$$\text{Sensitivity} = \frac{\text{True Positives}}{\text{True Positives} + \text{False Negatives}}$$

Question 1

Which of the following best describes the principle behind herd immunity?

Accepted Answer

It occurs when enough individuals are immune to a disease, reducing its spread even among those not immune.

Question 2

A patient receives a live attenuated vaccine. Which of the following is a primary advantage of this type of vaccine?

Accepted Answer

It induces a strong and long-lasting immune response, often with a single dose.

Question 3

Which equation correctly represents the calculation of sensitivity for a diagnostic test?

Accepted Answer

$$	ext{Sensitivity} = \frac{	ext{True Positives}}{	ext{True Positives} + 	ext{False Negatives}}$$

Question 4

Which of the following best explains why adjuvants are added to vaccines?

Accepted Answer

To enhance the immune response to the antigen.

Question 5

A diagnostic test has a specificity of 95%. What does this mean?

Accepted Answer

95% of people without the disease will test negative.

Question 6

Which of the following is a disadvantage of inactivated vaccines compared to live attenuated vaccines?

Accepted Answer

They often require multiple doses to achieve effective immunity.

Question 7

A patient’s serum is tested for antibodies using an agglutination assay. The titer is rising over several days. What does this most likely indicate?

Accepted Answer

The patient is experiencing an active infection.

Question 8

Which of the following best describes a conjugated vaccine?

Accepted Answer

A vaccine where a polysaccharide antigen is linked to a protein to enhance immunogenicity.

Question 9

Which of the following is a key benefit of ELISA (Enzyme-Linked Immunosorbent Assay) in diagnostics?

Accepted Answer

It provides quantitative results and is highly sensitive.

Question 10

Which of the following statements about monoclonal antibodies is correct?

Accepted Answer

They are produced by fusing B cells with myeloma cells to create hybridomas.

Question 11

Which of the following best describes the mechanism of a toxoid vaccine?

Accepted Answer

It uses inactivated toxins to stimulate an immune response.

Question 12

Which of the following is a major concern regarding vaccine safety that has led to public controversy?

Accepted Answer

Adverse reactions, such as allergic responses, can occur in rare cases.

Question 13

Which of the following is a characteristic of nucleic acid vaccines?

Accepted Answer

They use DNA or RNA to instruct cells to produce antigenic proteins.

Question 14

In an indirect ELISA, which of the following is detected?

Accepted Answer

Antibody in the sample.

Question 15

Which of the following is true regarding the primary and secondary immune responses to vaccination?

Accepted Answer

The secondary response is faster and stronger due to memory cells.

Question 16

Which of the following best describes hemagglutination?

Accepted Answer

Agglutination of red blood cells by antibodies or viruses.

Question 17

Which of the following is a favorable attribute of subunit vaccines?

Accepted Answer

They are less likely to cause adverse reactions than whole-cell vaccines.

Question 18

Which of the following is a real-world application of monoclonal antibodies?

Accepted Answer

Treatment of certain cancers by targeting specific cell surface markers.

Question 19

Which of the following best describes a neutralization reaction in immunology?

Accepted Answer

Antibodies bind to toxins or viruses, preventing their interaction with host cells.

Question 20

Which of the following is a key step in running a direct ELISA?

Accepted Answer

The antigen is immobilized on the plate and detected with an enzyme-linked antibody.

Chapter 18: Practical Applications of Immunology – Vaccines and Immunological Diagnostics

Study Guide - Practice Questions