Test 1 Flashcards
Branches of Microbiology
Bacteriology Virology Protozoology Mycology Phycology
Gram+
Violet Stain @ alcohol wash
Gram-
Release exotoxins
Acid
Fast stain / retain a red carbolfuchsin stain @ acid wash
Sporeform bacteria
Clostridium Tetani
Clostridium perfringens
Clostridium botulinum
Streptococcus Pneumonia
Alpha Hemolytic Facultative anaerobe Occurs singly, pairs, short chains accounts for 30-40% of community acquired pneumonia Type III is most common and virulent Also responsible for: infectious bronchitis peritonitis meningitis otitis media (inflam of middle ear)
Klebcella pneumonia
Friedlanders bacillus
non-motile
facultative anaerobic
Opportunistic, frequently in upper airway
Causes Pneumonia in alcoholic and COPD pt’s
Causes severe necrotizing pneumonia, may cause septicemia
Sputum is described as red current jelly
Escherinchia Coli (Ecoli)
In normal flora of intestinal tract Causes: Urinary tract infections pneumonia neonatal meningitis septicemia in debilitated hosts
Pseudomonas aueruginosa
Aerobic bacillus causes opportunistic infections frequent contaminant of aqueous solutions causes pneumonia and sepsis Associated with VAP
Legionella pneumophilia
Atypical bacteria
very difficult to identify
appears to colonize water
causes a atypical pneumonia
transmitted via direct inhalation or aerosol
not thought o be trans from person-person
Microbacterium tuberculosis
Non-Motile Non-spore forming Small highly aerobic bacilli Causes chronic granulomatous pulmonary infections trans via droplet and droplet nuclei
Cocci
Spherical shape
Bacilli
Rod-like shape
Spirochetes
Helical or spiral
Staphylococcus aureus
Facultative anaerobe
Normal flora of skin & upper AW
Common cause of skin disorders
MRSA - Resistant to antibiotics
Pneumonia causing in very old/young or debilitated
Exotoxins result in extensive tissue necrosis
Predisposing factors of anearobic lung infections
decreased level of consciousness
impaired swallowing
gastrointestinal dysfunction
Anaerobic Pneumonia
Usually multimicrobial
Influenza Virus
Three major types A-C
A&B are resp for increase in resp infections
Type B resp annual flu epicemics
RhinoVirus
Accounts for %40 all acute resp illness
Enteroviruses
Coxsackie
Polio
3 elements for infection to spread
A source of pathogens
A susceptible host
A route of transmission
Contact routes
Direct - Direct phys contact
indirect - cont. btw susceptible host & contaminated object
Droplet - Cough or sneeze
Vehicle Route
Food
Water
Airborne route
Aerosols - Legionellosis
Droplet nuclei - Tuberculosis
Dust - Histoplasmosis
Vectorborne Route
Ticks - lyme’s disease
Mosquitos - malaria
fleas - bubonic plague
Spread of infection into lung 3 mechanisms
Aspiration of oropharyngeal secretions
Inhalation of aerosol droplets
(droplet nuclei/dust particles)
Blood-borne spread - from another site of infection
Infection control methods
Cleaning Disinfection Sterilization Disrupting routes of transmission decrease host susceptability
Sanitation
Cleansing to decrease microbe concentrations to a safe level
Disinfection
Freeing from infection - The destruction of potentially pathogenic organisms. Doesn’t kill spores.
Types of Clean technique
Asepsis
Antisepsis
Asepsis
The state of being free from pathogenic organisms or a description of techniques that prevent sepsis
Antisepsis
The application of chemicals to body surfaces that inhibit the growth and multiplication of pathogenic organisms
Elimination techniques of pathogens
Aseptic technique - ster/disinfect of equip
Bactericides - kill bacteria
Germicides - kill germs
Sporicide - Kills spores
Bacteriostatic - elim ability to reproduce
Sterilization
Complete destruction of all microorganisms. Includes vegetative cells and spores. Either physical or chemical agents ar eused to end metabolic activity permanently
Ethyleneoxide
More effective in H2O vapor
humidity between %30-70 maintain
above 60 degrees C polymerization occurs and steriliztation DOESNT take place
Gas is highly diffusable, Penetrates well, and effective at ambient temperatures
Explosive at concentrations > 3.0%
Used w/ 10% concentrations with CO2 or freon to Decrease explosiveness
Leaves a residue on porous material / Harmful to human tissue
H20 droplets can interfere with sterilization and form ethylene glycol / sticky
Equip must be prepackaged due to permeability of gas, wrapping material must be permeable
Indicator Tape
Used to indicate appropriate exposure to ETO but DOESNT guarantee sterility
Gluteraldehydes - Acid / Alkaline
2% Gluteraldehyde / 8% formaldehyde in 70% alcohol either acid or buffered to an alkaline solution
Destroys cell by attacking lipoproteins in the cell wall or cytoplasm
broadly bacteriocidal, kills gram-/+, spores, M-TB, and viruses
Used in adequate doses and long periods of time
Very irritating to skin and mucosa
Equipment must be clean, it penetrates dirt poorly.
Pasteurization
Submergence of equipment in medium hot water for specific periods of time
30 mins @ 70 degrees C
Kills vegetative bacteria but not spores
Effect on viruses varies
Mechanism of action is to coagulate proteins
Large Volume Nebulizers
Fill with sterile H20
DO NOT add fluid to partially filled resevoir
Drain condensate away from PT.
Discard contaminated waste
Do not allow condensate to drain back into resevoir
Sterilize or high-level disinfect BTW Pt’s and every 24 hours.
Small Volume Nebulizers
Disinfect BTW pt’s, rinse w/ sterile water and air dry
use single unit dose vials and despense aseptically
BTW Pt’s replace w/ sterile or high-level disinfected units.
02 equipment
Use pre-filled disposable humidifiers
Re-usable humidifiers should be refilled with sterile H20 before use
Before refilling drain and rinse humidifier before filling with sterile H20
Chlamydophila pneumonia
Obligate intracellular bacteria
WBC normal, NPC, mild fever
Atypical pneumonia
Chlamydiae psittaci - psittacosis (ornithosis)
increasing evidence its assoc elev asthma exacerbations
Acinetobacter baumannii
Aerobic Bacillus Causes opportunistic infections frequent contaminant of aqueous solutions causes pneumonia and sepsis assoc with VAP
Mycoplasma pneumonia
Small cell-wall deficient (no cell wall)
WBC normal, NPC, fever
Atypical pneumonia
freq in young adults late summer/early fall
College kids and military
uncommon after age 50
resp for 10-50% of pneumonia in college students and military
Rickettsiae
Extremely infectious
intracellular parasites
Several pathogenic members:
- Rocky Mtn spotted Fever
- Rickettsia Burnetii - Q fever
Transmitted by vectors, sheep, cattle, catsViruses
Submicroscopic
noncellular
parasitic particles composed of a protein shell and a nucleic acid core
Fungal Resp infections
Histoplasmosis Bastomycosis Coccidioidomycosis Cryptococcosis Aspergillosis Candidiasis
Pneumocystis jiroveci
PCP - Pneumocystis carinii pneumonia
assoc with first decade of AIDS
Common in indiv w/ weakend immune systems.
ARDS
Acute Respiratory Disease Syndrome
General Mechanisms of Action - Eliminating source of pathogens
Denaturation of protein
Coagulation of protein
Decrease surface tension
Interference with intracellular metabolic pathways
Denaturation of protein
Chemical alteration of protein structure causing it to lose some or all of it’s characteristics.
Coagulation of protein
Solidification into a gelatinous mass
Decrease plasma Surface Tension
Decrease plasma surface tension
Increase plasma membrane permeability
Allows an influx of fluid that lyses the cell
Dry heat sterilization
Less effective as moist heat, requires longer exposure times
Does not dull sharp metal edges
usually reserved for glass and metals
Dry heat sterilization times
60 min @ 170 C
120 min @ 160 C
150 min @ 150 C
Physical Sterilization methods
Heat - denature proteins
Incineration
Autoclave
Gamma irradiation
Autoclave
High Temperature by using steam at 15 psig
Moisture increases the conduction of heat and rate of killing
All the air must be removed and replaced with steam.
Chemical Sterilization methods
Gas Sterilization - EthyleneOxide
Gluteraldehyde - Acid or alkaline
Physical Disinfection methods
Pasteurization
Chemical Disinfection methods
Gluteraldehydes - same as sterilization but less time 10-20 min
Alcohols
Phenols
damage cell walls, denature proteins, inactivate enzymes
Eff against bacteria and fungi
activity against virus and spores varies
remains eff on surfaces after application
irritating to skin
Halogens (sodium hypochlorite) Known as Bleach potent and rapid acting disinfectant 1/100 dillution Bactericidal in 10 min Fungicidal in 1 hour Virucidal in 10 min (inc HIV and HBV) 1/10 dillution is recommended for blood
Halogens (Iodine)
Tincture of iodine (iodine in alcohol)
Bactericidal, fungicidal, virucidal, and sporicidal
Cause tissue necrosis in high concentrations
Stains
Iodophors - Water soluble, non-staining, and less irritating to tissue. Limited sporicidal activity and requires prolonged contact to kill fungi.
Quaternary ammonium compounds
Nontoxic and inexpensive
Destroys membranes and inactivate enzymes
Detergents containing ammonium ions
Effective against gram+ but gram- varies
Most common use is surface disinfectant
Neutralized by anionic detergents, dirt and organic materials
Acetic acid - White Vinegar 1/3 dillution for use.
it’s PH of 2.0-3.0 inactivates cellular enzymes
More effective against pseudomonas aeruginosa
Alcohol chem disinfection
With Increase in carbon chain length there is an increase in bactericidal activity (denatures proteins)
Kills most bacteria and fungi inc. M TB
Activity against viruses varies
Ethyl alcohol is best viricide
Isopropyl works best in 90% solution
Ethyl works best in 70% solution
Kills Hep B in 15 min
Kills HIV in 1 min
Acetic acid
White Vinegar 1/3 dillution for use.
it’s PH of 2.0-3.0 inactivates cellular enzymes
More effective against pseudomonas aeruginosa
Quaternary ammonium compounds
Nontoxic and inexpensive
Destroys membranes and inactivate enzymes
Detergents containing ammonium ions
Effective against gram+ but gram- varies
Most common use is surface disinfectant
Neutralized by anionic detergents, dirt and organic materials
Halogens (Iodine)
Tincture of iodine (iodine in alcohol)
Bactericidal, fungicidal, virucidal, and sporicidal
Cause tissue necrosis in high concentrations
Stains
Iodophors - Water soluble, non-staining, and less irritating to tissue. Limited sporicidal activity and requires prolonged contact to kill fungi.
Halogens (sodium hypochlorite)
Known as Bleach potent and rapid acting disinfectant 1/100 dillution Bactericidal in 10 min Fungicidal in 1 hour Virucidal in 10 min (inc HIV and HBV) 1/10 dillution is recommended for blood
Phenols
damage cell walls, denature proteins, inactivate enzymes
Eff against bacteria and fungi
activity against virus and spores varies
remains eff on surfaces after application
irritating to skin
