Infection Control & Isolation Flashcards
chain of infection
a chain of necessary pieces needed for an infection to occur and includes the following links:
1. infectious agent
2. reservoir
3. portal of exit
4. mode of transmission
5. portal of entry
6. susceptible host
A break in any of the links of this chain can prevent the development of an infection.
infectious agent
something that contains bacteria, fungi, virus, parasite, prion.
resident flora
the bacteria that live on or in a client and help protect the body from infection.
…can become an infectious agent when moved to a different location of the body; for example, flora from the gastrointestinal tract can move elsewhere in the body and create infection there.
reservoir
the habitat of the infectious agent; a location where it can live, grow, and reproduce itself or replicate.
portal of exit
means by which the infectious agent can leave the reservoir.
can be any body orifice - ears, nose, mouth…
other portals of exit include blood or body fluids that leave the body through the gastrointestinal tract, respiratory tract, skin…
mode of transmission
the moving of bacteria, viruses, fungi, parasites, and prions from place to place. These are contact, droplet, airborne, vehicle, and vector-borne transmission.
portal of entry
any body orifice that provides a place for the infectious agent to enter and replicate or for the toxin to act.
susceptible host
required for the infectious agent to take hold and become a reservoir for infection. Not everyone who is exposed to an infectious agent will get ill. Some people never exhibit manifestations at all but can become colonized (temporarily or permanently) with the infectious agent.
Factors that increase host susceptibility
Age
Underlying disease
HIV/AIDS
Malignancy
Transplants
Medications: immunosuppressants, antirejection medications, antineoplastics, antimicrobials, corticosteroids, gastric suppressants (e.g., proton pump inhibitors)
Surgical procedures
Radiation therapy
Indwelling devices: endotracheal tubes, urinary catheters, central venous catheters, arterial catheters, and implants such as pacemakers and artificial joints.
Three main modes of transmission
contact
droplet
airborne
contact transmission
transmitted by contact with an object or a person
droplet transmission
transmitted through droplets from activities such as coughing, sneezing, and singing.
airborne transmission
transmitted through the air
vector transmission
transmitted by insects
vehicle transmission
transmitted by contaminated water
direct contact transmission
occurs when microorganisms are directly moved from an infected person to another person, rather than through a contaminated object or person.
Example: a client’s blood coming in contact with an open abrasion on a nurse’s skin. If a nurse is caring for a client who has scabies and is not wearing gloves, the scabies mites can directly contact the nurse’s skin.
indirect contact transmission
occurs when microorganisms are directly moved from the infected person to another person with having a contaminated object or person between these two.