Match pathogen to isolation type. High-yield infection control.