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Author: Amelia Virostko

1. Common infection pathway

  1. Encounter
    1. Exogenous, endogenous, or nosocomial
  2. Entry - ability to colonize within host
    1. Ingestion, inhalation, cutaneous, insect vectors, colonization factors
  3. Spread - local or move to another tissue site
  4. Multiplication
  5. Damage
  6. Outcome

2. Bacterial Groups

  1. A. single-cell prokaryotes
  2. Gram stain - based on cell wall structure
  3. Gram positive has thick peptidoglycan cell wall
    1. Cocci
      1. Streptococci
      2. Staphylococci
    2. Rods - straight or curved
      1. Mostly anaerobes
      2. Clostridium
  4. Gram negative has thin cell wall and outer lipid bilayer with lipopolysaccharide
    1. Cocci
      1. Meningococci
      2. Gonococci
    2. Rods
      1. Enterics
      2. Fastidious organisms
      3. Haemophilus
      4. Bordetella
      5. Campylobacter
      6. Helicobacter
  5. Spirochetes
  6. Acid Fast
    1. Mycobacteria stain with acid fast

3. Protozoans

  1. Unicellular eukaryotes
  2. At least part of life cycle in host

4. Helmiths

  1. Multicellular eukaryotic worms

5. Fungi

  1. Free-living eukaryotes
  2. Dimorphic growth

6. Viruses

  1. Unable to replicate outside host (obligate intracellular parasites)