Question 1

Which of the following best explains why a vaccine for the common cold is not feasible?

Accepted Answer

There are over 200 different viruses that can cause the common cold, making it difficult to target all with a single vaccine.

Question 2

Which symptom is LEAST likely to be associated with the common cold?

Accepted Answer

Fever

Question 3

Why are antibiotics ineffective in treating the common cold?

Accepted Answer

Antibiotics only target bacterial infections, not viral infections like the common cold.

Question 4

Which of the following is a key structural feature of the influenza virus?

Accepted Answer

Eight RNA segments and an outer lipid bilayer

Question 5

What is the primary function of the hemagglutinin (HA) spike on the influenza virus?

Accepted Answer

Attachment to host cell receptors

Question 6

Swine are considered 'mixing vessels' for new influenza strains because:

Accepted Answer

They can be infected by avian, swine, and human influenza viruses, allowing genetic reassortment.

Question 7

Which process leads to major changes in the influenza virus genome, potentially causing pandemics?

Accepted Answer

Antigenic shift

Question 8

A patient is treated with oseltamivir (Tamiflu) for influenza. What is the mechanism of action of this drug?

Accepted Answer

Inhibits neuraminidase, preventing release of new viral particles

Question 9

Which of the following statements about HIV-1 and HIV-2 is correct?

Accepted Answer

HIV-1 is related to viruses that infect chimpanzees and gorillas and accounts for the majority of cases worldwide.

Question 10

Which glycoprotein on HIV is responsible for binding to the CD4 receptor on host cells?

Accepted Answer

gp120

Question 11

During HIV infection, what is the significance of the provirus state?

Accepted Answer

It enables the virus to remain latent and evade immune detection.

Question 12

Which phase of HIV infection is characterized by a CD4+ T cell count below 200 cells/μl and the development of AIDS-defining conditions?

Accepted Answer

Phase 3

Question 13

Why is it challenging to develop an effective HIV vaccine?

Accepted Answer

There is no model of natural immunity to mimic and HIV mutates rapidly.

Question 14

Which diagnostic method is used to detect plasma viral load (PVL) in HIV patients?

Accepted Answer

PCR to detect viral RNA

Question 15

A patient with HIV is prescribed a combination of drugs including integrase inhibitors, protease inhibitors, and maturation inhibitors. What is the rationale for this approach?

Accepted Answer

To target multiple stages of the HIV life cycle and reduce the risk of drug resistance.

Question 16

Which population is most susceptible to rapid progression of HIV infection?

Accepted Answer

Older adults and young children

Question 17

Which of the following is NOT a route of HIV transmission?

Accepted Answer

Casual contact such as hugging or sharing towels

Question 18

What is the main function of cytotoxic T lymphocytes (CTLs) in HIV infection?

Accepted Answer

Suppress viral numbers by killing infected cells

Question 19

Which equation best represents the calculation of CD4+ T cell count per microliter ($\mu l$) in a blood sample?

Accepted Answer

$CD4^+\ T\ cell\ count = \frac{	ext{Number of CD4}^+\ 	ext{cells detected}}{	ext{Volume of blood in } \mu l}$

Question 20

Which of the following strategies is most effective in preventing HIV transmission in a population?

Accepted Answer

Discouraging sexual promiscuity and promoting condom use

Viral Disease Examples: Common Cold, Influenza, and HIV/AIDS (MBY161 Theme 12)

Study Guide - Practice Questions

Study Guide - Flashcards