Microbiology Lecture 6

  1. Spinal Fluid
    • -clear fluid surrounding the brain and spinal cord
    • -Allows brain to “float” and reduces its weight
    • -Protects brain and spine from injury (impact)
    • -Normally clear, when infected with bacteria, can be yellow and turbid (bacterial meningitis)
    • -Can also get viral meningitis, but is usually less severe
  2. Bacterial Meningitis
    • -Can result in brain damage, hearing loss or learning disabilities
    • -Symptoms: high fever, headache, stiff neck, rash due to immune response (in newborns: head swelling, stop feeding, crankiness)
    • -Diagnosed by growing bacteria from a sample of spinal fluid
    • -Can be treated with antibioticsSpread through fluids (coughing, kissing, sneezing)
    • -Fatality is around 15% with treatment of antibiotics
    • -Vaccines are currently available against many types of meningococcal disease (recommended for college-aged students)
  3. Inhalation
    • -Infectious droplets from cough, sneeze, etc.
    • -Ex: Flu, TB, colds
  4. Ingestion
    • -Germs get on your hands, then on food, skin, etc.
    • -Unwashed produce, contaminated meat, etc.
    • -Ex: Salmonella, E. coli
  5. Direct Contact
    • -Spread directly from one person to another
    • -Ex: HIV, gonorrhoea
  6. Indirect Contact
    • -Spread via fomites (inanimate objects harboring germs)
    • -Ex: tissues, doorknobs, toilets, phones
  7. Animal Vectored
    • -Transmission through insect bite (flea, tick, mosquito, etc.)
    • -Ex: Malaria, Lyme disease
  8. Normal Flora
    • – normal microbial growth found in healthy person
    • -Usually found in GI tract, mouth, skin, upper respiratory tract
    • -Aide in digestion of food, vitamin production, protection from pathogens
    • -Can cause disease if invading normally sterile area
    • -Ex: E. coli and other bacteria in gut (>2 lbs!)
  9. Opportunistic Pathogen
    • – normally harmless bacteria that cause disease when host immunity is lowered
    • -Ex: C. albicans infections
  10. Virulent Bacteria
    • -growth occurs at expense of host
    • -Occurrence of disease determined by bacterial strain, inoculation size, site of entry & host factors
  11. Bacterial Entry
    • -Must get through natural barriers
    • -usually through tear in skin, tumor or ulcer in bowel
    • -S. aureus & S. epidermidis (normal skin flora) cause problems with catheters and IVs
    • -Can enter through natural openings (mouth, nose, ears, eyes, urogenital tract, anus)
    • -Protected by mucus & ciliated epithelium, antibacterial secretions in tears & mucus, acid & bile in GI tract
    • -Can then travel through bloodstream to other sites in body
Card Set
Microbiology Lecture 6
GUMicrobiology Lecture 6 Vocab