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
There are six links in the chain of infection :
1st - The Infectious Agent -any disease-causing microorganism (pathogen)
Infection Control Microorganism a small living organism that is not visible to the naked eye; found everywhere in the environment Normal flora-plant life adapted for living in a specific environment; important for maintaining certain body processes; nonpathogenic Pathogen-disease or infection causing microorganism
Types of Microorganisms Bacteria Simple, one-celled organisms that multiply rapidly Classified by shape and arrangement (cocci, bacilli, spirilla Examples of disease caused by bacteria include gonorrhea, meningitis, strep throat, botulism Antibiotics are used to kill bacteria
Types of Microorganisms Protozoa One-celled animal-like organisms often found in decayed materials and contaminated water Cause diseases such as malaria, amebic dysentery, trichomonas
Types of Microorganisms Fungi Simple, plant-like organisms that live on dead organic matter Yeasts and molds are two common forms that can be pathogenic Cause diseases such as ring worm, athlete s foot, yeast vaginitis, and thrush Treated with antifungals
Types of Microorganisms Rickettsiae Parasitic microorganisms commonly found in fleas, lice, ticks, and mites Cause diseases such as typhus fever, Rocky Mountain Spotted fever Antibiotics are effective against many rickettsiae
Types of Microorganisms Virus Smallest microorganism, visible only with an electron microscope Cannot reproduce unless inside another living cell More difficult to kill because resistant to many disinfectants and are not affected by antibiotics. Cause diseases such as common cold, herpes, chicken pox, AIDS, Hepatitis
2nd - The Reservoir Host -the organism in which the infectious microbes reside
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. Examples: respiratory secretions, blood exposure, breaks in skin
4th - The Route of Transmission -method by which the pathogen gets from the reservoir to the new host
Transmission may occur through: direct contact air insects
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.
How to interrupt the chain of infection: -The essential part of patient care & self-protection.
1. Pathogen Identification -identification of infectious agent & appropriate treatment
2. Asepsis & Hygiene -potential hosts & carriers must practice asepsis & maintain proper personal hygiene
3. Control Portals of Exit -healthcare personnel must practice standard precautions any time they might possibly come into contact with blood or other body fluids :
(Control body secretions & wash hands according to protocol.)
4. Prevent a Route of Transmission -prevent direct or indirect contact by: 1. Proper handwashing (#1 way to prevent the spread of infection!) 2. Disinfection & sterilization techniques 3. Isolation of infected patients 4. Not working when contagious
5. Protect Portal of Entry -Health professionals must make sure that ports of entry are not subjected to pathogens. (nose, mouth, eyes, urinary tract, open wounds, etc.)
6. Recognition of Susceptible Host -health professionals must recognize & protect high-risk patients
Cancer Patients AIDS Patients Transplant Patients Infant & Elderly Patients
The Chain of Infection Infectious Agent Reservoir Host Susceptible Host Portal of Exit Portal of Entry Mode of Transmission
Chain of infection Infectious agent Reservoir Host Portal of Exit Mode of Transmission Portal of Entry Susceptible host..and back to the infectious agent!
How to Don a Gown Select appropriate type and size Opening is in the back Secure at neck and waist If gown is too small, use two gowns Gown #1 ties in front Gown #2 ties in back PPE Use in Healthcare Settings
How to Don a Mask Place over nose, mouth and chin Fit flexible nose piece over nose bridge Secure on head with ties or elastic Adjust to fit PPE Use in Healthcare Settings
How to Don Eye and Face Protection Position goggles over eyes and secure to the head using the ear pieces or headband Position face shield over face and secure on brow with headband Adjust to fit comfortably PPE Use in Healthcare Settings
How to Don Gloves Don gloves last Select correct type and size Insert hands into gloves Extend gloves over isolation gown cuffs PPE Use in Healthcare Settings
Contaminated and Clean Areas of PPE Contaminated outside front Areas of PPE that have or are likely to have been in contact with body sites, materials, or environmental surfaces where the infectious organism may reside Clean inside, outside back, ties on head and back Areas of PPE that are not likely to have been in contact with the infectious organism PPE Use in Healthcare Settings
Sequence for Removing PPE 1 st : Gloves 2 nd : Face shield or goggles 3 rd : Gown 4 th : Mask or respirator PPE Use in Healthcare Settings
How to Remove Gloves (1) Grasp outside edge near wrist Peel away from hand, turning glove inside-out Hold in opposite gloved hand PPE Use in Healthcare Settings
How to Remove Gloves (2) PPE Use in Healthcare Settings Slide ungloved finger under the wrist of the remaining glove Peel off from inside, creating a bag for both gloves Discard
Remove Goggles or Face Shield Grasp ear or head pieces with ungloved hands Lift away from face PPE Use in Healthcare Settings Place in designated receptacle for reprocessing or disposal
Removing Isolation Gown PPE Use in Healthcare Settings Unfasten ties Peel gown away from neck and shoulder Turn contaminated outside toward the inside Fold or roll into a bundle
Removing a Mask Untie the bottom, then top, tie Remove from face Discard PPE Use in Healthcare Settings
Hand Hygiene Perform hand hygiene immediately after removing PPE. If hands become visibly contaminated during PPE removal, wash hands before continuing to remove PPE Wash hands with soap and water or use an alcohol-based hand rub * Ensure that hand hygiene facilities are available at the point needed, e.g., sink or alcohol-based hand rub PPE Use in Healthcare Settings
What Type of PPE Would You Wear? ***Answer these questions on a separate sheet of paper and turn in*** Giving a bed bath? Suctioning oral secretions? Transporting a patient in a wheel chair? Responding to an emergency where blood is spurting? PPE Use in Healthcare Settings Drawing blood from a vein? Cleaning an incontinent patient with diarrhea? Irrigating a wound? Taking vital signs?