Term
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Definition
When both the host and organism benefit from the relationship i.e. bacteria in human colon |
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Term
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Definition
When the organism benefits from the relationship and the host is harmed i.e. tuberculosis bacteria in the human lung |
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Term
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Definition
When the host is not affected by the relationship and the organism is benefited i.e. Staphyloccus on skin |
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Term
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Definition
Ability of a pathogen to cause disease in an organism |
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Term
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Definition
Describes the particular attributes of a specific microbe (species or strain) that promote pathogenicity; virulence can be a quantifiable term (avirulent, mildly virulent, and highly virulent). Virulence depends on virulence factors |
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Term
Describe the term “normal microbiota” |
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Definition
Normal microbiota refers to the organism that colonizes the body’s surfaces without normally causing disease. In-utero, the fetus is free of normal flora in normal circumstances; the process of being colonized (establishment of microbial growth) with normal flora typically begins during the birthing process: MO of the GI tract MO of the skin MO of the genitourinary tract. Other forms of normal flora are acquired throughout the early years of life via environmental exposure: Food that we eat Person-to-person contact Environmental/airborne organisms |
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Term
Describe the terms resident and transient microbiota |
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Definition
Resident microbiota permanently colonizes the host and is established during the first months of life. Transient microbiota colonizes the host for a short period of time and do not persist in the body due to the host’s defenses. |
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Term
List the areas on/in the human body that have normal microbiota and those areas that are axenic (considered to be sterile). |
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Definition
Normal microbiota Eyes and skin Upper respiratory tract Upper digestive tract Lower digestive tract Female/male urinary and reproductive systems Axenic (sterile) Body fluids (CSF), organs and blood |
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Term
Describe probiotics and the benefits of having normal flora |
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Definition
Probiotics are live microbes applied to or ingested into the body that intend to exert a beneficial effect. Normal flora provide dietary nutrients (e.g. vitamin k, B-12) Bacterial antagonism: (normal vs. normal and normal vs. transient): -Nutrient competition |
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Term
Describe three conditions that create opportunities for normal microbiota to become an opportunistic pathogen. |
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Definition
1. Immune suppression 2. Changes in the normal microbiota (changes in relative abundance of normal microbiota may allow opportunity for a member to thrive and cause disease) 3. Introduction of normal microbiota into sterile area of body (axenic environment) |
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Term
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Definition
Presence of microbes in or on the body |
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Term
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Definition
Results when the organism has evaded the body’s external defenses, multiplied and become established in the body |
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Term
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Definition
Results only if the invading pathogen alters the normal functions of the body; disease is also referred to as morbidity |
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Term
Describe the four portals of entry through which pathogens invade the body. |
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Definition
Skin- Via openings or cuts, burrowing into or digesting the outer layers of skin Mucous membranes- Exposure to environment Parenteral route- Requires direct deposit onto tissues by punctures, cuts, bites, stab wounds, deep abrasions or surgery Placenta- From mother to fetus |
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Term
Discuss how the virulence factors help microbes establish disease in humans. |
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Definition
Adhesion factors- Structures or proteins used for attachment of pathogen to host cell Biofilms- Community of glycocalyx attached to a surface within the host, they are extremely resistant to host defenses Extracellular enzymes- Enzymes secreted by the pathogen, dissolve structural chemical in the body and help the pathogen maintain infection, invade further and avoid body defenses Toxins- Chemicals that harm tissues or trigger host immune responses that cause damage. Antiphagocytic factors- Certain factors prevent phagocytosis by the host’s phagocytic cells Bacterial capsule is often composed of chemicals found in the body and not recognized as forgein Antiphagocytic chemicals some prevent fusion of lysosome and phagocytic vesicles and leukocidins directly destroy phagocytic white blood cells |
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Term
Differentiate between bacterial exotoxins and endotoxins. |
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Definition
Exotoxins destroy host cells or interfere with host metabolism Endotoxins are released when bacteria dies (Lipid A) |
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Term
Differentiate between a sign, symptom and syndrome |
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Definition
SIGN- Objective manifestations of disease that can be observed or measured by others SYMPTOM- Subjective characteristics of disease felt only by the patient SYNDROME- Group of symptoms and signs that characterize a disease or abnormal condition |
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Term
Describe the five stages of infectious diseases. |
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Definition
Incubation period- No signs or symptoms Prodromal period- Vague general symptoms Illness- Most severe signs and symptoms Decline- Declining signs and symptoms Convalescence- No signs of symptoms |
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Term
Describe the reservoirs of infection and give an example of a disease that humans acquire from that reservoir. |
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Definition
Reservoirs of infection- Continual source of infection where pathogens can persist and maintain their ability to infect. AIDS, gonorrhea, typhoid fever are asymptomatic infections or latent diseases that are reservoir infections. |
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Term
Explain how microbes are transmitted from one host to another via contact transmission. |
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Definition
Contact transmission Direct contact e.g. handshaking, kissing, sexual intercourse, insect bites Indirect contact e.g. drinking glasses, toothbrushes, toys, punctures Droplet transmission e.g. droplets from sneezing (within 1 meter) |
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Term
Explain how microbes are transmitted from one host to another via vehicle transmission. |
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Definition
Vehicle transmission Airborne e.g. dust particles Waterborne e.g. streams and swimming pools Foodborn poultry, sea food, meat |
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Term
Explain how microbes are transmitted from one host to another via vector transmission. |
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Definition
Vector transmission Mechanical e.g. insect bodies (fleas, roaches) Biological e.g. lice, mites, mosquitoes and ticks |
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Term
Distinguish between the following terms used to classify infectious diseases. Acute vs chronic |
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Definition
Acute- Disease in which symptoms develop rapidly and that run its course quickly Chronic- Disease with usually mild symptoms that develop slowly and last a long time |
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Term
Distinguish between the following terms used to classify infectious diseases Communicable vs contagious vs noncommunicable |
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Definition
Communicable disease- Disease transmitted from one host to another Contagious disease- Communicable disease that is easily spread Noncommunicable disease- Disease arising from outside of hosts or from opportunistic pathogen |
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Term
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Definition
The study of where and when disease occurs and how they are transmitted in a population |
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Term
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Definition
Incidence- Number of new cases of a disease in a given area during a period of time Prevalence- Number of total cases of a disease in a given period of time |
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Term
Endemic vs epidemic vs pandemic |
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Definition
Endemic- Disease that is constantly present in a population in a geographic location but numbers/severity is too low to pose threat Epidemic- Disease acquired by many hosts in a given area in a short time (higher than normal incidence) Pandemic- Worldwide epidemic |
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Term
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Definition
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Term
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Definition
Morbidity- Incidence of a specific notable disease, number of people affected/total population in a given time period Mortality- Deaths from notable disease, number of disease/total population in a given time |
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Term
Define three types (sources) of nosocomial infections and explain how health care workers can decrease the risk of these infections in patients. |
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Definition
Exogenous- Pathogen acquired from the health care environment Endogenous- Pathogens arise from normal microbiota due to factors within the health care setting Latrogenic- Results from modern medical procedures |
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Term
17. Describe three factors that influence the development of nosocomial infections. |
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Definition
Presence of microorganisms in the hospital environment Immunocompromised patients Transmission of pathogens between staff and patient and among patients |
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Term
1. Explain the difference between fungi and bacteria in regard to cell type, cell wall composition, spore production and sensitivity to antibiotics. |
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Definition
Fungi
Cell type: Eukaryotic
Cell wall composition: Sterols present
Spore production: Produce a wide variety of sexual and coexual reproductive spores
Sensitivity to antibiotics: Often sensitive to polyenes, imdazoles and griseofulvin
Bacteria
Cell type: Prokaryotic
Cell wall composition: Peptidoglycan
Spore production: Endospores (not for reproduction) and some asexual reproductive spores
Sensitivity to antibiotics: Often sensitive to penicillins, tetracyclines and aminoglycosides |
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Term
Discuss the optimal growth temperature, cellular and colonial morphology of yeast and molds |
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Definition
Yeast
Optimal growth temperature 37 C
Cellular morphology Unicellular
Colonial morphology Oval, white colonies
Mold
Optimal growth temperature 25 C
Cellular morphology Multicellular
Colonial morphology Both vegetative and aerial hyphae |
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Term
Differentiate between aerial and vegetative hyphae. |
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Definition
Aerial hyphae Hyphae that is above the nutrient surface Vegetative hyphae Hyphae that is below the nutrient surface |
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Term
Define “dimorphism” and list the five dimorphic fungi that cause disease in humans |
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Definition
Dimorphic: Are yeast at 37 C (in the body) and mold at 25 C (in nature)
Sporothrix schenkii causes rose thorn disease or gardener’s disease Coccidioidomycosis San Joaquin valley fever Histoplasmosis Ohio valley fever Blastomycosis Chicago disease or North American Blastomycosis Paracoccidiodomycosis South American Blastomycosis |
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Term
Classify fungus by their sexual means of sporulation (produce aerial hyphae). |
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Definition
Zygomycete: produce zygospores i.e. Rhizopus (bread mold) Ascomycete: produce ascospores i.e. penicillium, saccharomyces Basidiomycte: produce basidiospores i.e. mushrooms, crytococcus Deuteromycete: reclassified using DNA technology i.e. stachybotrys, pneumocystis |
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Term
Recognize the asexual spores produced by fungus (used to classify in clinical lab). |
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Definition
Sporangiospores: form in sac called sporangium Conidiospores: no sac, form at tip or side of hyphae Chlamydospore: thickened cell wall inside hyphae |
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Term
Name the classification of fungal diseases based on the location in the body. |
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Definition
Systemic mycoses: Deep within the body Subcutaneous mycoses: Beneath the skin Cutaneous mycoses: Affect hair, skin and nails Skuperficial mycoses: Localized on the outermost skin layers/hair shafts Opportunistic mycoses: Caused by normal microbiota or fungi that is normally nonpathogenic |
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Term
Discuss the causative agent (name of the fungus that causes the disease), geographic location, and route of transmission of the following diseases
Coccidioidomycosis (San Joaquin Valley fever) |
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Definition
Name of fungus: Coccidioidomycosis immitis
Geographic location: Thrives in areas with sandy alkaline soils, very high temperatures, Low rainfall, and low elevation
Route of transmission Airborne arthrospore is inhaled |
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Term
Discuss the causative agent (name of the fungus that causes the disease), geographic location, and route of transmission of the following diseases:
Histoplasmosis (Ohio Valley fever) |
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Definition
Name of fungus: Histoplasmosis capsulatum
Geographic location: Mostly in eastern United States but also in Africa and Asia
Route of transmission: Inhalation of spores into the lungs |
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Term
Discuss the causative agent (name of the fungus that causes the disease), geographic location, and route of transmission of the following diseases:
Blastomycosis (Chicago disease, North American Blastomycosis) |
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Definition
Name of fungus: Blastomycosis dermatitidis
Geographic location: Southeastern United States north to Canada
Route of transmission Inhalation of dust can carry fungal spores or hyphal pieces into the lungs |
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Term
Discuss the causative agent (name of the fungus that causes the disease), geographic location, and route of transmission of the following diseases:
Paracoccidioidomycosis (South American Blastomycosis) |
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Definition
Name of fungus: Paracoccidioidomycosis brasiliensis
Geographic location: Southern Mexico and South America
Route of transmission Inhalation of sprores |
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Term
Recognize the three fungi that are dermatophytes |
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Definition
Trichophyton Epidermophyton Microsporum |
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Term
Discuss the causative agent and characteristics of the following fungal infections:
Cryptococcal meningitis |
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Definition
Most common clinical form of cryptococcal infections Follows dissemination of the fungus to the CNS
Symptoms include headache, stiff neck, nausea, photophobia, hallucinations, and fever |
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Term
Discuss the causative agent and characteristics of the following fungal infections:
Rose thorn (Gardener's) disease- Sporotrichosis |
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Definition
A subcutaneous infection that is usually limited to the arms and legs
Individuals who work with natural plant material are at highest risk for infection
Symptoms include nodular lesions around the infection site and secondary lesions can occur on the skin along the course of lymphatic vessels |
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Term
Discuss the causative agent and characteristics of the following fungal infections
Ringworm (Dermatophytosis) |
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Definition
Fungal infections of the skin, hair, nails
Result from fungi that use keratin as a nutrient source and thus colonize only dead tissues
Symptoms include a skin lesions that resembles a worm lying below the surface of the skin
Can provoke cell mediated immune response that damages living tissues |
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Term
Discuss the causative agent and characteristics of the following fungal infections:
Candidiasis (Thrush, Vaginitis, Diaper rash, Onychomycosis) |
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Definition
Most common causative agent
Normal flora of skin and mucous membrane
can be transmitted between individuals
always an opportunist infection that produces a wide rage of diseases |
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Term
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Definition
Mushroom poising from eating a fungus |
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Term
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Definition
A chronic, slowly progressing fungal infection usually of the foot or leg, characterized by nodules that discharge oily pus |
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Term
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Definition
Caused by eating foods contaminated with fungal toxins |
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Term
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Definition
Normal byproducts of metabolic activities but are poisonous to animals and humans |
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Term
Name two mycotoxins produced by fungus |
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Definition
Aflatoxins: Produced by Aspergillus flavus
Ergot alkaloids: Used to make drugs that treat migraine headaches, constrict blood vessels and stimulates labor contractions |
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Term
Differentiate between bacteria and virus particles |
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Definition
Viruses are much smaller than bacteria
Viruses contain DNA or RNA bacteria contain DNA
Viruses are acellular particles and bacteria are living organisms
Viruses are not susceptible to antibiotics bacteria are susceptible to antibiotics |
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Term
Describe the parts of a viral particle and their purpose: |
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Definition
Genome Either RNA or DNA (never both) either single or double stranded usually circular but may be linear
Capsid Protein coat composed of repeating protein subunits (capsomeres) provide protection and attachment sites
the viral caspid determines the viral shape (helical, lcoshaderial, or compelx)
Envelope Acquired from host cell during viral replication or release envelope is a portion of membrane system of host composed of phospholipid bilayer some proteins are virally-coded glycoproteins (spikes) envelopes proteins and glycoproteins often play a role in host recognition
Virion A viruses extracellular state, a viral particle that is infectious and ready to attack |
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Term
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Definition
The type of host that it can infect, most viruses can only infect particular kinds of host cells, due to affinity of viral surface proteins/glycoproteins for complementary proteins/glycoproteins on host cell |
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Term
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Definition
The cell type or tissue within a host cell that it can infect (HIV infects T helper WBC, Rabies infects nervous tissue) |
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Term
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Definition
The time from when a virus enters cells to when it is released |
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Term
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Definition
Number of viruses produced and released, depends on the type of virus and size and initial health of host cell |
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Term
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Definition
When animal viruses remain dormant in host cells, may be prolonged for years with no viral activity, signs or symptoms. |
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Term
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Definition
When a latent virus is incorporated into host DNA and becomes a permanent part of the hosts chromosome |
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Term
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Definition
A virus that has a capsid and a nucleic acids (no envelope) |
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Term
Differentiate between bacteriophage lytic and lysogenic cycles. |
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Definition
Lytic cycle Replication cycle usually results in death and lysis of host cell
Lysogenic cycle Replication cycle may include viral nucleic acid incorporated into host DNA (prophage) |
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Term
Describe the six steps of animal virus replication |
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Definition
Attachment Chemical attraction, animal viruses don’t have tails or tail fibers they have glycoprotein spikes or other attachment molecules that attach to cell membrane
Entry Whole viral particle enters the cell
Uncoating Caspid is degraded
Synthesis Production of nucleic acids and proteins
Assembly Nucleic acids and caspid proteins assemble
Release By budding or rupture |
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Term
Plaque formation (phage typing) |
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Definition
The culturing of bacteriophage in bacteria, the virus infects the bacteria, the bacteria are lysed, die and show up as clear areas on the media |
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Term
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Definition
When a cell looks sick, when you can visually see the infected cell in the lab |
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Term
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Definition
Visible evidence that cells are infected with a virus, produce an inclusion within the infected cell |
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Term
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Definition
Monolayer of cells with nutrients for cells, the cells are the bacteria (media) that the virus infect |
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Term
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Definition
Use antibodies to identify viruses, it detects patient antibodies against viruses |
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Term
Describe how interferon and antiviral drugs are able to inhibit viral replication |
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Definition
Antiviral drugs Prevent attachment Nucleotide base analogs (look like A,T,C,G U but don’t act the same way) Reverse trancriptase inhibitors Protease inhibitors Neuraminidase inhibitors (H1N1 virus)
Interferon Proteins produced by an infected cell that signals a non-infected cells to begin producing antiviral proteins |
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Term
Differentiate between inactivated, attenuated and subunit vaccines |
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Definition
Inactivated “Killed” virus by heat or chemical
Attenuated “Weakened” virus
Subunit Protein molecules produced by genetic engineering |
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Term
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Definition
Tiny fragments of RNA without a capsid; cause disease in plants |
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Term
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Definition
Proteins without nucleic acids, inherited and transmissible by ingestion, transplant, and surgical instruments |
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Term
Describe how prions “replicate”. |
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Definition
Prions "replicate" by changing the structure of the already existing cellular PrP (normal) into the (abnormal)prion PrP |
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Term
Name the disease caused by prions. |
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Definition
Spongiform encephalopathies |
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Term
State the method needed to inactivate a prion. |
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Definition
Only destroyed by incineration or autoclaving in 1NaOH |
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