The Chain of Transmission is a visual tool that helps illustrate all the components at play during the acquisition of infectious agents. It is applicable to all environments (e.g. hospital, home and community), but the examples given below will be focused on healthcare settings. Each element in the chain is a topic in and of itself, and the subject of further analysis.
Susceptible HostA person who does not have immunity to the infectious agent or is susceptible as result of being immune-compromised.
Infectious AgentsInfectious agents include bacteria, viruses, yeasts, fungi, parasites and prions.
Portal of EntryA pathway by which an infectious agent can enter a host.
ReservoirA reservoir is a place where an infectious agent can live and reproduce.
Mode of TransmissionA reservoir is a place where an infectious agent can live and reproduce.
Portal of ExitA pathway by which an infectious agent can escape its reservoir.
Content created by Claudia Crussell-Balogh, CIC, MHSc.