Virus Quiz : Test your knowledge

1. Which of the following best describes a “virion”?

1. The viral genome integrated into the host chromosome.
2. The complete, infectious form of a virus particle outside a host cell.
3. The assembly of host ribosomes translating viral proteins.
4. The non-infectious precursor of a viral capsid.

2. In the replication cycle of many RNA viruses, the enzyme “RNA-dependent RNA polymerase” is essential because it:

1. Copies viral RNA from an RNA template.
2. Copies viral DNA from an RNA template.
3. Copies viral RNA from a DNA template.
4. Repairs host cell DNA damage caused by the virus.

3. Which of the following statements about “cytopathic effect” (CPE) in viral infections is/are correct?

1. It refers to structural changes in host cells due to viral infection.
2. It may include cell rounding, syncytia formation, or inclusion bodies.
3. It is observed only in bacterial cultures 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

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

1. It refers to the release of virus from an infected host into the environment.
2. It can occur through respiratory secretions, faeces, blood, or other body fluids.
3. It always stops as soon as clinical symptoms appear.

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

5. In many enveloped viruses, the matrix (or M) protein primarily:

1. Binds host antibodies and prevents neutralization.
2. Bridges the viral envelope and nucleocapsid, helping in virion assembly.
3. Synthesizes the viral genome inside the host nucleus.
4. Acts as a receptor on host cells for viral entry.

6. Which of the following statements correctly distinguishes “pandemic” from “epidemic” in relation to viral diseases?

1. An epidemic is confined to a community or region, while a pandemic involves worldwide or multi-continent spread.
2. An epidemic refers only to vector-borne viruses; a pandemic only to respiratory viruses.
3. An epidemic implies higher case fatality than a pandemic.
4. An epidemic cannot involve new viral strains; a pandemic always does.

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

1. A reservoir is a habitat where the virus normally lives and multiplies.
2. Reservoirs may be humans, animals, or environmental sources.
3. Vectors are always the same as reservoirs.

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

8. In public health response to a new viral outbreak, “non-pharmaceutical interventions” (NPIs) include all of the following, EXCEPT:

1. Physical distancing and mask use.
2. Closure of schools and mass gatherings.
3. Use of antiviral drugs to treat confirmed cases.
4. Hand hygiene and respiratory etiquette promotion.

9. Which of the following is the most appropriate definition of “attack rate” in an outbreak of a viral disease?

1. Number of deaths divided by total population at risk.
2. Number of new cases among population at risk during a specified period, divided by the total population at risk.
3. Total number of existing cases at a point in time divided by total population.
4. Number of new cases divided by number of recovered cases.

10. For a viral disease transmitted primarily by respiratory droplets, which of the following measures directly reduces the probability of transmission per contact?

1. Wearing well-fitted face masks.
2. Reducing the number of social contacts.
3. Shortening the infectious period through early isolation.
4. Switching from in-person to online gatherings.