Question 1

Varicella-zoster virus, Epstein-Barr virus, and cytomegalovirus are included in this widely disseminated group of viruses.

Accepted Answer

A) Coronaviruses 
B) Herpes viruses 
C) Caliciviruses 
D) Filoviruses 
A) Coronaviruses 
B) Herpes viruses 
C) Caliciviruses 
D) Filoviruses B

Question 2

The test of choice for use with CSF to diagnose aseptic meningitis caused by enterovirus is

Accepted Answer

A) cell culture. 
B) PCR. 
C) antigenemia immunoassay. 
D) shell vial assay. 
A) cell culture. 
B) PCR. 
C) antigenemia immunoassay. 
D) shell vial assay. B

Question 3

During viral assembly, viral envelopes are acquired

Accepted Answer

A) by production of envelope constituents by host cellular DNA. 
B) as the virion buds from a host cell membrane. 
C) through replication of viral nucleic acid. 
D) as host cell lysis produces many membrane fragments. 
A) by production of envelope constituents by host cellular DNA. 
B) as the virion buds from a host cell membrane. 
C) through replication of viral nucleic acid. 
D) as host cell lysis produces many membrane fragments. B

Question 4

The term antigenic drift refers to

Accepted Answer

A) mutation during genome replication resulting in minor antigenic change and relatively mild influenza outbreaks every 1 to 3 years. 
B) reassortment of the segmented viral genome during co-infection in nonhuman animals, resulting in major antigenic change and periodic worldwide outbreaks. 
C) what happens when human virus infects a cell at the same time as an animal influenza virus. 
D) All of the above are correct. 
A) mutation during genome replication resulting in minor antigenic change and relatively mild influenza outbreaks every 1 to 3 years. 
B) reassortment of the segmented viral genome during co-infection in nonhuman animals, resulting in major antigenic change and periodic worldwide outbreaks. 
C) what happens when human virus infects a cell at the same time as an animal influenza virus. 
D) All of the above are correct.

Question 5

Tzanck smears are prepared by

Accepted Answer

A) pressing a microscope slide against the base of an ulcer to collect infected and noninfected cells. 
B) aspirating a small "drop" of vesicle fluid and smearing this onto a microscope slide. 
C) removing vesicle fluid by dabbing with a sterile gauze and then smearing this onto a microscope slide. 
D) collecting fecal sample with a swab and rolling the swab onto a microscope slide. 
A) pressing a microscope slide against the base of an ulcer to collect infected and noninfected cells. 
B) aspirating a small "drop" of vesicle fluid and smearing this onto a microscope slide. 
C) removing vesicle fluid by dabbing with a sterile gauze and then smearing this onto a microscope slide. 
D) collecting fecal sample with a swab and rolling the swab onto a microscope slide.

Question 6

Immune status tests are used to

Accepted Answer

A) identify patients who have been infected by a virus in the past. 
B) identify patients who have been vaccinated for a virus in the past. 
C) identify the presence of lifelong immunity to reinfection of a virus. 
D) All of the above are correct. 
A) identify patients who have been infected by a virus in the past. 
B) identify patients who have been vaccinated for a virus in the past. 
C) identify the presence of lifelong immunity to reinfection of a virus. 
D) All of the above are correct.

Question 7

Viruses can be stored by

Accepted Answer

A) freezing at 20°C. 
B) freezing in liquid nitrogen. 
C) inoculating to continuous cell lines such as HEp-2. 
D) refrigeration at 2° to 6°C. 
A) freezing at 20°C. 
B) freezing in liquid nitrogen. 
C) inoculating to continuous cell lines such as HEp-2. 
D) refrigeration at 2° to 6°C.

Question 8

Lip and genital specimens are most likely collected for the detection of

Accepted Answer

A) varicella zoster virus. 
B) herpes simplex virus. 
C) cytomegalovirus. 
D) rotavirus. 
A) varicella zoster virus. 
B) herpes simplex virus. 
C) cytomegalovirus. 
D) rotavirus.

Question 9

Viral capsids are composed of many individual subunits called

Accepted Answer

A) capsomeres. 
B) virions. 
C) capsules. 
D) nucleocapsids. 
A) capsomeres. 
B) virions. 
C) capsules. 
D) nucleocapsids.

Question 10

Concerning the two immunofluorescence methods of diagnosing viral infection, which statement is correct?

Accepted Answer

A) Direct immunofluorescence is generally more rapid and specific than indirect immunofluorescence. 
B) Indirect immunofluorescence is best suited to situations in which large quantities of virus are suspected. 
C) Signal amplification of the direct test decreases specificity by increasing nonspecific background fluorescence. 
D) High-quality monoclonal antibodies improve the sensitivity and specificity of the direct test. 
E) All of the above are correct. 
A) Direct immunofluorescence is generally more rapid and specific than indirect immunofluorescence. 
B) Indirect immunofluorescence is best suited to situations in which large quantities of virus are suspected. 
C) Signal amplification of the direct test decreases specificity by increasing nonspecific background fluorescence. 
D) High-quality monoclonal antibodies improve the sensitivity and specificity of the direct test. 
E) All of the above are correct.

Question 11

Cytomegalovirus can be detected in clinical specimens using

Accepted Answer

A) cell culture. 
B) shell vial assay. 
C) antigenemia immunoassay. 
D) All of the above are correct. 
A) cell culture. 
B) shell vial assay. 
C) antigenemia immunoassay. 
D) All of the above are correct.

Question 12

Long-term storage of a specimen for viral culture for more than 6 days should include

Accepted Answer

A) holding specimen at 4°? C. 
B) holding specimen at -70° C. 
C) diluting or emulsifying in viral transport medium and holding at -70° C. 
D) holding specimen at 20° C. 
A) holding specimen at 4°? C. 
B) holding specimen at -70° C. 
C) diluting or emulsifying in viral transport medium and holding at -70° C. 
D) holding specimen at 20° C.

Question 13

The term blind passage in virology

Accepted Answer

A) refers to a technique that is less frequently used today because of the added time and expense involved. 
B) describes a technique that is used to detect viruses that may not produce cytopathic effects (CP
E)  in the initial culture tube but will when the "beefed-up" inoculum is passed to a second tube. 
C) describes a technique that can be used to dilute toxicity and thus prevent ambiguous CPE caused by toxicity. 
D) describes a technique that is performed by scraping the monolayer off the sides of the tube and inoculating 0.25 mL of the resulting suspension into a new cell culture. 
E) All of the above are correct. 
A) refers to a technique that is less frequently used today because of the added time and expense involved. 
B) describes a technique that is used to detect viruses that may not produce cytopathic effects (CP
E)  in the initial culture tube but will when the "beefed-up" inoculum is passed to a second tube. 
C) describes a technique that can be used to dilute toxicity and thus prevent ambiguous CPE caused by toxicity. 
D) describes a technique that is performed by scraping the monolayer off the sides of the tube and inoculating 0.25 mL of the resulting suspension into a new cell culture. 
E) All of the above are correct.

Question 14

Concerning the two immunofluorescence methods of diagnosing viral infection, which statement is correct?

Accepted Answer

A) Direct immunofluorescence is generally more rapid and specific than indirect immunofluorescence. 
B) Direct immunofluorescence is best suited to situations in which large quantities of virus are suspected. 
C) Signal amplification of the indirect test decreases specificity by increasing nonspecific background fluorescence. 
D) Indirect immunofluorescence should be used when lower quantities of virus are suspected, such as for detection of respiratory viruses in specimens from adult patients. 
E) All of the above are correct. 
A) Direct immunofluorescence is generally more rapid and specific than indirect immunofluorescence. 
B) Direct immunofluorescence is best suited to situations in which large quantities of virus are suspected. 
C) Signal amplification of the indirect test decreases specificity by increasing nonspecific background fluorescence. 
D) Indirect immunofluorescence should be used when lower quantities of virus are suspected, such as for detection of respiratory viruses in specimens from adult patients. 
E) All of the above are correct.

Question 15

The protein coat that surrounds the nucleic acid of a virion is called a

Accepted Answer

A) capsomere. 
B) capsid. 
C) capsule. 
D) nucleocapsid. 
A) capsomere. 
B) capsid. 
C) capsule. 
D) nucleocapsid.

Question 16

When testing for antiviral IgM antibody, false-negative results may occur when

Accepted Answer

A) rheumatoid factor combines with homologous or virus-specific IgG present in the patient specimen. 
B) high levels of strongly binding homologous IgG antibodies prevent binding of IgM molecules. 
C) antibody-Fc receptors occur in cells infected with virus. 
D) All of the above are correct. 
A) rheumatoid factor combines with homologous or virus-specific IgG present in the patient specimen. 
B) high levels of strongly binding homologous IgG antibodies prevent binding of IgM molecules. 
C) antibody-Fc receptors occur in cells infected with virus. 
D) All of the above are correct.

Question 17

The term syncytia is used to describe

Accepted Answer

A) the ability of virions to synchronize penetration and release from host cells. 
B) multinucleated cells formed from the fusion between cells penetrated by virions and other host cells nearby. 
C) the attraction of viral particles to specific tissue types within the host. 
D) the attachment of viral particles to certain transmitting molecules like blood cells to enable infectious spreading of the virus. 
A) the ability of virions to synchronize penetration and release from host cells. 
B) multinucleated cells formed from the fusion between cells penetrated by virions and other host cells nearby. 
C) the attraction of viral particles to specific tissue types within the host. 
D) the attachment of viral particles to certain transmitting molecules like blood cells to enable infectious spreading of the virus.

Question 18

A large, diverse group of viruses, most of which are transmitted by mosquitoes, which includes the deadly Hantavirus is called

Accepted Answer

A) coronaviruses. 
B) bunyaviruses. 
C) caliciviruses. 
D) filoviruses. 
A) coronaviruses. 
B) bunyaviruses. 
C) caliciviruses. 
D) filoviruses.

Question 19

A drawback with ELISAs is

Accepted Answer

A) that they are not well suited for high-volume testing or for when rapid results are needed. 
B) the inability of the technologist to make specimen quality evaluations from assessment of the number of cells present. 
C) that they cannot be performed by those with minimum training. 
D) that they do not include vials of positive and negative sera for quality monitoring of test procedures. 
A) that they are not well suited for high-volume testing or for when rapid results are needed. 
B) the inability of the technologist to make specimen quality evaluations from assessment of the number of cells present. 
C) that they cannot be performed by those with minimum training. 
D) that they do not include vials of positive and negative sera for quality monitoring of test procedures.

Question 20

Advantage of the shell vial culture over conventional cell culture for virus is that

Accepted Answer

A) virus is detected more quickly using the shell vial technique. 
B) inoculated shell vials can be stored for up to 9 weeks before use for viral culture. 
C) CPE is more easily interpreted. 
D) centrifugation is not necessary for optimal detection. 
E) All of the above are correct. 
A) virus is detected more quickly using the shell vial technique. 
B) inoculated shell vials can be stored for up to 9 weeks before use for viral culture. 
C) CPE is more easily interpreted. 
D) centrifugation is not necessary for optimal detection. 
E) All of the above are correct.

Exam 48: Laboratory Methods in Basic Virology

Varicella-zoster virus, Epstein-Barr virus, and cytomegalovirus are included in this widely disseminated group of viruses.

The test of choice for use with CSF to diagnose aseptic meningitis caused by enterovirus is

During viral assembly, viral envelopes are acquired

The term antigenic drift refers to

Tzanck smears are prepared by

Immune status tests are used to

Viruses can be stored by

Lip and genital specimens are most likely collected for the detection of

Viral capsids are composed of many individual subunits called

Concerning the two immunofluorescence methods of diagnosing viral infection, which statement is correct?

Cytomegalovirus can be detected in clinical specimens using

Long-term storage of a specimen for viral culture for more than 6 days should include

The term blind passage in virology

Concerning the two immunofluorescence methods of diagnosing viral infection, which statement is correct?

The protein coat that surrounds the nucleic acid of a virion is called a

When testing for antiviral IgM antibody, false-negative results may occur when

The term syncytia is used to describe

A large, diverse group of viruses, most of which are transmitted by mosquitoes, which includes the deadly Hantavirus is called

A drawback with ELISAs is

Advantage of the shell vial culture over conventional cell culture for virus is that

Microbial Taxonomy

Bacterial Genetics Metabolism and Structure

Host-Microorganism Interactions

Laboratory Safety

Specimen Management

Role of Microscopy

Traditional Cultivation and Identification

Nucleic Acid-Based Analytic Methods for Microbial Identification and Characterization

Immunochemical Methods Used for Organism Detection

Serologic Diagnosis of Infectious Diseases

Principles of Antimicrobial Action Resistance

Laboratory Methods and Strategies for Antimicrobial Susceptibility Testing

Staphylococcus, Micrococcus, and Similar Organisms

Streptococcus, Enterococcus, and Similar Organisms

Bacillus and Similar Organisms

Listeria, Corynebacterium, and Similar Organisms

Erysipelothirix, Lactobacillus, and Similar Organisms

Nocardia, Streptomyces, Rhodococcus, Oerskovia, and Similar Organisms

Enterobacteriaceae

Acinetobacter, Stenotrophomonas, and Other Organisms

Pseudomonas, Burkholderia, and Similar Organisms

Achromobacter, Rhizobium, Ochrobactrum, and Similar Organisms

Chryseobacterium, Sphingobacterium, and Similar Organisms

Alcaligenes, Bordetella Nonpertussis, Comamonas, and Similar Organisms

Vibrio, Aeromonas, Plesiomonas Shigelloides, and Chromobacterium Violaceum

Sphingomonas Paucimobilis and Similar Organisms

Moraxella

Eikenella Corrodens and Similar Organisms

Pasteurella and Similar Organisms

Actinobacillus, Kingella, Cardiobacterium, Capnocytophaga, and Similar Organisms

Haemophilus

Bartonella and Afipia

Campylobacter, Arcobacter, and Helicobacter

Legionella

Brucella

Bordetella Pertussis and Bordetella Parapertussis

Francisella

Streptobacillus Moniliformis and Spirillum Minus

Neisseria and Moraxella Catarrhalis

Overview and General Considerations

Laboratory Considerations

Mycobacteria

Obligate Intracellular and Nonculturable Bacterial Agents

Cell Wall-Deficient Bacteria: Mycoplasma and Ureaplasma

The Spirochetes

Laboratory Methods for Diagnosis of Parasitic Infections

Laboratory Methods in Basic Mycology

Bloodstream Infections

Infections of the Lower Respiratory Tract

Upper Respiratory Tract Infections and Other Infections of the Oral Cavity and Neck

Meningitis and Other Infections of the Central Nervous Systems

Infections of the Eyes, Ears, and Sinuses

Infections of the Urinary Tract

Genital Tract Infections

Gastrointestinal Tract Infections

Skin, Soft Tissue, and Wound Infections

Normally Sterile Body Fluids, Bone and Bone Marrow, and Solid Tissues

Laboratory Physical Design, Management, and Organization

Quality in the Clinical Microbiology Laboratory