The chain of infection is the way infections are able to spread. It consists of six elements. Learn more about it on http://chainofinfection.org

1. The Chain of Infection
http://chainofinfection.org

2. Chain of infection
The "chain of infection" is the name of the model that
describes the way how infections spread through a
population.
This chain of infection is made up by six different elements.
All these elements need to be present and linked to each
other in order for an infection to be able to spread.
Because of the fact that they need to be linked, it is called
the chain of infection.
http://chainofinfection.org

3. Chain of infection diagram
http://chainofinfection.org

4. Chain of infection - elements
Infectious agent
This infectious, or etiologic, agent is any microorganism that is capable of producing an infection.
Reservoir
This is the place where the microorganism resides. It can be a food or water source, but it can also have a human source such as
feces and respiratory secretions
Portal of exit
In order for an etiologic agent to establish an infection, the microorganism needs to leave the reservoir. In humans this portal of
exit can be the nose, mouth, urethral meatus, open wounds, vagina, or rectum.
Mode of transmission
This is the method of transfer by which the organism moves or is carried over to another host. Direct transmission involves direct
contact between the infectious person and the susceptible host. Indirect transmission involves an intermediate means that
caries the infectious agent to the host For example the hands of the health care worker may carry bacteria from one person to
another (direct transmission) or the bacteria might be left behind on a doorknob and are picked up later by the susceptible host
(indirect transmission)
Portal of entry
The portal of entry is the place where the microorganism can enter the host. Portals include body orifices, mucus membranes, or
breaks in the skin. Portals also result from tubes placed in body cavities, such as urinary catheters, or from punctures produced
by invasive procedures such as intravenous fluid replacement.
Susceptible host
A person who cannot resist a microorganism invading the body, multiplying, and resulting in infection. The host is susceptible to
the disease, lacking immunity or physical resistance to overcome the invasion by the pathogenic microorganism.
http://chainofinfection.org

5. More info:
http://chainofinfection.org
http://chainofinfection.org