8.10 Virology

Question 1

Classification of viruses is made by:
A. Complement fixation serology
B. Election microscopy
C. Nucleic acid composition
D. Cellular inclusion bodies

Answer 1

C. Nucleic acid composition

Question 2

Which virus is the most common etiological agent of viral respiratory disease in infants and children?
A. Respiratory syncytial virus (RSV)
B. Measles virus
C. Coxsackie A virus
D. Coxsackie B virus

Answer 2

A. Respiratory syncytial virus (RSV)

Question 3

The most common viral syndrome of pericarditis, myocarditis, and pleurodynia (pain upon breathing) is caused by:
A. Herpes simplex virus (HSV)
B. Respiratory syncytial viral
C. Epstein-Barr virus (EBV)
D. Coxsackie B virus

Answer 3

D. Coxsackie B virus

Question 4

Which of the following viruses is implicated along with EBV as a cause of infectious mononucleosis?
A. Cytomegalovirus (CMV)
B. Coxsackie A virus
C. Coxsackie B virus
D. Hepatitis B virus

Answer 4

A. Cytomegalovirus (CMV)

Question 5

The most common causes of viral pneumonia in adults are:
A. Influenzae and adenovirus
B. Hepatitis A and B viruses
C. Coxsackie A and B viruses
D. Herpes simplex and CMV

Answer 5

A. Influenzae and adenovirus

Question 6

** Which virus belonging to the Reovirdae group causes gastroenteritis in infants and young children but an asymptomatic infection in adults?**
A. Coxsackie B virus
B. Rotavirus
C. Respiratory syncytial virus
D. Rhabdovirus

Answer 6

B. Rotavirus

Question 7

A very small, single-stranded DNA virus that causes a febrile illness with a rash, and is called the *fifth childhood disease after rubeola, rubella, varicella, and roseola is:
A. Rotavirus
B. Adenovirus type 40
C. Coxsackie A virus
D. Parvovirus B19

Answer 7

D. Parvovirus B19

Question 8

Hepatitis B virus can be transmitted by:
A. Acupuncture
B. Tattoos
C. Sexual contact
D. All of these options

Answer 8

D. All of these options

Question 9

Which virus has been implicated in adults gastroenteritis resulting from ingestion of contaminated food (especially shellfish) and water?
A. Noroviruses (Norwalk-like viruses)
B. Rotavirus
C. Hepatitis C virus
D. Coronavirus

Answer 9

A. Noroviruses (Norwalk-like viruses)

Question 10

Which virus is associated with venereal and respiratory tract warts and produces lesions of skin and mucous membranes?
A. Polyomavirus
B. Poxvirus
C. Adenovirus
D. Papillomavirus

Answer 10

D. Papillomavirus

Question 11

A clinical test used for the detection and identification of viral infections other than culture is:
A. Histology/cytology
B. Polymerase chain reaction/DNA probes
C. Serology
D. All of these options

Answer 11

D. All of these options

Question 12

Which technique is used for the confirmation of infection with HIV-1 and HIV-2?
A. Western blot (immunoblot) assay
B. ELISA
C. FDA-approved NAT
D. p24 Antigen testing

Answer 12

C. FDA-approved NAT

The Western blot assay is no longer used to confirm a positive serological test of antibodies to HIV. Western blot detects antibodies but it may miss people in the window phase of infection, is not confirmatory for neonatal infections because of the presence of maternal antibodies, and has a long turnaround time resulting in loss of contact with the patient. For these reasons, the CDC recommends a new approach using a simultaneous test for antibodies to both HIV-1 and HIV-2 and p24 antigen to screen for infection by immunoassay. Positive specimens would be tested by separate immunoassays to identify whether the infection is HIV-1 or HIV-2. Samples testing negative in suspected cases should be tested by a nucleic acid amplification method, such as PCR for viral RNA for definite identification.

Question 13

A 13-year-old boy was admitted to the hospital with diagnosis of viral encephalitis. History revealed that the boy harbored wild raccoons from nearby woods. What is the best method to determine if the boy has contracted rabies?
A. Remove the brainstem from all of the raccoons and examine for cytopathic effects
B. Request immunofluorescent test for antibody on the saliva from all of the raccoons.
C. Request immunofluorescent test for antigen in cutaneous nerve specimen obtained by nuchal biopsy.
D. Isolate the virus from the saliva of both the animals and the patient

Answer 13

C. Request immunofluorescent test for antigen in cutaneous nerve specimen obtained by nuchal biopsy.

Question 14

A 65-year-old woman was admitted to the hospital with acute respiratory distress, fever, myalgia, and headache. Influenzae A or B was suspected after ruling out bacteria pneumonia. Which of the following methods could be used to confirm influenza infection?
A. EIA
B. RT-PCR
C. Direct examination of nasal epithelium for virus using fluorescent antibody stain
D. All of these options

Answer 14

D. All of these options

Question 15

The most rapid definitive diagnosis of a genital herpes simplex (HSV-2) infection in a 20-year-old man is made by using which method?
A. Direct immunofluorescence test for viral antigen in vesicle fluid
B. Titer of serum and seminal fluid for antibodies to herpes simplex
C. Detection of anti-herpes simplex in seminal fluid
D. Cell culture of vesicle fluid

Answer 15

A. Direct immunofluorescence test for viral antigen in vesicle fluid

Question 16

A 20-year-old female college student complained of a sore throat and extreme fatigue. The physician noted lymphadenopathy and ordered a rapid test for infectious mononucleosis antibodies that was negative. Bacterial cultures were negative, as were serological tests for influenza A and B, HIV-1, CMV, hepatitis B, and antistreptolysin O. What would be the next line of viral testing to establish a diagnosis?
A. Herpes simplex
B. Rubella
C. Epstein-Barr
D. West Nile

Answer 16

C. Epstein-Barr

Question 17

A 60-year-old male gardener from New York State was hospitalized with flulike symptoms and was eventually diagnosed with encephalitis. While working in his garden, he had noticed several dead birds around his bird feeder. The region is known for heavy mosquito infestation. What is the most likely cause of his illness?
A. West Nile virus
B. Epstein-Barr virus
C. Parovirus
D. Hantavirus

Answer 17

A. West Nile virus

Question 18

**A 30-year-old male patient, who was a contractor and building inspector in the southwestern United States, complained of difficulty breathing and was admitted to the hospital with severe respiratory disease. The physician noted a high fever and cough.

Two days, earlier, the patient had inspected an old abandoned warehouse that was infested by rodents. The patient was given intravenous antibiotics, but 2 days into therapy, the pneumonia worsened, leading to pulmonary edema. Which organism should be suspected of causing his illness?**

A. Hantavirus
B. Rotavirus
C. West Nile virus
D. Norovirus (formerly Norwalk-like virus)

Answer 18

A. Hantavirus

Question 19

A 3-year-old female child was admitted to the hospital following a 2-day visit with relatives over the Christmas holidays. Vomiting and diarrhea left her severely dehydrated. No other members of the family were affected. All bacterial cultures proved negative. A stool sample should be tested for which virus?
A. CMV
B. EBV
C. Hepatitis D
D. Rotavirus

Answer 19

D. Rotavirus

Question 20

A 25-year-old male patient was diagnosed with HIV-1 by using enzyme immunoassay; the patient tested positive twice, and the diagnosis was confirmed with RT-PCR. Which laboratory test(s) should be performed prior to initiating antiviral therapy and for monitoring during antiviral therapy?
A. Quantitative plasma virus concentration (viral load testing)
B. Quantitation of CD4 lymphocytes
C. Phenotype/genotype resistance testing
D. All of these options

Answer 20

D. All of these options

Question 21

A 6-month-old male infant was hospitalized with a respiratory infection. He was diagnosed with apnea and bronchiolitis. Further testing revealed congenital heart disease. Bacterial cultures were negative for S. pneumoniae and H. influenzae. What viruses should be tested?
A. RSV
B. Rotavirus
C. Norovirus (Norwalk-like virus)
D. HIV

Answer 21

A. RSV

Question 22

A young male hunter encountered a fox in his path during a walk in the woods. The fox was staggering but appeared nonthreatening. The man tried to avoid contract but was attacked and bitten on the leg. The bite broke the skin but was not deep. Wildlife officials were unable to locate the fox for testing. What procedure should be performed next for the hunter?
A. Spinal tap with CSF testing for rabies virus (within 2 months)
B. Administration of hyperimmune antirabies globulin and rabies vaccine
C. Biopsy of the wound site
D. Throat culture and blood culture (weekly)

Answer 22

B. Administration of hyperimmune antirabies globulin and rabies vaccine

Question 23

A 40-year-old female presented with a respiratory infection after returning home from a visit to her homeland of China. Rapid onset of pneumonia in the lower respiratory area prompted the physician to place her in isolation. She was diagnosed presumptively with severe acute respiratory syndrome (SARS) and placed on a respirator. What type of testing should be done next to diagnose this disease?
A. RT-PCR
B. Latex agglutination test
C. Blood culture
D. Complement fixation

Answer 23

A. RT-PCR

Question 24

A 25-year-old pregnant female with genital lesions delivered a premature newborn with complications. The baby tested negative for bacterial infection (cultures of blood and urine). Antigen testing of the baby’s urine proved negative for group B streptococci and S. pneumoniae. The mother tested negative for bacterial sexually transmitted diseases (STDs) and for group B streptococci. The baby was treated with acyclovir but failed to survive. What was the most likely cause of death?
A. CMV
B. HIV
C. RSV
D. HSV

Answer 24

D. HSV

Question 25

A young father of two small children complained of a rash on the torso of his body. The children had been diagnosed with chickenpox and confined to their home. The father had experienced chickenpox as a child and knew he did not have the same rash as his children. What is the most likely cause of the father’s rash?
A. HSV 1
B. Varicella-zoster virus
C. HSV 2
D. EBV

Answer 25

B. Varicella-zoster virus

Question 26

The organs of a 65-year-old male were donated soon after a fatal auto accident. Three recipients of his corneas and kidneys died within weeks after receiving his organs. Which of the following viruses most likely caused the death of these recipients?
A. Human immunodeficiency virus
B. Rabies
C. Norovirus (Norwalk-like virus)
D. Rotavirus

Answer 26

B. Rabies

Question 27

While on a 7-day cruise to Vancouver and Alaska, a number of passengers reported to the ship’s medical staff complaining of vomiting and diarrhea. Which is the most likely virus to have infected these mainly adult passengers?
A. Rotavirus
B. Parainfluenza virus
C. Respiratory syncytial virus
D. Norovirus (Norwalk or Norwalk-like viruses)

Answer 27

D. Norovirus (Norwalk or Norwalk-like viruses)

Question 28

SITUATION: A patient tested positive for HIV-1 infection with use of a RT-PCR method. However, 1 week later, a second blood sample was collected and sent to a reference laboratory, which performed a confirmatory Western blot test. The Western blot test was negative. What best explains these results?
A. The samples for RT-PCR and Western blot were not from the same patient
B. RT-PCR is more sensitive for early detection
C. The RT-PCR result was falsely positive
D. The RT-PCR test detected HIV-2 and the Western blot is specific for HIV-1

Answer 28

B. RT-PCR is more sensitive for early detection

Question 29

SITUATION: A pregnant women was seen by her obstetrician with signs of flulike illness during her second trimester. NAT was ordered for Toxoplasma gondii, rubella, CMV, and HSV-1 and -2. All test results were negative. However, after delivery, the newborn exhibited signs of an infection and failed to survive. Which virus in the mother causes a 90% transplacental infection rate?
A. Hepatitis A
B. Hepatitis B
C. Hepatitis D
D. Hepatitis G

Answer 29

B. Hepatitis B

Question 30

An immunocompromised patient was admitted to the hospital with a diagnosis of hemorrhagic cystitis. Which combination of virus and specimen would be most appropriate to diagnose a viral cause of this disorder?
A. BK virus-urine
B. Human papilloma virus-skin
C. Hepatitis B virus-serum
D. Epstein-Barr virus-serum

Answer 30

A. BK virus-urine

Question 31

Which of the following genera and RNA viruses listed is the cause of viral hemorrhagic fever displaying many filamentous shapes, such as “U” or “6” and circular forms while being viewed under the electron microscope?
A. Filovirus-Ebola virus
B. Flavivirus-West Nile virus
C. Picornavirus-poliovirus
D. Toga virus-western equine encephalitis virus

Answer 31

A. Filovirus-Ebola virus

Question 32

Which of the following RNA flaviviruses is responsible for Guillain-Barré syndrome and birth defects of the brain (microcephaly, absent forehead, and triangular face shape) or poor outcomes in pregnant women and was first recognized in 2015 in Brazil?
A. West Nile virus
B. Hepatitis C virus
C. Zika virus
D. Dengue fever virus

Answer 32

C. Zika virus

Question 33

Which of the following diseases, which are spread through direct contact and aerosols of the (RNA) coronovirus genera, was transmitted to hospital workers who were caring for infected patients in China, causing a severe acute respiratory illness that led to a worldwide outbreak in 2002?
A. Severe acute respiratory syndrome (SARS)
B. Encephalitis
C. Gastroenteritis
D. Liver necrosis

Answer 33

A. Severe acute respiratory syndrome (SARS)

Question 34

A pregnant patient presented with symptoms similar to hepatitis A but tested negative. She had traveled to India most recently. Which of the following is the cause of a hepatitis infection with a high mortality rate (10%-20%) in pregnant women and is transmitted via the fecal-oral route?
A. Hepatitis B
B. Hepatitis E
C. Hepatitis C
D. Hepatitis D

Answer 34

B. Hepatitis E