Infection vs Colonization

  1. SUPERorganism?
    • Humans are SUPERorganisms/Ecosystems:
    • We have HUMAN CELLS
    • and Viruses, Fungi, Protozoas, and Bacteria (MOSTLY)
  2. How many species live within and on us?
    • about 501 species/orgnaism:
    • 1 species of Human: 10 trillion human cells
    • 500 species of bacteria:100 trilion bacerials cells
  3. 2-3 lbs of bacterial cells

    Mouth=billions of bacertial cells
    Skin= 10x more than mouth
    GI= 1000x more than mouth
  4. Locations of Normal Flora

  5. Locations of Normal Flora

    G.I. Tract
    • Oropharynx- HIGH
    • Stomach- Low (b/c of stomach acids)
    • Small Intestine- Medium
    • Large Intestine- HIGH

    ** HIGH because open to enviroment (TOP and BOTTOM)***
  6. Locations of Normal Flora

    Respiratory tract
    • Oropharynx: HIGH
    • Lungs: NONE (should be sterile)
  7. Locations of Normal Flora

    Fermale Reproductive Tract
    • Vaginal Canal: High
    • Uterus: None
  8. Locations of Normal Flora

    Urinary Tract
    • Urethra: Low
    • Bladder: None
  9. Locations of Normal Flora

    Nervous, Bone and Muscle... SHOULD BE STERILE!!!
  10. Why are UTIs, respiratory infections and middle ear infections so common?
    • UTI- opening to the bladder (urethra) are so close to dirty regions
    • Respiratory infections- Close to a dirty region... oropharynx
    • Ear infections- Eustation tube (tube that connects the middle ear to oropharynx)
  11. SYMBIOSIS- Living Together

    • Normal flora:
    • Commensalism: micro benefits, host is unharmed (ex. some microbes on skins are harmless, nonbeneficial
    • Normal/beneficial flora
    • Mutualism: microbe and host benefit (ex. some microbes in intestinne assist with Vitamin K)
  12. Symbosis: Living Together

    • Normal/Harmful Flora (aka OPPORTNISTIC pathogens)- normal flora turns pathogenic (ex. some microbes in mouth can cause cavities)
    • Exogenous Pathogens (usually require "exposure");
    • ----Parasitism: microbes benefits, host is harmed (most viruses)
  13. Microbe benefits, host is unharmed:

    A. Commensalism
  14. Microbe benefits, host is harmed

    C. Parasitism
  15. Some microbes in intestines assist with vitamin K is an example of....
    Mutualism (BOTH mutual... BENEFIT)
  16. An example of opportunistic pathogen:
    Some microbes in the mouth can cause cavities
  17. Sources of Healthy Flora

    Fetal vs. Adult Intestions
    • Fetal: 100% have NOOOOOO bacteria (sterile)
    • Adult: 100% HAAAVVVE bacteria in LARGE amounts
  18. Sources of Healthy Flora:

    • Vaginal cana- Lactobacillus (increase during pregnancy)
    • Hands- Lactobacillus, E.Coli, Bifidobacteria
    • Nipples- Bifidobacteria
    • Mothers's mouth- Streptococi, Neisseria
    • Everyone else
    • Normal flora in 1-2 years
  19. Diversity of Normal Flora:
    -Diversity w/ different locations: Bacteria adapted for specific areas(via receptors, nutrients, pH)
    -Diversity w/ different ages: Bacteria change throughout lifetime (due to exposure, hormones, diet, lifestyle)
    -Diversity w different individual: Not eveyone has same flora (due to genes, gender, race, polymorphisms)
  20. Benefits of Flora:
    • -Inhibit invasion by pathogens: Compete for attachment sites, Create non-optimal pH
    • -Inhibit colonization by pathogens: Compete for nutrients, Secrete bacteriocidal/static substances (keeps it from replicating)
    • -Sources of vitamins- Some synthesize vitamin B and K
  21. LOOOOVE your flora!
    - Animal experiments:
    w/ flora: can take 1 million salmonella bacteria to kill it
    w/out flora: can take 10 salmonella bacteria to kill it
    W/out flora: would be dead in 2 weeks if all flora removed.
  22. How long would it take for us to die without flora?
    2 weeks
  23. Altering Infant Flora

    -C-Section (vs. Vaginal Delivery)
    • Vaginal delivery born have lower risk of asthma
    • C-section born fecal bacteria:
    • Lactobacillus lower until day 10
    • Bifidobacteria lower until day 30
    • B fragilis lower until day 180
  24. Which of the following is lower until day 180 in children born from c-section delivery?

    A. B. Fragilis
  25. Which of the following is lower until day 10 in children born from c-section delivery?

    B. Lactobacillus
  26. Which of the following is lower until day 30 in children born from c-section delivery?

    A. Bifidobacteria
  27. Altering Infant Flora:

    Breastmilk vs. Formula
    • Breastmilk-fed tend to have better health
    • Nipples have flora not in formula
    • Breastmilk has nutrients/compounds not in formula- so gut bacteria may adjust to nutrition source
  28. Altering Adult Flora; Dangers of Cleanliness

    • 20% of users will develop antibiotic-associated diarrhea
    • Increased risk of intestinal bacterial infection by clostridium difficile
  29. Antibiotics increase risk of intestinal bacterial infection by ________________

    A. Clostridium difficile
  30. Altering Adult Flora: Dangers of Cleanliness

    • Cancer patients that use mouthwash have an increased mucositis (inflamation of mucous membranes of G.I. Tract)
    • -Because they are immune suppressed and the mouth is a reservoir for healthy flora, so if you kill it all there is a chance that bacteria can get in.
  31. Altering Adult Flora: Dangers of Cleanliness

    • Women who douche have higher rates of :
    • Vaginal irritation, vaginal infections and uterine infections
  32. The Hygiene Hypothesis
    Immune systems aren't being challenged by disease and dirt early in life, so the body's natural defenses overreact to small irritants such as pollen
  33. Hygiene Hypothesis

    Support (-Relationship of environment to immune reactions)
    • Wild mice/rats=very dirty environment (very mild immune reactions -4X more antibodies than lab rodents)
    • Lab mice/rats= Dirty environment (mild immune reactions... nibble on turds<--- good thing )
    • Average Human= Sorta dirty enviroment- (medium immune reactions)
    • Some Humans= Less Dirty Enviroment(strong immune reactions.. asthma , allergies)

    SO BOTTOM LINE: too clean/dirty is BAD
  34. Hygiene Hypothesis

    Humans are less likely to have asthma if as a child, you:
    • Born by vaginal delivery (rather than c-section)
    • Had more siblings or pets
    • Entered day care in your first year
  35. Infection:
    1. Adherence
    2. Invasion
    3. Evasion
  36. Infection:

    • Attaches to host biomolecule ("receptor")
    • - anything outside of the cell can be used as a receptor ie. protein, crbohydrate, lipid
  37. Infection:

    • May release enzymes to:
    • Degrade "cement" between cells: ex: secrete enzymes such as collagenase, hyaluronidase
    • Decrease clotting of blood: (Imporatant mechanism to clot and seal off -containment) ex. Streptokinase (from streptococci) , Staphylokinase (from staphylococci)
    • Lyse with white blood cells: ex. Phospholipases
    • Increase clotting of blood ( to trap WBC in and they could invade)- ex. Coagulase
  38. Which of the following enzyme(s) degrade "cement" between cells:
    1. Collagenase
    2. Hyaluronidase
    3. Coagulase
    4. Phospholipases
    5. Staphylokinase
    • 1. Collagenase
    • 2. Hyaluronidase
  39. Which of the following enzyme(s) lyse white blood cells:
    1. Collagenase
    2. Hyaluronidase
    3. Coagulase
    4. Phospholipases
    5. Staphylokinase
  40. 4. Phospholipases
  41. Which of the following enzyme(s) increase clotting of blood
    1. Collagenase
    2. Hyaluronidase
    3. Coagulase
    4. Phospholipases
    5. Staphylokinase
    3. Coagulase
  42. Which of the following enzyme(s) decrease clotting of blood
    1. Collagenase
    2. Steptokinase
    3. Coagulase
    4. Phospholipases
    5. Staphylokinase
    • 2. Steptokinase
    • 5. Staphylokinase
  43. Infection:

    Escape and/or survive phagocytosis by WBCs
  44. Infection:

    Toxigenesis (stimulate inflammation in body)
    • Seccrete exotoxin (created by bacteria)
    • Release endotoxin (piece of bacteria_
  45. Infection:

    "Obligate" pathogen
    • Need host to reproduce:
    • Viruses: all
    • Bacteria (some: Chlamydia, rickettsia
    • Prozoan: plasmodium
  46. Virulence
    The relative ability of a pathogen to cause infection or disease

    • High virulence (infectivity)- a samll amount can easily overcome defenses
    • High virulence (mobidity): a pathogen that stongly compromises health
  47. High Virulence (MOBIDITY)- extremely dangerous ... higher chance of mortality
    • Anthrax, ebola, marsburg, mad cow prion
    • Highly virulent pathogens are not that common because they kill their host early and can't spread... burn themselves out.
  48. Diminishing Virulence (morbidity)
    Syphilis first appread in the 1400s and would kill its host but now it has mutated into a less virulent form which benefits it
  49. Strategic Virulence (morbidity)
    • Symptomatic: Cough, sneeze, diarrhea, open sores (Benefits both the species and the microbe)
    • Asymptomatic: NO real signs of infection: HPV 50% of all sexually active women will aquire it, only 1% will show "warts"
  50. Sources of Infection:

    Endogenous= opportunistic pathogens (b/c coming from within our body)
    • Compromised health- already sick, sleep-deprived, stress (high cortisol), Medications that decrease defenses ie glucocorticosteroids
    • Compromised barriers: Cuts, burns catheters
  51. Sources of Infection

    Exogenous: Transmitted pathogens
    • Exposure + compromised health/barriers
    • Exposure to High concentration
    • Exposure to HIgh virulence (infectivity)
  52. Endogenous: Opportunisitc Pathogens

    Normal Flora turns pathogenic:
    increased concentration in normal location
    presence in abnormal location
    • Mouth- Increased concentration (due to sugar) Streptococcus mutans cause caries/cavities
    • Pharynx- Abnormal Location (lungs) of Streptococcus pneumoniae cause pneumonia,
    • Abnormal location (brain membranes) of Neisseria meningitidis cause meningitis
    • Lower intestine: Abnormal ocation (peritoneal cavity) of Bacteriodes cause peritoneal infection
    • Abnormal location (urethra) of E. Coli cause UTI
  53. Which of the following cause cavities?

    D. Streptococcus mutans
  54. Which of the following cause peritoneal infection?

    E. Baceriodes
  55. Which of the following cause UTIs when found in the urethra?

    C. E. Coli
  56. Exogenous: Transmission
    • Communicable Disease (ex. cold)- From human to human: air, fluid, solid.... Contagious- easily transmittable
    • Zoonotic disease (ex. rabies)- From animal to human: teeth and beaks... dogs, birds, rodents reptiles, sheep
    • Vector Disease (ex. malaria)- From insect to human: bugs and bites... flies, fleas, lice, ticks, mites
    • Food/Water-borne disease (ex. salmonella)- From food and/or water (salmonella= chicken eggs)
  57. Easily Transmittable
  58. Tranmission from animal to human
    Zoonotic (ex. rabies)
  59. Tranmission from insect to human
    Vector disease (ex. malaria)
  60. How is infection acquired?
    • Community acquired- any disease acquried OUTSIDE a healthcare facility
    • Nosocomial or Hospital aquired or latrogenic; disease acquired INSIDE a healthcare facility
  61. Nosocomial or Hospital-acquired or latrogenic:

    Disease acquired INSIDE a healthcare facility

    Common problem because:
    • High Concentration of sick people
    • Spread by healthcare professionals
    • Lots of open wounds or intubations
    • Most are drug resistant infections (70%)
  62. Nosocomial or Hospital-acquired or latrogenic:

    Most susceptible patients
    • Surgical, burn, obstetrics (ALL have open wounds)
    • Preemies, elderly (compromised immune system... do not have strong defenses)
    • Diabetic, cancer, on glucocorticoid treatment (compromised immune system/ health allowing things to settle in)
  63. Nosocomial infections

    Most common infection sites/types:
    • 1. Urethra: Urinary Tract Infections-UTIs (33%) (b/c of catheters)
    • 2. Wound: Surgeica wound Infection (17%)
    • 3. Lungs: Lower RTI (pneumonia) (15%) inhaling other microbes
    • 4. Blood: Septicemia (14%)
  64. "sp" or "spp" after a microbe name means.....
    species (singular or plural)
  65. MOST common infection pathogens (nosocomial infections)
    • 34% caused by these 3 gram-positive cocci:
    • -Staphylococcus aureus, Enterococcus spp, Coagulase-negative staphylococcus
    • 32% caused by these 4 gram-negative bacilli:
    • -E.coli, Enterobacter spp, Klebsiella spp, Pseudomonas aeruginosa
  66. Most common BACTERIA infections in U.S.
    • Genital chlmydia
    • Gonorrhhea
    • Slmonellosis
    • Syphilis
    • WHoooping cough
    • Tuberculosis
    • Lyme disase
  67. Most common VIRUS infections in U.S.
    • HPV
    • Herpes
    • Hepatitis A, B, C
    • AIDS
    • Chickenpox
  68. Most common Protozoa infections in U.S.
    • Tichomoniasis
    • Giardiasis
  69. Most common Fungal infections in U.S.
    Tinea- Ringworm, athlete's foot, jock itch
  70. Frequency of a disease
    Morbidity rate
  71. Frequency of death
    Mortality fate (death rate)
  72. Occurs occasionally
    Sporadic diease
  73. Always present
    Endemic Disease
  74. Sudden/Rare local outbreak
    Epidemic disease
  75. Sudden/Rare Global Outbreak
    Pandemic Disease
  76. Stress releases what hormone that increases your rate of infection?
    Glucocorticosteroid (high cortisol)- depresses WBC
  77. What is PNEUMONIA caused by... bacteria, virus, protozoa, fungal?
    could be ANY (only know if cultured)
Card Set
Infection vs Colonization
IBHS Exam 3 Dr. Richard's Lecture: Infection vs Colonization