INFECTION CONTROL

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INFECTION CONTROL
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Introduction

• An infection is an invasion of the body by
  pathogenic microorganisms
• Disease results if the pathogens multiply and
  cause an alteration in normal tissue function
• Pathogenic organisms include bacteria, viruses,
  fungi, protozoa, and rickettsiae
• All organisms require food and the proper
  environment for growth

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Chain of Infection

• Development of an infection occurs in a cycle
  that depends on 6 elements
• 1. infectious agent or pathogen
• 2. reservoir or source for pathogen growth
• 3. portal of exit from the reservoir
• 4. mode of transmission
• 5. portal of entry to host
• 6. susceptible host

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Modes of Transmission

• Contact - Direct (between infected or
  colonized person and susceptible host)
• - Indirect (by contam. inanimate object -
  Droplet contact (travel up to 3 ft., not
  airborne)
• Air
• - droplet nuclei (residue of evaporated
  droplets remain suspended)

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Modes of Transmission (contd)

• Air (contd) - dust (contains infectious
  agents
• Vehicle - contaminated items, i.e.,
  liquids (water, drugs, blood) or food
• Vectors - insects, i.e., mosquito, fleas,
  ticks, lice - animals, i.e., cows, pigs

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Transmission (contd)

• Most microbial diseases are spread by the four
  Fs - fingers - flies -
  fomites - food

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Risk Factors for Infection

• Inadequate primary defenses
• - broken skin or mucosa - traumatized
  tissue - decreased ciliary action -
  obstructed urine outflow - altered
  peritalsis
• Inadequate secondary defenses - reduced
  hemoglobin - suppression of lymphocytes -
  low WBC count, suppress. immun.

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Nosocomial Infections

• Results from delivery of health services in a
  health care facility
• May be exogenous - from microbes external to
  pt. which are not part of normal flora
• May be endogenous - can occur when pt.s
  flora becomes altered, i.e., entercocci, yeast,
  streptococci

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Nosocomial (contd)

• To minimize the onset and spread of infection
  efforts must be directed toward aseptic
  techniques
• Medical asepsis (clean technique) - procedures
  used to reduce the of microbes and prevent
  spread, i.e., handwashing, changing linen daily
• Surgical asepsis (sterile technique)
• - eliminated microbes from an area, i.e.,
  O.R., suctioning, dressing changes

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Controlling Infection

• Preventing the onset and spread of infection and
  promoting measures for treatment of infection
• Prevent by - eliminating reservoirs of
  infection - avoiding actions that transmit
  microbes - disinfection and sterilization of
  supplies - strengthen hosts defenses, i.e.,
  nutrition

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Controlling Infect. (contd)

• Treatment of infection - eliminating the
  organisms - supporting pts defenses, i.e,
  bronchial hygiene

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Sputum Color

• Normally white and translucent
• Yellow indicates pus, since WBCs have a yellow
  color
• Green indicates old, retained secretions,
  proteolysis of mucopolysaccharides
• - if green and foul odor, usually a
  Pseudomonas infection
• Brown indicates old blood
• Red indicates fresh blood, blood streaked denotes
  tracheal or airway

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Sputum (contd)

• Sputum for C S
• Sputum for cytology