Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Microbiology
Final Exam Review
| Question | Answer |
|---|---|
| List organisms in order of resistance: Enveloped viruses, vegetative bacterial cell, non-enveloped virus, vegetative Fungi, Mycobacteria, Bacterial endospores, Fungal spores | Bacterial Endospores Mycobacteria Fungal Spores Non-Enveloped Viruses Vegetative Fungi Enveloped Viruses Vegetative Bacterial Cell |
| Characterized by: abnormal pathogenic agent, neurodegenerative disorders, able to induce abnormal folding of specific normal cellular proteins, transmissible, rapidly progressive, always fatal, long incubation period, spongiform changes | Prions |
| A virus of important cause of upper respiratory infection and oral disease in cats. Symptoms: sneezing, nasal congestion, conjunctivitis, discharge from eyes and nose. (ulcers in mouth) Can cause painful lameness. Indirect and direct transmission. | Calici virus (non-enveloped virus) |
| Feline Herpesvirus (FHV) (enveloped) | A virus that causes acute upper respiratory infections (URIs), although it has been associated with some other diseases. The virus is readily transmitted between cats through: Direct contact – through contact with saliva, ocular or nasal secretions. |
| Polymerase chain reaction (PCR) | Amplifies DNA so that one copy becomes millions of copies in a matter of hours. This is useful to detect and identify DNA where small amounts are present. |
| One of the most common infectious diseases in cats. Virus shed in saliva, nasal seepage, urine, feces, and milk. Bite wounds or mutual grooming. Rarely, litter boxes and dishes. Common cause of cancer. Causes various blood disorders and immune deficiency | FeLV - Feline Leukemia (enveloped virus) (gingivitis and stomatitis seen in infected cats |
| Highly contagious respiratory illness with persistant dry cough, Fever, Nasal discharge, Sneezing, Eye inflammation, Lethargy, Loss of appetite in dogs. Potential complication: pneumonia. It is transmitted by contact with infected secretions or aerosols. | Parainfluenza (Kennel Cough) (enveloped virus) |
| Highly contagious viral infection in dogs. Two forms: intestinal, characterized by vomiting, bloody diarrhea, weight loss, and lack of appetite (anorexia), cardiac: attacks heart muscles of fetuses and very young puppies. Often fatal. | Parvovirus (puppies 6 wks - 6 months most commonly affected) non-enveloped virus |
| What is the name for acute, progressive encephalomyelitis caused by lyssaviruses? Signs: acute behavior changes and progressive paralysis. Dogs are the most important reservoir. Fatal once clinical signs appear in humans. Always fatal in animals. | Rabies (transmission through saliva) enveloped virus |
| How do viruses cause cancer? | Viral DNA is incorporated into cellular DNA (common in retroviruses) Continued viral expression (no off switch) Transforms proteins (mimics growth hormone). Transforms genes (cancer genes activated by a carcinogen) Uninhibited growth of abnormal cells. |
| How does the host fight viral invasion? | Release of Interferon (close and lock the doors and windows) Antibodies and Lymphocytes. Cell death or even host death. Chronic infection: viral genome becomes part of host cell DNA |
| Viruses multiply in a three step process: | Enter Cell (after recepter ID). Direct cell membrane fusion or endocytosis (inward budding). Entertainment: host cell does all the work of building new virus copies. Exit Cell: kill the cell and release with cell rupture or budding from cell membrane |
| A complete infective virus particle is called a: | virion |
| Some virus types have lipid wrap around nucleocapsid. This wrap is called an: | envelope |
| Capsid + Nucleic acid = | nucleocapsid |
| Protein shell around nucleic acid core. Made of repeating structure units. | capsid |
| What do you call a set of genes (instructions in DNA or RNA) packaged in a virion (protein coat) | A virus (an obligate intracellular parasite incapable of self-replication. |
| Name seven ways to contract a virus. | Aerosols, Direct contact, Asymptomatic carriers, Contaminated food, water, surfaces (fomites), Arthropods, Iatrogenic (DVM, Medication, Therapy induced), Endogenous (growing or originating from within an organism |
| Name four methods used to diagnose Cryptococcus fungal infection. | Cytology (usually diagnostic) Prolific in tissues. Characteristic thick capsule when stained. India Ink or Cotton Blue. Serology, Antigen, Culture |
| How do you diagnose Malassezia yeast? | Tape prep, Direct cytology (Wright Stain or Dif-Quick) |
| Name a common cause of dermatitis in dogs. (esp. skin folds and ears of allergic dogs) No classic presentation for skin. Seborrhea (flaky skin and greasiness of the skin and hair) and pruritis are common. Secondary bacterial infections are not uncommon. | Malassezia yeast infection |
| Objects or materials which are likely to carry infection, such as clothes, utensils, and furniture | Fomites |
| Dermatophytes are a _______ risk. | Zoonotic - Especially to children. Cause damage to skin. Animals (esp. cats) can be asymptomatic carriers. Prevention is best. Wear gloves when handling suspect cases. Bleach all fomites. Prevent hunting of rodents. (they are carriers) |
| What is a DTM and how is it used? | Dermatophyte Test Medium. Selective and Differential. Only grows fungi and has a red color change in seven days, if positive. Most reliable test. Hairs should be plucked from edge of lesion after area has been cleaned with alcohol. |
| What is a test using Direct Microscope Evaluation for dermatophytes? | KOH, Prep specimen using Potassium (K) & Hydroxide (OH). Arthrospores grow on outside of hair shaft but cannot normally be seen. Pluck a few hairs from periphery of lesion. Place on slide with 1-2 drops 10% KOH solution add cover slip. Warm gently |
| How is a Wood's Lamp (black light) used to diagnose dermatophytes? | Flourescent hyphae in hair shaft. Only some strains of fungus will be positive. Lamp should be allowed to warm up for five minutes. |
| Traits of dermatophyte disease? | Fungi enter hair follicles by growing down hair shafts. Invades keratin. Arthrospores form as hair grows upward. Microsporum canis is one example. |
| Dermatophytes Fungi that invade hair, nails, and superficial layers of skin are called: | keratinophilic fungi symptoms: lesions-often pruritic and cause crusty skin and hair loss. "ringworm" Differ between species. Spores are hard to kill. |
| Disease common in birds, but can cause disease in any species. (German Shepards especially at risk). Severe nasal and sinus infections. Can cause pneumonia. Very difficult to treat in any species. | Aspergillus (conidia)(flower like growth of hyphae and spores |
| Fungi Imperfecta Medically important species include: | Dermatophytes: Microsporum, Trichophyton. Histoplasma, Candida, Aspergillus |
| Histoplasma | |
| Candida | |
| Microsporum | |
| Trichophyton | |
| Why are mushrooms medically important? | Toxicity if ingested. Symptoms: vomiting and diarrhea. Neurological signs. Liver or Kidney failure. Death. |
| Common symptoms of Coccidioides (Valley Fever) infection in dogs and cats? | Dogs: (chronic cough, anorexia, cachexia, lameness, enlarged joints, fever, intermittent diarrhea). Cats: (draining lesions, SQ granulomatous masses, abscesses, fever, weight loss) |
| Soil fungus (Ascomycetes) of Lower Sonoran Life Zone. San Joaquin Valley, CA (Valley Fever) and Arizona, Texas, Utah, Nevada, Mexico | Coccidioides |
| True or False: many of the systemic fungal pathogens are dimorphic. | True: They produce hyphae on environmental surfaces and yeast in animal tissue. |
| Having both a yeast and a mold form (mycelial). | Dimorphic |
| Fungus that have no hyphae and multiply by budding. | yeasts (examples: Malassezia & Cryptococcus) |
| Mycotic Terminology Asexual spores borne externally on hyphae (branches) Look like flowers. | conidia |
| Mycotic Terminology Asexual, thick-walled, spores formed by hyphal septation. Look like tapeworm. | arthrospores |
| Mycotic Terminology The intertwined mass of hyphae that forms the mold colony. | Mycelium |
| Mycotic Terminology A filament or branch from which the fungus grows. Tips can grow either from mitosis or meiosis; depending on the type of fungus. | Hyphae |
| What are five traits of parasitic or free-living fungus? | Most are multi-cellular (except yeasts), Eukaryotic, cell walls contain chitin, they do NOT contain Chlorophyll, they digest externally with enzymes and then bring nutrient molecules into cells. |
| What process destroys pathogens such as Mycobacterium tuberculosis and Salmonella typhi @ 63 degrees celsium for 30 seconds without altering the flavor? | Pastuerization (not sterilized) That is accomplished at higher temperatures for a shorter duration. |
| As long as the steam directly contacts the material to be sterilized, steam applied under pressure (121 degrees C for 15 minutes) is the most effective moist heat sterilization. What do you call this process? | Autoclaving |
| Boiling (100 degrees C @ sea level) kills vegetative cells and viruses within _____ _____ | 10 minutes |
| How does moist-heat kill microbes? | Denaturing enzymes (coagulation of proteins) |
| Drying out of living organism. Microorganisms cannot grow and divide when ________, but can survive for certain periods of time, depending on their features. | desiccated |
| Physical methods of controlling the presence and growth of pathogens: Name five. | Heat, Cold, Dessication, Radiation, Filtration |
| Why do we use gas sterilizers? | To sterilize heat or moisture sensitive items. Will not damage delicate instruments, not corrosive, safe to use with microscopes and disposable plastic material. Permeate porous material. Dissipate rapidly. Cons: costly, toxic, explosive, carcinogenic |
| Pros and cons to Glutaraldehyde: | Pros: capable of effective sterilization @ room temperature (even endospores) Effective in the presence of organics. Cons: Not fast acting, severely irritate eyes, high concentrations burn skin, irritate nose, throat, coughing/wheezing, nausea, headaches |
| True or False: Newer Accelerated Hydrogen Peroxide products ARE effective disinfectants? (ex. Rescue) | True |
| Why is hydrogen peroxide an ineffective disinfectant and antiseptic? | Bacteria and body tissues contain enzymes (catalase) that inactivate hydrogen peroxide. (Release O)(left with water) Although, the release of oxygen can oxygenate deep wounds and kill strict-anaerobic contaminants. (ex. Clostridium tetani) |
| List some pros and cons to alcohol use as a disinfectant. ( Exert their action by denaturing proteins and dissolving lipids.) | Pros: Effectively kill bacteria and fungi. Fast acting, no residue (evaporate away), no staining. Cons: Not effective against endospores or non-enveloped viruses. Not very penetrating, no residual activity. |
| Name two alcohols used as disinfectants. | Aqueous Ethanol (60 - 95%), Isopropanol (common name: isopropyl alcohol) |
| Halogen used as a disinfectant @ 10% | Chlorine (Bleach) |
| Commonly used halogen for antiseptic use against microbes, fungi, and viruses. | Iodine |
| Two halogens regularly employed as antimicrobials. | Iodine, Chlorine Halogens are the seventh VII column of the periodic table of elements. |
| Attributes of Chlorhexidine: (one of the most popular antiseptic agents and a very popular surgical scrub. Must be diluted for most applications. | Effective antimicrobial agent (bacteria, mold, yeast, viruses) Rapid onset/long residual activity. Not affected by alcohol, lavage solutions, or organic material. Can be irritating to some humans and animals. Use caution around eyes. |
| Very small amounts of heavy metals (especially copper and silver) exert ______ activity. | antimicrobial |
| Cationic detergents that act by disrupting lipid bilayers and are bacteriocidal, fungicidal, viricidal (enveloped), and amoebicidal | Quats (Quaternary Ammonium Compounds) |
| _______ are artificial surfactants. | Detergents (ex. positively charged detergent: Quaternary ammonium compounds, aka quats. |
| Soaps are a natural product made up of: | sodium and potassium salts of fatty acids |
| True or False: Higher concentrations of disinfectant are preferable to lower concentrations. | False |
| ____ application times are preferable to ____. | Longer, shorter |
| Cold temperatures _____ disinfectant activities. | inhibit |
| True or False: Organic material (such as vomit and feces) frequently affects the actions of chemical control agents. | True, negatively affects. That is why it is important to cleanse before disinfecting. |
| ____ viruses are generally more resistant than ____ viruses to disinfectants and antiseptics. | non-enveloped, enveloped |
| ____bacteria, endospores, and protozoan _____, and oocysts are very resistant to disinfectants and antiseptics. | myco, cysts |
| Stationary-phase (non-growing) bacteria are generally ____ resistant than log-phase (growing) bacteria. | more |
| Gram ____ bacteria (with their outer membrane) are generally more resistant than gram _____ bacteria to disinfectants and antiseptics. | negative, positive |
| Fungus found in soil or bird feces that can affect the ocular, respiratory, CNS, and skin systems: particularly in cats and koalas | Cryptococcus |
| What techniques are employed in sterilization? | Moist heat or steam, radiation, chemicals (glutaraldehyde), and ethylene oxide (gas). Autoclaving is a common moist heat sterilization technique used in most hospitals and microbiology laboratories. |
| What are typically last to die when sterilizing equipment? | High heat and chemical resistant bacterial endospores |
| What do you call the total elimination of all microorganisms including spores (not possible on living tissue) | Sterilization |
| Four steps to cleansing | Rinsing - the object under cold water, Applying- detergent and scrubbing object, Rinsing- the object under warm water, Drying- the object prior to sterilization or disinfection. |
| What do you call the removal of soil or organic material from instruments and equipment & may be done, clinically, in four steps | Cleansing |
| What factors affect disinfectant performance? | Number of microbes, Nature of microbes in the population, Temperature + pH of environment, Concentration or dosage of agent, Mode of action of the agent, Presence of solvents, organic matter, inhibitors |
| List eight ideal disinfectant attributes | Resistant to inactivation, broadly active (killing pathogens), not poisonous (otherwise harmful), penetrating (pathogens), not damaging to non-living material, stable (won't degrade quickly), easy to work with, otherwise not unpleasant (sticky or smelly) |
| Any cleansing technique that mechanically removes microbes: | Sanitization |
| The process that destroys all visible microbes, including viruses and endospores. | Sterilization |
| Chemical formulated to be applied to living tissue? | Antiseptic |
| What do you call chemicals that can be applied to both animate (living) and inanimate objects for the purpose of eliminating pathogens? | Germicides |
| ____ are chemical solutions used to clean inanimate objects. (physical process (UV radiation may also be employed) | Disinfectants |
| The elimination of pathogens, except spores, from inanimate objects. | Disinfection |
| Veterinary examples of nosocomial infections: | Salmonella, Bite wounds, Pneumonia, Leptospirosis, Bovine Mastitis |
| Leptospirosis | Bacterial infection: affects people & animals. Passed through unhealed break in skin coming in contact with water/soil contaminated with urine. Fever, headache, bleeding, muscle pain, chills, red eyes, vomiting. Untreated: kidney and liver damage, death. |
| Distemper | Highly contagious viral disease of domestic dogs and ferrets, skunks, and raccoons. It is an incurable, often fatal, multi-systemic (affecting multiple organs) disease that affects the respiratory, GI, and CNS. |
| Nosocomial infections are: | Hospital acquired infections, usually bacterial. Environmental and antibiotic resistance. Organisms of potential concern: MRSA (Methicillin-resistant Staphylococcus), E. coli, Salmonella, Klebsiella, Enterobacter, Serratia, Pseudomonas |
| Nosocomial infections (sources) | Self-infection, cross-infection (hospital staff or patient -> patient) Environmental infection (water disinfectant, ventilators, endoscopes, dust, air, food, bowls, litter boxes, I.V. fluid cathetars |
| Three facts about zoonosis | Host of origin may have active disease. Host of origin may be asymptomatic. Disease may cycle in host species of origin and form reservoir for the other species. Bordetella in dogs. Bordetella in humans. |
| Disease transmission from animal -> human | zoonosis |
| Indirect transmission Passive ____ - flies, birds, rodents, veterinary staff _____ = reservoir host | vector |
| Direct Routes of Transmission One adult to another (secretion, sneezing/coughing, sexual transmission) | Direct Horizontal Transmission |
| Direct Routes of Transmission Through the placenta or egg, in utero. | Direct Vertical Transmission |
| Diseases transmitted from animal to animal of the same species may be spread: (2 ways) | Directly or Indirectly - reservoir, environment or vectors - animals infected with bacteria which do not have clinical signs yet shed the organism (may be part of normal flora or incubation period of disease) |
| Leptospira dry up _____, but survive for _____ weeks in water. | rapidly, 6 - 12 |
| Infectious agents can be transmitted from: (list two sources) | The environment (resevoir) or bacterial flora on skin getting into a wound. |
| What may provide bacteria with a means to colonize rapidly, seek specific tissues, and avoid the immune system? | Motility - flagella, cilia, spiral shape (spirochetes) |
| Enzymes Destroys tissue cement | Hyaluronidase |
| Enzymes Breaks down muscle collagen. Clostridium (i.e. cause of gangrene) | Collagenase |
| Enzymes Coagulation of fibrin protects bacteria from phagocytosis (i.e. Staph aureus) | Coagulase |
| Enzymes, usually proteins, destroy cellular structures and extracellular matrix. True or False | True |
| Endotoxin (Lipopolysaccharides) is released when the cell lyses causing: | Septic shock. All gram (-) bacteria cause similar signs. (fever, shock 1-2 hrs post exposure, severe diarrhea, change in immune status), Due to release of toxin, patients tend to get worse after treatment initially. (i.e. antibiotic treatment) |
| Toxic component of cell wall of gram (-) bacteria that is released when the cell lyses: Lipopolysaccharides (not proteins) | Endotoxin |
| Membrane damaging exotoxins include: | Protease & Phospholipase - Detergent-like action |
| Name the toxin and type that blocks inhibitory synaptic impulses resulting in rigid paralysis. | Tetanus - Exotoxin, stiffness, reluctance to move, twitching or tremors of muscles, lockjaw, prominent protruding third eyelid, unsteady gait with stiff tail. |
| Name the toxin and type that inhibits protein synthesis of host cells, causing cell death. | Diptheria - Exotoxin, diarrhea, vomiting, fever, clear nasal discharge, purulent eye discharge, lethargy, anorexia, cough |
| Name the toxin and type that inhibits acetylcholine release at the neuromuscular junction and causes flaccid paralysis. | Botulism - Exotoxin, muscular weakness, constipation, stumbling, knuckling |
| Proteins excreted by bacteria that are destroyed by heat are called: | Exotoxins |
| Hair-like extensions on bacteria that enable the organism to attach to tissue (may be tissue specific) | Pili |
| Polysaccaride coat that protects against phagocytosis and increases the ability to take in nutrients? | Glycocalyx (capsule or slime coat) "sugar coat" |
| Name five virulence factors. | Capsules (slime coat), Mobility (flagella, cilia), Adhesion (Pili), Enzyme production, Toxin production (endotoxin or exotoxin) |
| Properties of a microorganism that cause disease in host or increase ability to colonize host? | Virulence factors |
| The ability of an organism to cause disease (virulence factors, number of initial organisms, immune status of host) | Pathogenicity |
| Host Defenses: Specific | Humoral Immunity: Antibody mediated (extracellular antigens) (B-cells: produce and secrete antibodies, activating immune system. Cell Mediated Immunity (Immune cells (intracellular antigens) T-cells: only recognize viral antigens outside the infected cell |
| Host Defenses: Nonspecific | flushing mechanisms, skin & mucus membrane, chemical barriers, biologic barriers |
| Symbiosis "living together" The relationship hurts the host | Pathogen |
| Symbiosis "living together" Relationship benefits one, but has no effect on the other. | Commensal |
| Symbiosis "living together" Relationship benefits both organism and host | Mutual |
| Proving that a specific organism is causitive to a specific disease. isolated (diseased, but not healthy animals) growth (pure culture) induced disease (susceptible animal) re-isolated (susceptible animal) | Koch's Postulates |
| A lower MIC is an indication of a ____ antimicrobial agent. | better - A lower concentration of antibiotic in the broth is effective |
| An MIC based on serial dilutions is generally considered the most basic and _____ laboratory measurement of the activity of an antimicrobial agent vs an organism | accurate |
| What is an MIC? | The minimum inhibitory concentration of an antimicrobial that will inhibit the visible growth of a microorganism after overnight incubation |
| Antibiotic that prevents bacteria from multiplying (but immune system must kill bacteria) | bacteriostatic |
| Antibiotic that kills bacteria? | bacteriocidal |
| The effectiveness of individual antibiotics varies with: | location of the infection, the ability of the antibiotic to reach the site of infection, the ability of the bacteria to resist or inactivate the antibiotic |
| The area nearest the antibacterial disc has the ____ concentration of antibiotic. | highest |
| Why do we bother to test antibiotic sensitivity? | Helps us choose which antibiotic to treat the animal. Research: What bacteria are resistant. Why? Is the susceptibility changing over time? |
| What is the are of no growth around a disc called? | Zone of Inhibition |
| What does "Resistant" mean? | Bacteria are able to grow despite the presence of an antibiotic. |
| What are two forms of antibiotic testing? | Kirby Bauer Agar Diffusion Method: Meuller-Hinton agar. Not differential or selective. MIC: Minimum Inhibitory Concentration (test tubes) |
| A coagulase test will differentiate between? | Staphylococcus aureus (positive-cottage cheese), and Staphylococcus epidermis, S. haemolyticus, S. saprophyticus (negative-no gloop or cheesy clump) |
| Why do we perform a catalase test? | To detect the presence of catalase (an enzyme that degrades hydrogen peroxide) fizzing - positive result - release of O2. Staphylococci (positive) Streptococci (negative) |
| To prevent overgrowth of contaminating organisms of commensals transport media should be: | Sent to the laboratory immediately and stored at room temperature |
| Media designed to keep microbes alive, but does not encourage growth or reproduction (ex. culturette for anaerobic or aerobic bacteria) | Transport Media |
| Culture Media Identify specific species (color change) | Differential Media |
| Culture Media Encourages growth of specific bacterial group. | Selective Media (agar) |
| Culture Media General support for many bacterial types | Nutrient agar (broth or transport) |
| What is the general pH range that bacteria thrive at? | 6.5 (acidic, pH <7) - 7.5 (slightly basic, pH > 7) |
| At what temperature and for how long do you incubate inoculated plates? | 37 degrees C (98.6 degrees F) for 24-48 hrs |
| Culture medium designed to grow gram negative bacteria and differentiate them for lactose fermentation? | MacConkey Agar - Contains bile salts and crystal violet to inhibit gram positive bacterial growth |
| What do you call media that is designed in such a way that different bacteria can be recognized on the basis of their colony color? | Differential Media - Example: MacConkey agar bile salts and crystal violet |
| Complete hemolysis - clear (read print through it) | Beta hemolysis |
| Partial hemolysis - green hue | Alpha hemolysis |
| No hemolysis - no change in agar | Gamma hemolysis |
| Growth on blood agar differentiates between? | Hemolytic bacteria and Non-hemolytic bacteria |
| Blood agar is regular agar which has what added to it? | Sheep RBC |
| What do you call lysis of a RBC by enzymes produced by some bacteria? | Hemolysis |
| What type of media is blood agar? | Differential Medium (color change) Enriched Media |
| Why do we need selective and/or differential media? | Allows bacteria to be differentiated into groups by biochemical reactions. Grows "fussy" fastidious bacteria that does not grow well on other media. Selective media contain antimicrobial substances, such as bile salts, which inhibit or kill all but a few |
| True or False: Gram positive bacteria have a thicker peptidoglycan layer which allows them to retain more crystal violet stain? | True |
| Thick layer in the cell of gram positive bacteria is called? | Peptidoglycan |
| What is a pleomorphic bacterial shape? | Multiple shapes ranging from cocci to bacilli |
| What is a mordant? | It binds a chemical dye and holds it down, such that the dye sticks to the organism |
| Gram stain kits include: | Crystal violet (stains gram positive bacteria), Iodine (mordant), Alcohol (decolorizer), Basic Fuchsin or Safranin (stains gram negative bacteria) |
| Slides made from bacteria and stained with GRAM STAIN are frequently used to categorize bacteria as: | Gram positive (stain purple/blue) or Gram negative (red/pink) |
| Under the microscope bacteria are characterized by? | Size & Shape - Bacilli (rods), Cocci (spheres), Spirochetes (spirals) |
| What is the primary purpose of microbiology exams? | bacteriology |
| Bacterial Identification What are some important microscopic characteristics? | -shape -size -arrangement -staining characteristics (Gram stain - positive or negative), -other stains |
| Bacterial Identification What are some bacterial interactions with media? | Hemolysis, Color change, Swarming (Motility) |
| Bacterial Identification Colony characteristics of specific media? | -Color -Shape |
| Why do we streak agar plates with the quadrant method? | To isolate bacterial colonies. |
| What three factors do we need to keep in mind when culturing bacteria? | Nutrient, Temperature, and Oxygen requirements |
| Where does identification of infectious agents happen? | General hospital laboratory - Physiological tests Reference laboratories - Genetic tests |
| Why do we identify infectious agents? | Aids in treatment. Helps antibiotic selection and aids in determining treatment duration. Prevention of future disease. |
| What happens when normal flora gets into areas that should not have bacteria? | The bacteria become pathogenic. Significant disease can be produced. |
| What parts of the body do not have bacteria? | Spinal fluid, brain, urinary bladder, lower respiratory tract, joints, synovial fluid, bone marrow |
| What parts of the body have bacteria normally? | Small intestine, skin, nasal passages, colon, mouth |
| Enzyme-Linked Immunosorbent Assay also known as? | ELISA |
| Why do we heat fix samples? | Prevents sample from washing off, helps preserve cell morphology, kills bacteria, renders permeable to stain |
| Community of microorganisms adhered on a surface “Cities of microbes” Resistant to antibiotics. Example: plaque on teeth | Biofilm |
| Exotoxins: Destroyed by heat. Proteins excreted by bacteria, examples: | Botulism toxin: inhibits acetylcholine release at the neuromuscular junction, causing paralysis. Tetanus toxin: blocks inhibitory synaptic impulses resulting in rigid paralysis. Diptheria toxin: inhibits protein synthesis of host cells, causing cell death |
| Endotoxins: Toxic components of cell wall of gram (-) bacteria. Lipopolysaccharides (not proteins!) | Released after cell lyses. Septic Shock. If antibiotics given, bacteria killed and toxins released. Patient may initially get worse! All gram (-) bacteria cause similar signs: Fever, Shock (1-2 hours post exposure), Severe diarrhea, Change immune status. |
| Spiral-shaped motile bacteria. Zoonotic potential! (urine exposure) May be asymptomatic in reservoir animals. Rodents, raccoons, livestock spp. Cats are naturally resistant. Humans, dogs, livestock may die of liver or kidney failure. | Leptospirosis |
| Affects dogs & humans (not cats). Rare in WA has been reported) Transmission: deer ticks-Ixodes spp. Attached for at lease 24 hrs. Symptoms: Skin rash @ tick bite. Fever, muscle aches, enlarged lymph nodes, Neurologic, Kidney, Heart disease, arthritis | Lyme Disease (Borrelia burgdoferi) |
| Anthrax, Brucellosis, Glanders, Disease of suspected bioterrorism origin, E. coli – "Shiga toxin-producing E. coli", Influenza virus, novel strain, Leptospirosis, Plague, Psittacosis, Q Fever, Rabies, Tularemia | Reportable diseases in WA |
| Damage cell membrane. Extinguish host cells normal mechanisms for survival (DNA, RNA, protein synthesis). Attract lymphocytes to kill invaded cell. Transform cell into cancer. Host killed due to dependence on invaded cells. | How do viruses cause death of cells? |
| Physical Agents: Steam heat for 15 minutes boiling. Dry heat for 30 minutes. Radiation: UV light. Ionizing. Chemical Agents: Alcohols, Sterilizing gases (ethylene oxide). Halogens, Phenolics, Detergents: Cidex. Oxidizing agents: Accelerated H2O2 | How do you kill a Virus? |
| Who? all mammals susceptible. What? neurologic disease, always fatal. Where? most of world, except islands. How? direct contact with saliva or tissue. Dx: brain immunofluorescence, tissue ELISA. Tx: none Vaccinate to prevent !! Quarantine suspects!! | Rabies |
| Who? wild & domestic dogs. What? potentially fatal vomiting/ bloody diarrhea/ low white count. Where? worldwide. How? fecal-oral transmission. Dx: fecal ELISA. TX: supportive care, vaccinate to prevent. No envelope. Difficult to kill virus! Use Bleach! | Canine Parvovirus |
| Who? domestic and wild cats. What? cancer or bone marrow disorder. Where? worldwide. How? retrovirus main transmission by saliva, also urine & feces. Prevention by testing and vaccination. | Feline Leukemia Virus |
| fever, oral ulcers, breathing effort, limping | Calici virus |
| FVR or FHV-1 or feline herpes sneezing, fever, nasal & ocular discharge, possible corneal ulcers. 80% become chronic carriers. | Rhinotracheitis |
| 1-5% mortality rate. Currently diagnosed in 46 states Highly contagious (cats too!) No human cases associated with it. | Canine Influenza |
| What? neurologic disease caused by prion that causes “sponge” appearance to brain. Who? sheep, cattle, humans, all mammals How? ingestion of contaminated food (carcass). Where? Great Britain, Europe, Canada & USA. Called Creutzfeldt-Jakob Disease- humans | Mad Cow Disease |
| Damage cell membrane Extinguish normal cell function Attract killer lymphocytes Transforming cells into cancer Host death by interfering with homeostasis (DEATH) | Viruses kill cells via |
Created by:
Raevyn1
Popular Veterinary sets