Infectious agent
- Micro-organisms live in and outside of our bodies
- Generally harmless or even helpful
- An infectious agent (pathogen)
is a micro-organism with the ability to cause disease - This can be bacteria, viruses, fungi or parasites
Possibility of infection related to:
- Virulence (ability to grow / multiply)
- Invasiveness (ability to enter tissue)
- Pathogenicity (ability to cause disease)