Download The Chain of Infection

The Chain of Infection
The chain of infection has six links:
Understanding the chain
of infection and how
pathogens travel makes
it easier to act at the right
time and at the right
place for better results.
It makes it easier to
optimize resources to
efficiently prevent the
spread of pathogens.
Eliminating just one these
steps will break the chain,
making it much less likely
— if not impossible —
for infection to spread.
Break the chain of
infection with frequent
cleaning and disinfection
of environmental surfaces
and ensure hand hygiene
and isolation protocols
and guidelines are strictly
followed.
1.The infectious agent or pathogen
These can be bacteria, viruses, spores or fungi.
2.The reservoir
This is where pathogens can thrive and reproduce, such
as environmental surfaces like light switches. Pathogens
on such surfaces can easily spread to a hand and onto
another surface. A person can also be a pathogen reservoir.
Where germs live in a person’s body determines how they
exit the body and contaminate other people or objects.
It also determines how they attach to or enter the bodies
of other people and potentially cause illness.
3.The portal of exit
Pathogens can leave reservoirs via various paths.
Gastrointestinal pathogens
Exit path: vomit and diarrhea.
How to break the chain: By isolating infected people or restricting them from certain objects
and areas.
Respiratory pathogens
Exit path: sneezing, coughing, and even tiny droplets from the mouth when talking.
How to break the chain: By sneezing into one’s elbow, and by having sick people use a respiratory
mask when in the presence of healthy people.
Bloodborne pathogens
Exit path: only through the blood or body fluids of an infected person.
How to break the chain: By enforcing special sanitation rules for blood and body fluids, as well as
procedures for safely handling and disposing needles. Sweat is not considered a body fluid from a
disease-transmission point of view.
Chain of Infection
4. The mode of transmission
Remember that to remain
healthy, you must reduce
the risk of a pathogen
leaving the body of a sick
or infected person and
entering your body,
making you sick. To stay
healthy, we have to break
the chain of infection
and adapt our cleaning
programs to optimize
our chances of success.
Strategies that break the
chain of infection prevent
the spread of illnesses
and reduce overall costs.
Once the germ leaves the reservoir, it must come into contact with objects or people, be ingested
or inhaled.
Through contact
Isolate objects and areas to limit transmission. Thoroughly clean and disinfect elements of
transmission. Frequency of cleaning and disinfecting environmental surfaces is also crucial for
controlling the spread of germs through contact.
Through inhalation
Isolate sick individuals so that healthy people do not breathe contaminated droplets. Renew the
ambient air more often; separate ventilation systems will also help to prevent the spread of
airborne germs.
Many germs have more than one mode of transmission. People may also need to fight off more
than one contagious infection at a time. In some situations, it may be necessary to implement a
combination of strategies for preventing transmission.
5. The portal of entry
Through contact
Isolate healthy people from infected objects and areas to limit exposure and possible
transmission. Wearing disposable gloves, gowns and protective eyewear can protect against
contacting or ingesting pathogens.
Through inhalation
Wear a suitable respiratory mask to protect against respiratory pathogens. Not all masks are
equal, however. Only individuals who have done an fit test and who have received appropriate
training should use respiratory protection equipment. Individuals who have not done an fit test
and received the appropriate training should not enter the isolation area of an individual with an
infectious respiratory disease.
Hand hygiene is effective for breaking the chain of infection, primarily when it comes to the portal
of exit, the mode of transmission and the portal of entry. For this reason, frequent and effective
hand hygiene is the best way to keep oneself and others healthy.
6. The susceptible host
Humans and other living matter possess an immune system that always defends against
pathogen attacks. People can naturally develop a resistance or immunity to certain pathogens.
In the industrialized world, we use immunization to confer protection against certain diseases.
When a vaccine is available for protection against an infection, it is recommended that the
vaccination be taken. This will protect you while also preventing you from spreading the
disease to others.