Transcript Microbiology DENT 132: E

Microbiology
– Study of Nature, Life, and Microorganisms
– Remember Microbiology is an important
part of Infection Control….. WHY?
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Microorganism
– Small Organisms Needing Microscope
– Adult Mouth
– http://en.wikipedia.org/wiki/Oral_ecology
– http://www.webmd.com/oral-health/healthymouth-14/your-healthy-mouth/rm-quizgerms-your-mouth
How many bacteria live in my
mouth?
– Between 100 Million & 20 Billion Bacteria
live in the mouth – produce every 5 hours
– All Microorganisms live in the mouth
– Need Microorganisms to live (ie. Bacteria
in Stomach, Yeast, Molds, etc.)
Microbiology
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www.rdhmag.com/articles/.../oralbacteria-how-many-how-fast.html
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Most Dangerous Are: Spores, Hepatitis
B, and Tuberculosis
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Aerobe (aerobic)
– Bacteria That Needs Oxygen to Grow…Will
Die Without It
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Anaerobe (anaerobic)
– Bacteria That Needs NO Oxygen to
Grow..Dies With It
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Hydrogen Peroxide Kills Bacteria—
Oxygenated Water
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Epidemiology
– Study of the Way Diseases Spread
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Etiology
– Study of the Cause of Disease
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Idiopathic
– Unknown Cause of Disease
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4 Major Types of Microorganisms:
– 1. Bacteria
– 2. Rickettsiae
– 3. Virus
– 4. Fungus
– See folder
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1. Bacteria
– 1 Celled Plant/Animal W/ No Chlorophyll
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Shapes/Forms of Bacteria:
– 1. Cocci – Spherical
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A. Monococci – Single
B. Diplococci – Pair
C. Staphylococci – Clusters
D. Streptococci – Chain
– 2. Bacilli – Rod-Shaped
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Lactobacilli: Most Common Bacteria in
the Mouth
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2 Types of Bacteria:
– 1. Spores
• Most Resistant
• Non-Growing, Protective
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Capsulated Spores Con’t
 Heavy Cell-Covering: Protective Mucoid
Covering on Bacteria
 Spores can remain dormant until opportunity
to infect (latent TB) (may never infect)
 TB infects the susceptible host (usually
person who comes in contact with TB spores
from a person with active TB and/or “high
risk” individuals)
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2. Spirochetes
Characteristics of Bacteria & Protozoa
Actively Motile, Flexible, Slender, Spiral
Found in Contaminated Water, Sewage, Soil
(They Love Moisture)
Passed Directly From Human to Human
Can Live Outside the Body
Killed by Penicillin & Drying
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Exotoxin
– Toxic Chemicals Secreted by Bacteria Such As
Tetanus, Botulism, Diptheria
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7 Diseases Caused by Bacteria
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Decay – strep & lactobacillus
Periodontal Disease – see next slide
Diptheria - Corynebacterium diphtheriae
Tuberculosis – tubercle bacillus
Typhoid Fever – salmonella bacteria
Pneumonia – bacteria (strep) & viruses
Syphilis – treponema pallidum
Bacteria associated with
Periodontal Disease
Actinobacillus (A.)
actinomycetemcomitans
 Porphyromonas (P.) gingivalis.
 Streptococci
 T. forsythia and T. denticola
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II. Rickettsia(e)
– Similar to Bacteria & Viruses
– Small
– Non-Motile
– Do Not Form Spores
– Don’t Live Outside Living Tissues
– Parasite Found in Insect Intestinal tracts
(ie., lice, ticks, fleas, mosquitoes)
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2 Diseases Caused by Rickettsiae
(transmitted by bite or rubbing into
tissue)
– 1. Typhus – fleas & ticks
– 2. Rocky Mountain Fever - ticks
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III. Viruses
– Smallest Microbes
– Infectious Particles, Like Small Parasites
– Only Seen by Electron Microscope
– Can Pass Through Filters That Catch
Bacteria
– They Don’t Live Outside Body & Cannot
Reproduce Outside Living Cells
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Shapes of Viruses:
– 1. Round
– 2. Elongated, With or Without Tail
11 Diseases Caused by Viruses
– 1. Colds
– 2. Smallpox
– 3. Measles
– 4.Mumps (parotid gland)
– 5.Rabies – virus found in saliva
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6. Chicken Pox
7. Herpes Simplex
8. Flu
9. Polio
10. Hepatitis
11. HIV
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– AIDS = Acquired Immune Deficiency
Syndrome
– HIV – Human Immunodificiency Virus
– What’s the difference?
Function of the Liver
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Function of the Liver is to Metabolize
Fats, Detoxify Harmful Substances, &
Produce Body Heat
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A. Hepatitis A – Infectious
 Can Survive for Weeks on Dry Surface
 Hepatitis Can Withstand Alcohol, Boiling
Water, and Most Disinfecting Solutions
 B. Hepatitis B – Serum
 Caused by Needles, Dirty Instruments,
Blood, and Saliva
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Vaccine Available for Hep B:
Response:
 #1 (0) Month
 #2 (1 Month Later)
 #3 (6 Months Later)
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30%
75%
96%
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One Month After #3, Test for Antibodies
 Every 2-5 Years, Get Tested
 Booster May be Needed 7 Years +
 Can Be Non-Responder (have 2 tests,
then wait)
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C. Non-A Non-B (Like Hepatitis B)
– Same Transmission & Carrier State
– No Vaccine Available
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CDC Policy, If Needle Stick, Test:
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1. Immediately
2. 6 Weeks Post-Exposure
3. 12 Week Post-Exposure
4. 6 Months Post Exposure
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D. Hepatitis D – No Vaccine Available
 E. Cirrhosis of the Liver
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– Non-Viral
– Considered Hepatitis
– Not Inflammatory
– Chronic, NOT Reversible, Progressive
– Liver Hardens as it Deteriorates
– Not Contagious
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Diagnostic Tests Performed
– A. Elisa (to screen blood)
– B. Western Blot Assay (to screen blood)
– C. HIV Antigen Assay
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IV. Fungus/Fungi
– Plants that Lack Chlorophyll (yeasts/molds)
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More Than 100,000 Types, in 2
Categories:
 1. Yeasts
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• 20-100 times larger than bacteria
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2. Molds
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Makes Penicillin
Mold if Wooly or Furry
Mildew on Spoiled Foods, Clothing, Walls
Used in Cheese and Salad Dressing
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Thrush
Athlete’s Foot
Ringworm
If Fungi is Food, It Is Edible Because It Comes
From Living Organism, Like Mushrooms
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Protozoa
1-Celled Microorganism/Animal.
Simplest Form of Animal Life
If Pathogenic, Transmitted by Carriers, Like
Malaria
Malaria – Chloroquinine to Prevent
Needs Fluids to be Active (pools, lakes)
Mostly Aerobic (needs oxygen)
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Why Can’t You Tell That You’re
Spreading A Disease?
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Rich Blood Supply in Mouth- helps
speed up healing