Virus Quiz : Test your knowledge

1. Which of the following best explains why some viral infections remain localized while others become systemic?

1. Only systemic viruses have nucleic acids.
2. Ability of the virus to spread via lymphatics or bloodstream from the site of entry.
3. Localized viruses are always non-enveloped.
4. Systemic spread requires an arthropod vector in all cases.

2. With reference to “neurotropic” viruses, which of the following is/are correct?

1. They show a special affinity for nervous tissue.
2. They may reach the central nervous system by neuronal or haematogenous spread.
3. They are always non-pathogenic in humans.

Select the correct answer using the code below:

1. 1 only
2. 1 and 2 only
3. 2 and 3 only
4. 1, 2 and 3

3. The term “abortive infection” in virology refers to:

1. Infection that leads to massive virion production and host death.
2. Infection in which the virus enters the cell but fails to complete replication.
3. Infection always confined to arthropod vectors.
4. Infection that results only in chronic carrier state.

4. With reference to “viral inclusion bodies”, which of the following statements is/are correct?

1. They are microscopic aggregates seen in infected cells.
2. They may represent sites of viral replication or assembly.
3. They are found only in bacterial infections and not in viral infections.

Select the correct answer using the code below:

1. 1 only
2. 1 and 2 only
3. 2 and 3 only
4. 1, 2 and 3

5. “Vertical transmission” of a virus refers to spread:

1. From one geographic region to another via travellers.
2. From parent to offspring, e.g., transplacental, perinatal or via breast milk.
3. Only through arthropod vectors between animals.
4. Exclusively via contaminated water sources.

6. In a viral infection, a “primary viremia” is best defined as:

1. The first phase of virus in the blood following initial replication at the entry site.
2. The presence of virus in blood after widespread organ involvement.
3. The presence of neutralizing antibodies in the bloodstream.
4. The total viral genome copies in a tissue biopsy.

7. With reference to viral “pathogenicity” and “virulence”, which of the following is/are correct?

1. Pathogenicity refers to the ability of a virus to cause disease.
2. Virulence refers to the degree of severity of the disease caused.
3. Two strains of the same virus can differ in virulence.

Select the correct answer using the code below:

1. 1 and 2 only
2. 1 and 3 only
3. 2 and 3 only
4. 1, 2 and 3

8. In diagnosing acute viral infections, paired serum samples (acute and convalescent) are used mainly to:

1. Measure the change in antibody titre over time.
2. Detect only viral nucleic acid directly.
3. Assess liver function exclusively.
4. Confirm presence of bacterial co-infection.

9. Which of the following best describes “nosocomial” viral infections?

1. Infections acquired in community settings only.
2. Infections acquired in a hospital or healthcare setting and not present at the time of admission.
3. Infections transmitted solely by vectors in rural areas.
4. Infections occurring only in laboratory workers.

10. For a viral disease controlled primarily by vaccination, which of the following situations most strongly signals risk of re-emergence?

1. Consistently high vaccination coverage above herd immunity threshold.
2. Progressive decline in vaccine uptake in successive birth cohorts.
3. Stable population with no change in birth rate.
4. Improved cold-chain facilities for vaccines.