Transcript The Chain of Infection

The Chain of Infection
As healthcare
professionals, it is
important to
understand two
things about
infection:
1.the various ways infection can
be transmitted
2. the ways the infection chain
can be broken
Types of Infections
• Endogenous
• Infection or disease originates within the
body
• Examples: Congenital (present at birth)
and tumors
Types of Infections
• Exogenous
• Nosocomial
• Infection or disease
• Infection acquired by
originates outside the
a person in a health
body
care facility or longterm care facility.
• Examples: pathogenic
organism that invade • Examples:
the body, trauma, and
Staphylococcus and
radiation
pseudomonas
Types of Infection
• Opportunistic
• Infections that occur when the body’s
defenses are weak.
• These infections do not usually occur if
people have intact immune systems.
• Examples: Pneumocystis Pneumonia in
individuals with AIDs
There are six
links
in the chain of
infection :
1st - The Infectious Agent
-any disease-causing
microorganism
(pathogen)
Bacteria, Protozoa,
Fungi, Rickettsia,
Viruses, Helminths
2nd - The Reservoir Host
-the organism in which the
infectious microbes reside
2nd - The Reservoir Host
•
•
•
•
Human Body
Animals
Environment
Fomites - objects
contaminated with
infectious material that
contains the pathogens
(doorknobs,bedpans,
instruments)
-
What are “Carrier Hosts”
Hosts that do not show any outward signs or
symptoms of a disease but are still capable
of transmitting the disease are known as
carriers.
3rd - The Portal of Exit
-route of escape of the pathogen
from the reservoir in which it
has been growing
Examples: respiratory
secretions, blood
exposure, breaks in
skin
rd
3
– The Portal of Exit
• Ways pathogens can leave the body:
• Urine and Feces
• Saliva
• Blood
• Tears
• Mucus Discharge
• Sexual Secretions
• Draining Wound
4th - The Route of
Transmission
-method by which the pathogen
gets from the reservoir to the
new host
Transmission may occur through:
direct contact – person to person
air
insects
Food
5th - The Portal of Entry
-route through which the
pathogen enters its new host
Respiratory System
Gastrointestinal System
Urinary & Reproductive Tracts
Breaks in Protective Skin Barrier
6th - The Susceptible Host
-the organism that accepts the
pathogen
The support of pathogen life & its
reproduction depend on the degree
of the host’s resistance.
Organisms with strong immune
systems are better able to fend off
pathogens.
Organisms with weakened immune
systems are more vulnerable to the
support & reproduction of pathogens.
•Cancer Patients
•AIDS Patients
•Transplant Patients
•Infant & Elderly
Patients
Remember--breaking the chain of
infection is the responsibility
of each health professional.