Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Principles > Microbiology > Flashcards

Microbiology Flashcards

1
Q

How is the prokaryote chromosome like?

A

Single, super-coiled, double stranded closed circular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which eukaryote has cell wall? What is it known as?

A

Fungi

Sterols

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do prokaryotes divide?

Which organism is particularly slow to grow?

A

Binary fission.

TB.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q 
What is the role of gyrases?
Which antibiotic class target this?
A

Relieves unwinding stress.

Quinolones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Does nucleoid have a nuclear membrane?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What 2 compounds are found in the peptidoglycan as repeated polysaccharide structure?

A

NAM and NAG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which antibiotic class target the cell wall?

Are they bacteriostatic or bactericidal?

A

B-lactams (Penicillin, Cephalosporins) and Glycopeptide

Bactericidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the cell wall like in gram-positive organisms?

A

THICK MULTI-layered peptidoglycan with glycolipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the cell wall like in gram-negative organisms?

A

LPS at the outermost surface followed by outer membrane then thin peptidoglycan layer followed by inner membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which layer of cell wall is responsible for endotoxin?

This is found in gram-___?

A

LPS - antigenicity, pro-inflammatory.

Gram Negative.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What charge does LPS give the cell membrane?

A

Negative due to phosphate groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 3 arrangements of proteinaceous extensions?

A

Monotrichous, Lophotrichous, Peritrichous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Rotary movement of flagella is?

Is the flagella antigenic?

A

H+ dependent.

Yes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the fimbriae/ pilli involved in? (3)

A

Surface attachment/ biofilm formation
Horizontal DNA transfer
Mobility (not for gram-neg)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the sequence to identify the 16s rRNA in mRNA?

A

Shine Dalgarno sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Is the prokaryotic mRNA polyadenylated?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Since there is no golgi apparatus in prokaryotes, which organelle processes proteins?

A

Cytoplasmic membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How do transcription and translation occur in prokaryotes?

A

Simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What kind of prokaryotes grow best at 37 deg?

A

Mesophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What pH range and osmolarity is ideal for human commensals?

A

pH6.8-7.2.

0.85% NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Does heterotrophs or autotrophs require carbon source to be provided?

A

Heterotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What respiratory method does facultative anaerobes use?

A

Preferentially uses O2 as terminal electron acceptor but able to switch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What respiratory method does aerotolerant anaerobes use?

A

Anaerobic metabolism.

Just able to tolerate O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the difference between obligate anaerobes and capnophillic organisms in the presence of O2?

A

Obligate anaerobes are killed in O2

Capnophiles not necessarily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Are obligate anaerobes or aerobes able to generate more ATP?
Obligate aerobes as O2 has higher reductive potential than nitrates/ sulfates
26
What are the 4 phases of growth in prokaryotes?
Lag Exponential/Log Stationary/ Plateau Death/Decline
27
What are chains, clusters, rod, curved rod morphologies called?
Chains - cocci Clusters - coccus Rod - bacillus Curved rod - Vibrio
28
What is the difference between a Spirillum and Spirochaete?
Spirillum - rigid spiral bacterium | Spirochaete - flexible spiral bacterium
29
How does spiral bacteria move? | What kind of solution can they move better in?
Cock-screw movement. | Viscous solution such as saliva and semen
30
How does fusiform bacteria look like?
Elongated and slender with tapered ends
31
What is the 2nd most common cause of sore throat?
Fusiform
32
What characteristics does a capsule provide a bacteria with? (3) 1 example of a bacterium with capsule
Phagocytosis protection, Virulent, Part of biofilm Klebsiella pneumoniae.
33
What are spores? When do they form? What is term for when a spore becomes active again? 1 example of a bacterium that produces spore.
Inert structures resistant to physical and chemical challenge. Forms when cells cannot grow due to stressors. Germination. C. Difficile
34
It is the retention of which solution (2) in what structure that gives gram positive its colour? What colour is it?
Crystal violet, Iodine (mordant) In thick peptidoglycan. Purple.
35
What colour do gram-negatives stain? What is it stained by? (2)
Pink. | Safranin Pink or Basic Fuchsin (Counter-stain)
36
What is used as the decolouriser in gram-staining?
Ethanol
37
``` Which organisms (2) shows gram-variability? Due to?? What stain should be used then? ```
M. tuberculosis due to waxy, lipid-rich cell wall thus stain not taken up well. Use Acid-fast (Ziehl Neelson) stain Spirochaete as it is too thin to take up crystal violet. Use silver impregnation.
38
What component in the mannitol salt agar preferentially selects for what kind of bacteria?
7.5% salt. | For Staphylococci.
39
Salmonella-Shigella agar contains what to inhibit what organisms?
Contains bile salts to inhibit coliforms
40
What is the difference between a selective and differential media?
Selective - select/ permit growth of 1 organism over another | Differential - producing visible changes in colonies for identification
41
What does MacConkey agar help to identify? What is the colour? What are the 2 inhibitors in it and what does it inhibit?
Enterobacteriaceae - turns neutral red to pink from fermenting lactose. Contains bile salts and crystal violet to inhibit gram negative enteric bacilli.
42
What does eosin-methylene blue media inhibits? | What does it differentiate and how?
Inhibits gram positives. Lactose fermenters: Produce acid and absorbs dye -> Purple black (Or metallic green sheen for E.Coli) Non-lactose fermenters: Protein deamination -> increase pH -> dye not absorbed -> colourless
43
What colour does E.Coli produce in the eosin-methylene blue media?
Metallic green sheen
44
What bacteria is blood agar specifically used to identify? On the basis of what?
Streptococcus spp. | Via haemolysis
45
What are the 3 types of haemolysis on a blood agar and what are their colours?
a (incomplete) - greenish discolouration around colonies (Hb oxidation to MetHb by H2O2) B (complete) - Yellow and complete clearing around colonies due to streptolysin y - no change, no haemolysis
46
Which lancefield groupings show B-haemolysis and which show y-haemolysis?
B: A (S. pyogenes), B, C (Large pyogenic or small colonies), F, G y: D
47
What organism produces endotoxin and what produces exotoxins?
Endotoxin - Gram neg (from LPS) | Exotoxin - Gram Pos
48
Which bacteria is coagulase positive?
S. Aureus
49
Which bacteria hydrolyses lipid?
Clostridia spp.
50
What is the difference between polyclonal and monoclonal Ab?
Polyclonal - to a specific microbe/ virus | Monoclonal - to specific component
51
Slide agglutination reactions show that what is present? | What kind of tests are these?
Antigens (sample) to a particular anti-sera (from lab). Serological tests.
52
What are the 4 stages of PCR?
Denaturation of DNA Annealing of primers to target Extension via polymerase Amplification
53
What kind of rRNA is high conserved (evolves slowly) and varies between strain? Thus can be ribotyped
16S rRNA
54
What is needed to interpret the mass spectrum result produced from a MALDI-TOF?
A reference library to compare
55
What is microbiome?
Study of genetic material of all microbes living on/ inside the human body
56
What does virulence mean?
Capacity of microbe to cause host damage
57
What are the terms used to describe an endogenous organism with a mutualistic relationship with the host that limits threat from exogenous pathogens?
Commensals/ Symbiotic relationship
58
What are organisms that cause infection when there is a change in natural immunity (E.g. Immunocompromised)? Are these usually endo or exogenous?
Opportunistic pathogens. Endogenous.
59
What are organisms growing in culture by accident known as?
Contaminant
60
``` What organism (and what kind) causes thrush in the throat/ GU tract or skin? When does this occur? ```
Candida, a fungi. | Immunocompromised state.
61
How do yeast (fungi) multiply?
Budding
62
What does the tip of true hyphae contain?
Proteases to break surfaces
63
What is a common mould (fungi) that infects the immunocompromised?
Aspergillus spp.
64
What are organisms causing Malaria, E. histolytica and cryptosporidiosis called?
Protozoa
65
How does Neisseria meningitidis and neisseria gonorrhoeae appear in microscopy?
Gram-negative diplococci growing intracellularly
66
A pink diplococci bacteria that grows intracellularly is seen on microscopy. What are the 2 possible bacteria?
Neisseria meningitidis | Neisseria gonorrhoeae
67
What are 4 gut commensals (Coliforms)?
Most E.Coli Klebsiella Enterobacter Proteus
68
Salmonella, Shigella and E.Coli O157 (Coliforms) causes pathology where?
GI
69
Coliforms are gram?? Morphology?
Gram negative bacilli
70
What are Gram negative bacilli from the normal bowel flora called?
Coliforms
71
What is the 1st line abx used to treat coliforms? | Route of administration and 1 potential side effect?
Gentamin. | IV, Nephrotoxic.
72
What is the exotoxin superantigen produced by S. Auerus?
TSST-1
73
What could adversely happen when a coliform dies?
Endotoxin will be released from the cell wall (LPS) causing inflammation and sepsis
74
What are the 3 components of the LPS? (From inner to outer)
Lipid A, Core, O Antigen | **Can be used for serology typing
75
Where are H antigens found?
Flagella
76
3 examples of pyrogenic cytokines?
TNF, IL-1, IL-6
77
What may fever cause in young children?
Convulsions/ seizures
78
Does direction does sepsis shifts haemostasic balance to? | But what may eventually happen?
Coagulation. Eventually clotting factors consumed --> hemorrhagic risk
79
Example of a Group A Strep (GAS)? | What type of haemolysis does it show?
S. pyogenes. | Beta
80
What haemolysis does S. pneumoniae show?
Alpha
81
What are 7 diseases that can be caused by S. pyogenes?
``` Strep throat Scarlet fever Cellulitis Necrotising fasciitis Puerperal (6 weeks after childbirth) sepsis Rheumatoid arthritis Glomerular nephritis ```
82
What is the coagulase, catalase and oxidase status of S. Aureus? How much NaCl can it tolerate?
Coagulase pos Catalase pos Oxidase neg Tolerates 15% NaCl
83
What kind of infections does S. Aureus commonly cause? (5)
``` Skin Soft tissue Wound Bone Joint ```
84
What kind of S. Aureus can cause food poisoning?
Only strains producing enterotoxins
85
How is MRSA usually acquired?
Nosocomial
86
Where is S. epidermidis usually found? | Coagulase???
Skin, mucous membrane | Coagulase neg
87
Where is S. Aureus usually found?
Nose, Perineum
88
How are infections from S. epidermidis acquired? Usually in who (2)?
Nosocomial. | Immuncompromised, those with foreign devices
89
Clostridium spp. is gram? | What is the O2 requirement and morphology?
Gram positive bacilli | Anaerobic
90
What is the mode of dissemination of clostridium spp.?
Spores
91
Where is clostrium spp. found? (2)
Normal bowel flora (thus in faeces) | Soil
92
What can clostridium perfringens cause?
Gas gangrene (after wound contamination)
93
What can clostridium tetani cause?
Tetanus (fatal paralysis)
94
What is Clostridiodes difficile associated with? Usually in who? What is the hallmark pathology? (2)
``` Antibiotic treatment (proliferates in altered bowel flora) Elderly Severe diarrhoea and pseudomembranous colitis ```
95
Does bacteraemia always show signs/ symptoms?
No. It just indicates a presence of bacteria in the blood. Sepsis will show signs/symptoms (Systemic, overwhelming inflammation)
96
Common bacteria causing UTI? (2)
E.Coli | Klebsiella
97
What are the 3 pathogenic clostridium spp.?
clostridium perfringens clostridium tetani clostridiodes difficile
98
What are the 2 a-haemolytic strep?
S. pneumoniae (Pneumonia, Meningitis) | S. viridans (Endocarditis)
99
What is Group B Strep associated with?
Neonatal meningitis
100
What are the non-haemolytic strep? What disease can it cause? Where is it usually found normally?
Enterococcus sp. UTI Gut commensal
101
What are 2 gram positive aerobic small bacilli?
``` Corynebacterium sp. (Diptheria) Listeria monocytogenes (meningitis) ```
102
What are 2 gram positive aerobic large bacilli?
``` Bacillus cereus (Food poisoning) Bacillus anthracis (Anthrax) ```
103
What are the gram positive and gram negative anaerobic bacilli?
Gram pos: Clostridium sp. | Gram neg: Bacteroides sp.
104
What are the 2 gram negative microaerophilic bacilli?
Small curved - campylobacter sp. | Spiral - Helicobacter sp.
105
What are the 2 gram negative aerobic bacilli? | Strict (2), Small (2), Large (1)
- Strict - Legionella sp Pseudomonas aeruginosa -Small- Bordetella pertussis (Whooping coigh) H. influenzae (COPD exacerbation) -Large- Coliforms
106
What is bacteriostatic and bactericidal?
Bacteriostatic - inhibits growth of bacteria | Bactericidal - kills
107
When the most of a drug does not bind to plasma protein (unbound/free), how does it influence Vd, Cl and T1/2?
Slower Cl | Higher Vd and T1/2
108
How are Abx usually excreted?
Urine (Renal) | Faeces (Hepatobiliary)
109
What is flucloxacillin used for?
Staph and strep skin infection | **NOT FOR MRSA!
110
What is the mode of excretion of penicillin and is it safe to use in pregnancy?
Renal (rapid). | Safe.
111
What is the side effect of penicllin?
Hypersensitivity/ allergic/ rash (cross-reactivity with across all penicillins and sometimes 5-10% cephalosporins)
112
What is an example of a 3rd generation cephalosporin?
Ceftriaxone
113
What does B-lactam target?
Irreversibly binds to Penicllin-binding protein. Resembles D-alanine D-alanine which is used for peptidoglycan cross-linking --> not processed --> halts cell wall synthesis --> cell lysis
114
What is the other component of Augmentin other than Amoxicillin? What is it used for?
Clavulanic acid. | B-lactamase inhibitor.
115
What are 2 examples of 1st gen cephalosporins? | What are they used for?
Cefazolin, Cefalexin. | For Strep and Staph
116
What is an example of a carbapenem? What is it used for? What is it resistant to?
Meropenem (Last resort for Gram neg) Hospital level infectious disease. Resistant to B-lactamase.
117
What are the 3 natural pencillins? What are their route of administration?
Benzylpenicillin/ Penicillin V - Oral Phenoxymethylpenicillin/ Penicillin G - IV Benzathine penicillin (Long-acting) - IM
118
What does Augmentin NOT cover?
MRSA and P. aeruginosa
119
How well is flucloxacillin absorbed in the GIT?
Not absorbed well
120
What is Tazocin made of? Route of administration? What does it not cover?
Piperacillin (extended spectrum against Gram Neg such as Pseudomonas) + Tazobactam (B-lactamase inhibitor). IV. MRSA.
121
What does Temocillin cover? | Route of administration?
``` Gram neg (coliforms), ESBL-producing organisms IV. ```
122
What is the mode of excretion of cephalosporins? Is it safe for pregnancy?
Urinary. | Safe.
123
Are pencillins or cephalosporins more resistant to B-lactamases?
Cephalosporins
124
What happens as the cephalosporin generations progress?
Spectrum extends **Also increases risk of C. diff infection
125
What does Vancomycin/ Teicoplanin target? (4)
Binds to end peptide chain (D-alanine D-alaine) of NAM and NAG of Peptidoglycan --> prevents further peptidoglycan synthesis Blocks PBP from accessing substrate Interfere with membrane and peptidoglycan precursor molecule Reduces cross-linking and activity of lytic enzyme s--> weaken cell wall
126
What does glycopeptide cover and not cover?
Only covers Gram pos. | No activity against Gram neg (cannot reach peptidoglycan due to outer membrane)
127
What happens to patients with kidney failure who are taking vancomycin?
Toxic blood accumulation thus further nephrotoxicity. **Renal excretion
128
Are most antibiotics that inhibit protein synthesis bacteriostatic or bactericidal? What is the exception?
Most are bacteriostatic (Reversible; protein synthesis resumes when Abx removed) Aminoglycosides irreversibly bind to 30S ribosome --> bactericidal
129
Why must Aminoglycosides be given IV (or IM)?
Not absorbed from gut
130
What does aminoglycosides cover? 1 common example of an aminoglycoside? Route of excretion? Side effects? (2) How are these prevented?
Gram neg aerobic organisms Gentamicin Renal Nephrotoxic and neurotoxic (to CN VIII - deafness, dizziness) --> monitor blood levels
131
What is the spectrum of tetracycline? What is it useful against? (2) What are the side effects (2) Who should it not be given to? (3)
Broad. Intracellular and atypical organisms (C. trachomatis) Increased secondary infections, stain and impair structure of bones and teeth Infants, children, pregnant women
132
What doxycycline be used to treat?
Lyme's disease due to its mild anti-inflammatory effect
133
What are macrolides used for (2)? Route of excretion? Polarity?
Intracellular pathogens and if there is penicillin allergy Hepatic Lipophillic (diffuses easily into cell)
134
Is erythromycin safe for pregnancy?
Yes
135
What are the Abx that binds to 30S ribosomal subunit?
Aminoglycosides | Tetracycline
136
What are the Abx that binds to 50S ribosomal subunit? What do they interfere with?
Macrolides Clindamycin (Lincosamides) Chloramphenicol Linezolid Translocation/ peptide bond formation
137
What is fusidic acid usually used for? | What does it block?
Superficial Staph skin infection (Topical) | Complexes with Elongation Factor-G to block peptide chain elongation
138
``` Is Metronidazole (Flagyl) bacteriostatic or bactericidal? What does it cover? How is the Abx activated? Side effects (3)? ```
Bactericidal Anaerobes, parasites/protozoa Partial reduction in cytosol --> toxic intermediate formation --> DNA strand breakage Disulfiram-like reaction with Alcohol, metallic taste, furred (white coat) tongue **Disulfiram is used to treat alcoholism - produces hangover like symptoms
139
``` Are fluoroquinolones (Levofloxacin, Ciprofloxacin) bacteriostatic or bactericidal? What does it cover? Mode of excretion? Side effects (1)? ```
Bactericidal Gram neg and some gram pos Renal C. difficile infection
140
What is the mode of action of quinolones (Nalidixic acid)?
Binds to DNA gyrase (Topoisomerase) -> prevents super-coiling -> indirectly inhibits DNA synthesis
141
What do Trimethoprim and sulfonamides inhibit? | Is the result bacteriostatic or bactericidal?
Folic acid synthesis | Bacteriostatic
142
What is the mode of action of sulfonamides?
Act as PABA analogues to competitively inhibit Dihydropteroate synthase
143
``` What does Trimethoprim inhibit? Why does it work better in bacteria? What does it cover? Mode of excretion? 1 disease it is commonly used to treat Often combined with? ```
``` Inhibits dihydrofolate reductase. Much higher affinity in bacteria. Some gram neg, some gram pos. Renal. Acute UTI. With Sulfamethoxazole --> Co-trimoxazole (Septrin). ```
144
What is folic acid used to synthesize? (4)
Thymidine, Purines, Methionine, Glycine
145
What is a side effect of Ciprofloxacin?
Tendinitis
146
As all Abx disrupts gut flora, can they affect the absorption of oral contraceptives?
Yes
147
Why are Abx sometimes given in combination (3)?
``` Prevent resistance (E.g. for TB) Synergistic effect Cover a broader range of organisms ```
148
Why should bacteriostatic and bactericidal Abx be used together?
NEVER COMBINE THESE 2 ABX TOGETHER! | Difficult to kill abx as metabolism of bacteria is slowed by static effects.
149
What are the 4 Cs that increases the risk of C. Difficile infection?
Cephalosporin Ciprofloxacin Co-amoxiclav Clindamycin
150
Can vancomycin be used against Lactobacillus?
No, it uses D-alanine D-LACTATE as side chain in cell wall
151
Why won't pencillin work against mycoplasma?
No cell wall
152
Why is vancomycin not effective against gram neg?
Outer membrane prevents entry
153
What condition is required for metronidazole to be taken up and activated?
Anaerobic condition
154
What are organisms that survive Abx tx known as? | How is its metabolism like?
Persistor cells (Not resistant but tolerant to treatment) - grow again when tx discontinued. Inert and slow-growing (thus not killed)
155
What can grow on catheters that is resistant to damage by Abx and host immunity?
Biofilms
156
High antibiotic use is associated with?
Abx resistance
157
What are the 2 types of genetic variation that may contribute to abx resistance?
1. Mutation (rapid growth -> mutation -> new variants) 2. Horizontal gene transfer - Transformation (uptake foreign genetic material from environment) - Transduction (bacteriophage) - Conjugation (plasmid, pili)
158
What are 4 mechanisms in which abx resistance can be acquired?
1. Altered permeability (Altered influx, Active efflux) 2. Inactivating enzymes (E.g. ESBL) 3. Replacement of sensitive pathway (E.g. resistant enzyme in folic acid pathway) 4. Altered target site (E.g. Staph PBP2a, Altered DNA gyrase)
159
Amino acid change in which 30S subunit will prevent Streptomycin from binding?
S12
160
Methylation of which 50S subunit will prevent erythromycin from binding?
25S
161
ESBL-producing organisms are resistant to which penicillins and which generation of cephalosporins? Which 2 Abx can overcome this?
All penicillins including monobactam and to 3rd gen cephalosporins. Cephamycin, Carbapenems
162
What is carbapenemase resistant to?
All penicillins, cephalosporins, carbapenems
163
What does colistin target? Side effects? When is it used?
Polymyxin Abx that targets outer membrane of Gram neg Nephrotoxic if given through injection Last resort for NDM-1 resistant bacteria (Metalloenzyme/ carbapenemase)
164
Why is it important to get rid of uncommon but resistant pathogens?
Can transfer plasmid to a more virulent strain
165
What is sub-therapeutic doses of Abx associated with?
Resistance, selects and allows for sub-resistant population of bacteria to grow
166
What virus has an icosahedral (20 faces) symmetry?
Adenovirus
167
What are the 7 steps of viral infection?
``` Attachment Binding to specific receptor Entry Un-coating Nucleic acid and protein synthesis Assembly Release ```
168
How do enveloped and non-enveloped virus enter host cells?
Enveloped - fusion of lipid membrane via viral enzyme -> capsid injected inside Non-enveloped - endocytosis
169
What is being used in viral nucleic acid and protein synthesis?
Viral enzymes (E.g. Proteases, RNA dependent RNA polymerase) and ALWAYS host ribosomes
170
How are enveloped and non-enveloped virus released from host cell?
Budding - human cell membrane fuses to make up the envelope when budding off Cell lysis - non-enveloped
171
What are 3 possible reasons for cell death to occur in a viral infection?
Lysis Hijacking of cell machinery Immune system
172
What cancer is Human Herpes Virus Type 8 associated with?
Kaposi's sarcoma
173
Can a virus spread even if a person is asymptomatic?
Yes
174
What are the 4 possible reasons for a positive detection of the virus but without any presenting symptoms?
1. Convalescent (resolving) 2. Late stage of incubation 3. Reactivation 4. Asymptomatic
175
Where can Torque Teno Virus be found?
In >90% adults worldwide but not associated with human pathogenicity
176
What study can be done to establish if a virus is a pathogen?
Case-control study
177
What are 3 components of the immune system against viral infection?
1. Cytotoxic T cells - detects non-human Ag on infected cells and induce apoptosis 2. Neutralising Ab (IgG, IgM) - stops infection/ re-infection 3. Innate immunity involving inducing IFN and TLR3 by viral DNA
178
What is the difference between NOTIFIABLE diseases, organisms and health-risk states?
Diseases - reported if suspected/ confirmed Organisms - may not always cause notifiable disease (E.g. Chicken pox disease is not notifiable but the virus VZV is notifiable) Heath risk states - Syndromes caused by serious, transmissible organisms (yet to be identified)
179
What does it mean when a virus has become quiescent? (5) | 2 examples of such virus.
Not actively replicating, dormant/ latent, asymptomatic, not infectious, can reactivate. HSV, VZV
180
HIV and Hep C can result in chronic infection for many years. How might this present?
Can be asymptomatic but still infectious for many years before life-threatening complications occur
181
How can viruses be detected in the lab? (2)
1. Ab response (Past vs current infection) | 2. Virus itself - PCR, Ag detection, //Obsolete// (cell culture, electron microscopy)
182
What can IgM and IgG titres of viral Ab suggest?
IgM - recent/ acute | IgG - chronic/ late/ past infection
183
When are paired blood samples for viral titre of IgG taken? | What difference should you expect?
During acute and convalescent phase. | IgG titres should have increased

Principles (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions