Laboratory: Diagnostic Virology

Question 1

Purposes of Viral Laboratory Studies

Answer 1

Confirm the diagnosis by identifying the viral agent of infection
Define the disease process
Monitor the disease epidemiologically
Educate physicians and patients

Question 2

Commonly used swab

Answer 2

Dacron or rayon

Question 3

Inhibit the replication of some viruses & interfere NAAT

Answer 3

Calcium alginate swabs

Question 4

At what temperature does VTM form ice crystals?

Answer 4

-20 degrees Celsius

Question 5

Ideal temperature of VTM when delayed for 4-7 days?

Answer 5

-70 degrees Celsius

Question 6

Antibacterial and antifungal agents are added to
transport systems to?

Answer 6

Inhibit contaminating microorganisms

Question 7

Samples that should be collected without viral transport
media include:

Answer 7

Blood, bone marrow, CSF, amniotic fluid, urine, pericardial fluid, and pleural fluid

Question 8

In collecting BAL, saline is injected in?

Answer 8

Subsegmental bronchus

Question 9

In collecting BW, saline is injected in?

Answer 9

Segmental bronchus

Question 10

In collecting buccal swab, _ gland is massaged for _ seconds and swab is performed at the buccal mucosa near _

Answer 10

Parotid
30
Stensen’s duct

Question 11

1st swab in cervical swab is for removing _ and is discarded

Answer 11

Cervical mucus/exudates

Question 12

2nd swab in cervical swab is used to collect _

Answer 12

Epithelial cells

Question 13

CSF is collected at least _ mL into a sterile container

Answer 13

2 mL

Question 14

Swab used for conjunctiva is moistened with?

Answer 14

Sterile physiologic saline

Question 15

In collecting lesions swab, you should select _ lesion with _ fluid and clean exterior with _

Answer 15

Non-crusted
Clear
Sterile saline

Question 16

Fluid from lesions can be aspirated with _

Answer 16

26-30 gauge tuberculin needle

Question 17

Number of virions shed from the lesion decreases
dramatically each day after the lesion manifests. True or False?

Answer 17

True

Question 18

In NP swab, a swab with _ is inserted into _ nasopharynx

Answer 18

Flexible metal shaft
Posterior

Question 19

In rectal swab, use of _ is not encouraged

Answer 19

Lubricant

Question 20

What type of swab is preferred in stool and rectal swab?

Answer 20

Culturette swab

Question 21

Diagnostic method with excellent sensitivity and specificity

Answer 21

Molecular diagnostics

Question 22

Diagnostic method with maximum specificity

Answer 22

Culture

Question 23

Diagnostic method characterized by its speed of diagnosis

Answer 23

Antigen detection

Question 24

Diagnostic method that assesses immunity

Answer 24

Serology

Question 25

Not sensitive as culture methods; offer quick results to allow for rapid therapy

Answer 25

Direct Viral Detection

Question 26

What type of microscope is used in DVD?

Answer 26

Electron microscope

Question 27

In immunologic Detection of Viral Antigen, what assay is used?

Answer 27

Enzyme immunoassay

Question 28

Rarely used in clinical laboratories; suitable for large teaching or research institutions

Answer 28

Electron Microscopy

Question 29

Used to visualize inclusion bodies; observes cytopathic effect (CPE) in cell cultures

Answer 29

Bright field Light Microscopy

Question 30

Dense aggregates of stainable substances of viruses, usually proteins; produced due to developmental / maturation process of virus or in some viruses seen only after viral multiplication

Answer 30

Inclusion Bodies

Question 31

Intracytoplasmic inclusion bodies in Rabies

Answer 31

Negri bodies

Question 32

Intracytoplasmic inclusion bodies in Smallpox

Answer 32

Guarnieri bodies

Question 33

Intracytoplasmic inclusion bodies in Fowl pox

Answer 33

Bollinger bodies

Question 34

Intracytoplasmic inclusion bodies in Mollascum contagiosum

Answer 34

Henderson-Peterson bodies

Question 35

Guarnieri bodies are also known as?

Answer 35

Paschen bodies

Question 36

Herpes simplex and VZV is classified as what type?

Answer 36

Cowdry Type A

Question 37

Infection with poliovirus is classified as what type?

Answer 37

Cowdry Type B

Question 38

Herpes simplex and VZV has what intranuclear inclusion?

Answer 38

Lipschutz inclusions

Question 39

Yellow fever has what intranuclear inclusion?

Answer 39

Torres Bodies

Question 40

Measles has what kind of inclusion?

Answer 40

Warthin-Finkeldey bodies

Question 41

CMV has what kind of appearance?

Answer 41

Owl's eye

Question 42

Cells from a patient are fixed to a microscope slide; fluorescence-labeled antibodies are added

Answer 42

Immunofluorescence Microscopy (DFA Assays)

Question 43

Positive reaction in DFA assays

Answer 43

Labeled antibody will bind and fluoresce

Question 44

These assays enable the diagnosis of some viruses within 10-30 minutes

Answer 44

Rapid Antigen Assays

Question 45

Obtained from animal tissue

Answer 45

Primary Cell Cultures

Question 46

Cell lines can divide; diploid cells

Answer 46

Finite Cell Cultures

Question 47

Capable of infinite passage; heteroploid

Answer 47

Continuous Cell Cultures

Question 48

Cell culture with greater sensitivity

Answer 48

Mixed Cells Culture

Question 49

PMK cells means?

Answer 49

Primary Monkey Kidney cells

Question 50

PMK cells are under what type of cell culture?

Answer 50

Primary Cell Cultures

Question 51

Human neonatal lung cells are under what type of cell culture?

Answer 51

Finite Cell Cultures

Question 52

Hep2, A549 and Vero are under what type of cell culture?

Answer 52

Continuous Cell Cultures

Question 53

What virus reacts positively with rabbit kidney?

Answer 53

Herpes simplex virus

Question 54

All viruses have positive reaction with what cell culture?

Answer 54

Human diploid fibroblasts (HDF)

Question 55

Herpes simplex virus only reacts negatively with?

Answer 55

Primary monkey kidney cells

Question 56

CMV only reacts positively with?

Answer 56

HDF

Question 57

Enterovirus and Adenovirus only reacts negatively with?

Answer 57

Rabbit kidney

Question 58

CPE of Herpes simplex virus

Answer 58

Large rounded cells

Question 59

CPE of CMV

Answer 59

Large rounded cells

Question 60

CPE of VZV

Answer 60

Foci or rounded cells; possible synctia

Question 61

CPE of Enterovirus

Answer 61

Refractile; round cells in clusters

Question 62

CPE of Adenovirus

Answer 62

Large rounded cells in clusters

Question 63

CPE of Respiratory synctial virus

Answer 63

Synctia

Question 64

CPE of Influenza, parafluenza

Answer 64

Variable - none to to granular appearance

Question 65

Most commonly used in virus cultivation

Answer 65

Rabbit Guinea pig Mouse Rat

Question 66

Certain _ viruses require _ for isolation of the virus

Answer 66

Coxsackie A Suckling mice

Question 67

Rarely used for virus cultivation

Answer 67

Embryonated eggs

Question 68

Modified cell culture; rapid detection of viruses in vitro

Answer 68

Centrifugation-Enhanced Shell Vial Culture

Question 69

Morphological change produced by the virus in the cell line

Answer 69

Cytopathic Effect (CPE)

Question 70

Growth of the first virus inhibit by the second virus

Answer 70

Viral Interference

Question 71

DFA assays uses _ counterstain that can be seen as _ fluorescence in the background

Answer 71

Evans Blue Red

Question 72

Green fluorescence indicated what in DFA assays?

Answer 72

Antigen is detected

Question 73

Utilizes PCR or nucleic acid probes

Answer 73

Viral Genes Detection

Question 74

Detects circulating antibodies to viruses after exposure.

Answer 74

Serologic Assays

Question 75

Serologic assays directly detects the virus rather than measure the host response. True or False?

Answer 75

False, serological assays measure the host response rather than detecting the virus