This document discusses infection control practices including breaking the chain of infection. It defines key terms like pathogens, virulence, infection, and colonization. It describes the chain of infection involving an infectious agent, reservoir, portals of exit and entry, and a susceptible host. It also outlines normal defense mechanisms like skin and mucous membranes, as well as specific immune responses. Common sites of nosocomial infections are identified and methods for reducing infectious agents through cleansing, disinfection and sterilization are discussed.

1. INFECTION CONTROL
ANES 1501
Introduction to Anesthesia
Technology
College of DuPage

2. INFECTION CONTROL
Infection control practices are
directed at controlling or
eliminating sources of infection
in the health care agency,
home, or community.

3. PATHOGENS AND INFECTION
TERMINOLOGY
 Pathogenicity is the ability of a microorganism to
produce disease.
 Microorganisms that cause diseases in humans are called
pathogens.
Virulence is the degree of pathogenicity of an
infection’s microorganism.
Infection is an invasion and multiplication of
microorganisms in body tissue that results in cellular
injury.
 These microorganisms are called infectious agents.

4. CONTINUED
Communicable Disease
 The result of a communicable agent being transmitted to a client by
direct or indirect contact, through a vehicle (or vector) or airborne route
Colonization is the multiplication of
microorganisms on or within a host that does
not result in cellular injury.
Flora are the vegetation of microorganisms on
the human body.
 Resident flora
 Transient flora

5. AGENT, HOST, AND ENVIRONMENT
Agents capable of causing disease:
 Biological agents
 Chemical agents
 Physical agents

6. AGENT, HOST AND ENVIRONMENT
The environment consists of everything other than
the agent and host.
 Water, food, plants, animals
 Housing conditions
 Noise
 Meteorological conditions
 Environmental chemicals

7. CHAIN OF INFECTION
Microorganism (infectious agent)
 Source or reservoir
 Portal of exit from reservoir
 Mode of transmission
 Portal of entry into host
 Susceptible host

8. INFECTIOUS AGENTS
(MICROORGANISMS
Agents that produce infections can consist of:
 Bacteria
 Viruses
 Fungi
 Protozoa
 Rickettsia

9. INFECTIOUS AGENTS
The ability of a microorganism to infect a client is
related to:
 Virulence of the agent
 Number of microorganisms present
 Ability of the agent to enter and live in the client
 Susceptibility of the client

10. INFECTIOUS AGENTS
 Resident Infectious Agents
 Microorganisms which are always present on skin.
 Can be reduced through handwashing, but not
totally removed.

11. INFECTIOUS AGENTS
Transient Infectious Agents
 Agents that are picked up by the skin from another
person or object.
 Attach themselves to the skin and then may be
transmitted to a susceptible host.

12. SOURCE OR RESERVOIR
Required for the microorganism to survive while
awaiting a host.
May allow the organism to multiply, making it more
dangerous.
 The human body is the most common reservoir.
 Food, plants, animals, and feces are other common
reservoirs.

13. PORTAL OF EXIT
Pathway by which pathogens leave the body of a
host. Accessed by:
 Direct Contact
 Indirect Contact
 Airborne Transmission

14. PORTAL OF EXIT
Direct Contact
 Transmission of disease from the host
 Touching, kissing, and sexual intercourse
Sources of Direct Contact
 Skin, mucus membranes, urine, feces, reproductive
tract, blood

15. PORTAL OF EXIT
Indirect Contact
 Occurs with the use of vehicles and vectors
Vehicles (fomites)
 Toys, hospital supplies, instruments, dishes, cups,
or surgical dressings, food, fluids, blood

16. PORTAL OF EXIT
Airborne Transmission
 Transmission of infectious agents through
coughing, sneezing, dust particles
 Usually entry via the person’s respiratory tract

17. PORTAL OF ENTRY
Pathway by which infectious agents gain access to
the body

18. SUSCEPTIBLE HOST
A person with a reduced immune response has
increased susceptibility.
The immune response is the body’s natural defense
against infection.

19. FACTORS INFLUENCING
PRODUCTION OF AN INFECTIOUS
DISEASE
Age
Heredity
Stress
Surgery
Nutrition
Health Status

20. FACTORS INFLUENCING
PRODUCTION OF AN INFECTIOUS
DISEASE
Age
 The elderly and children under two years of age are
at greatest risk.
Heredity
 Conditions or diseases resulting in the absence of or
inability to form immune defenses.

21. FACTORS INFLUENCING
PRODUCTION OF AN INFECTIOUS
DISEASE
Stress
 Increase in metabolic rate which results in using up
stored energy
 Elevation of blood cortisol, decreasing anti-
inflammatory responses
 Continued stress produces exhaustion, further
depleting ability to ward off infection.

22. FACTORS INFLUENCING
PRODUCTION OF AN INFECTIOUS
DISEASE
Surgery
 Eliminates primary barrier of infection.
 Predisposes clients to surgical site infections.
 Localized infection at wound site can progress to a
systemic infection.
 Additional risks include catheters and tubes

23. FACTORS INFLUENCING
PRODUCTION OF AN INFECTIOUS
DISEASE
Nutrition
 Insufficient protein consumption reduces antibody
production and inhibits the body’s ability to ward off
infection.
Health Status
 Clients with disease of their immune system are at
greater risk.
 Chronic diseases can predispose the client to
infection.

24. NORMAL DEFENSE MECHANISMS
Nonspecific and specific immune defenses work in
harmony to defend the host from pathogens.

25. NORMAL DEFENSE MECHANISMS
Nonspecific Immune Defenses
 Protect the host from all microorganisms
 Not dependent on prior exposure to the antigen

26. NONSPECIFIC IMMUNE DEFENSES
Skin and Normal Flora
Mucous Membranes
Sneeze, Cough Reflexes
Tearing Reflexes
Elimination
Acidic Environment
Inflammatory Response

27. NONSPECIFIC IMMUNE DEFENSES
Skin
 Intact skin is the body’s first line of defense against
infection.
 Sebum is produced by the skin and contains fatty
acids that kill some bacteria.

28. NONSPECIFIC IMMUNE DEFENSES
Normal Flora
 Normal flora residing on the skin compete with
pathogenic flora for food and inhibit their
multiplication.
 Inappropriate antibiotic use may disrupt the balance
of normal flora.

29. NONSPECIFIC IMMUNE DEFENSES
Mucous Membranes
 Mucus entraps infectious agents and contains
substances that inhibit bacterial growth.
 Cilia trap and propel mucus and microorganisms
away from the lungs.

30. NONSPECIFIC IMMUNE DEFENSES
Sneeze and Cough Reflexes
 Physically expel mucus and microorganisms from
the respiratory tract and oral cavity with force
Tearing Reflex
 Protects the eyes by continually flushing away
microorganisms

31. NONSPECIFIC IMMUNE DEFENSES
Elimination Patterns and Acidic Environment
Resident flora of the large intestines
Mechanical process of defecation
Flushing action of urination
Acidic environment of urine and vagina

32. NONSPECIFIC IMMUNE DEFENSES
Inflammatory Response
 Tissue injury caused by bacteria, trauma, chemicals, heat, or
any other phenomenon
 Release of substances that produce secondary changes in the
tissue

33. SPECIFIC IMMUNE DEFENSE (THE
IMMUNE RESPONSES)
Immunity is a specific defense mechanism that
creates an immune response to a specific
invading antigen.

34. SPECIFIC IMMUNE DEFENSE (THE
IMMUNE RESPONSES)
Immune Responses
Active immunity
Passive immunity
Acquired immunity
Natural immunity
Artificial immunity

35. IMMUNE RESPONSES
Active immunity results from the development within
the body of antibodies that neutralize the infective
agent.
Passive immunity is acquired by the introduction of
preformed antibodies.

36. IMMUNE RESPONSES
Acquired immunity results either from exposure to
an antigen or from the passive injection of
immunoglobulins.
Natural immunity refers to the genetically determined
response of protection within a specific species.
Artificial immunity is produced following a vaccine.

37. THE HUMORAL IMMUNE RESPONSE
B lymphocytes recognize the antigen as an enemy.
Immunoglobulins are plasma protein cells that
produce five different classes of antibodies (IgM, IgG,
IgA, IgD, and IgE).
Immunoglobulins circulate throughout the
bloodstream for the purpose of destroying antigens.

38. CELL-MEDIATED IMMUNITY
Fights pathogens that survive inside cells.
Antigen stimulates the release of activated T cells.
T-helper cells
T-suppressor cells
T-cytotoxic cells

39. LOCALIZED VERSUS SYSTEMIC
INFECTIONS
Infection results from tissue invasion and damage by
an infectious agent.
Localized infections are limited to a defined area or
single organ.
Systemic infections affect the entire body and
involve multiple organs.

40. FOUR STAGES OF INFECTION
Incubation
Prodromal
Illness
Convalescence

41. NOSOCOMIAL INFECTIONS
Infections acquired in a health care setting that were
not present or incubating at the time of the client’s
admission

42. COMMON SITES OF NOSOCOMIAL
INFECTIONS
Urinary tract
Surgical sites
Respiratory tract

43. NOSOCOMIAL INFECTIONS
Procedures identified as possible sources of infection
are:
Inadequate handwashing
Catheterization technique
Improper suctioning technique
Improper dressing-change technique
Contamination of closed drain system

44. INFECTION CHAIN
Breaking the chain
of infection;
preventive measures
follow each critical
link in the chain of
infection.

45. ASEPSIS
Asepsis is the absence of microorganisms.
Aseptic technique is the infection control practice
used to prevent the transmission of pathogens.

46. MEDICAL ASEPSIS (CLEAN
TECHNIQUE)
Practices to reduce the number, growth, and spread
of microorganisms
The most common cause of nosocomial infections is
contaminated hands of health care providers.
Wash hands before and after every client contact.

47. SURGICAL ASEPSIS (STERILE
TECHNIQUE)
Practices that eliminate all microorganisms and
spores from an object or area
Surgical scrub
Surgical attire
Sterile fields
Sterile instruments and equipment

48. REDUCE OR ELIMINATE
INFECTIOUS AGENTS
Infection control practices to break the chain of
infection
Cleansing
Disinfection
Sterilization

49. REDUCE OR ELIMINATE
INFECTIOUS AGENTS
Cleansing
Removal of soil or organic material from instruments
and equipment used in providing care
Water, mechanical action, detergent

50. REDUCE OR ELIMINATE
INFECTIOUS AGENTS
Disinfection
Elimination of pathogens, except spores, from
inanimate objects
Use of germicides and antiseptics.

51. REDUCE OR ELIMINATE
INFECTIOUS AGENTS
Sterilization methods used for total elimination of all
microorganisms including spores are:
Moist heat or steam (autoclave, boiling water)
Radiation
Chemicals
Ethylene oxide gas
Plasma
Sterrad

52. REDUCE OR ELIMINATE
INFECTIOUS AGENTS
Home Health Care Considerations
Adapting acute care infection control practice to the
home care setting involves:
Cleaning and disinfecting equipment
Using clean versus sterile technique
Handling of the nursing supply bag

53. REDUCE OR ELIMINATE
INFECTIOUS AGENTS
Disposal of Infectious Waste in the Home
Biological Hazard Symbol
OSHA Regulations

54. GUIDELINES FOR STANDARDS
PRECAUTIONS
Barrier Precautions
Use of masks, gowns, and gloves to minimize the
risk of exposure to blood and body fluids

55. GUIDELINES FOR STANDARDS
PRECAUTIONS
Body Substances
Blood
All body fluids
Secretions
Contaminated items regardless of whether or not
they contain visible blood
Nonintact skin
Mucous membranes

56. ROLE OF HEALTH CARE
PERSONNEL AND HEALTH
AGENCIES IN INFECTION CONTROL
Mask and eye protection or face shield
Non-sterile gown
Tuberculosis masks
Isolation precautions initiated when positive cultures
from a draining wound are reported

57. ROLE OF HEALTH CARE
PERSONNEL AND HEALTH
AGENCIES IN INFECTION CONTROL

58. ROLE OF HEALTH CARE
PERSONNEL AND HEALTH
AGENCIES IN INFECTION CONTROL
Reinforce adherence to isolation.
Post signs indicating type of isolation.
Provide necessary supplies.
Place clients in a private room with adequate
ventilation.
Use disposable supplies and equipment.

59. ROLE OF HEALTH CARE
PERSONNEL AND HEALTH
AGENCIES IN INFECTION CONTROL
Labeling of all articles leaving the room
Use of impermeable bags or double bagging
Client and family instruction
Alert to psychological discomfort

60. ROLE OF HEALTH CARE
PERSONNEL AND HEALTH
AGENCIES IN INFECTION CONTROL
Blood Borne Pathogen Exposure
 OSHA requires that all health agencies make available the
hepatitis B vaccine and vaccination series to all employees.

61. ROLE OF HEALTH CARE
PERSONNEL AND HEALTH
AGENCIES IN INFECTION CONTROL
Exposure Control Plan
Begins with standard precautions and moves to
postexposure prophylaxis
Specific follow-up for blood-borne pathogens
Postexposure prophylaxis only in cases of highest
risk

62. ALTERNATIVE THERAPIES USED TO
TREAT INFECTIONS
Herbal Products
Antimicrobial action
Augment and vitalize the body’s own defenses
Client’s alternative practices should be documented.
Possible adverse reactions are possible when used
with prescribed drugs.