1. The key difference between active and passive immunization is:
A. Active immunization provides immediate immunity
B. Passive immunization requires antigen exposure
C. Active immunization induces memory cell formation
D. Passive immunization lasts longer than active

C. Active immunization induces memory cell formation

2. Which of the following is an example of natural passive immunity?
A. Breast milk antibodies
B. Receiving a flu vaccine
C. Recovering from measles infection
D. Injection with antivenom

A. Breast milk antibodies

3. Passive immunization is advantageous because:
A. It provides long-term protection
B. It gives immediate protection
C. It enhances T cell memory
D. It can be administered orally only

B. It gives immediate protection

4. The term “horse α-snake” in vaccines refers to:
A. Recombinant vaccines
B. Source species of antibodies
C. Attenuated virus strain
D. Chemical adjuvant

B. Source species of antibodies

5. What is the main goal of vaccination?
A. To treat infections
B. To boost innate immunity
C. To generate long-term adaptive immune memory
D. To increase white blood cell count

C. To generate long-term adaptive immune memory

6. The difference between vaccination and immunization is:
A. Immunization always requires an injection
B. Vaccination causes passive immunity
C. Vaccination introduces antigen; immunization is the resulting protection
D. There is no difference

C. Vaccination introduces antigen; immunization is the resulting protection

7. Which disease is the only one eradicated by vaccination?
A. Measles
B. Smallpox
C. Polio
D. Tetanus

B. Smallpox

8. Live attenuated vaccines:
A. Contain dead microorganisms
B. Provide weaker immune responses
C. Can replicate in the host
D. Cannot cause infection in immunocompromised people

C. Can replicate in the host

9. Which vaccine type carries no risk of infection?
A. Live attenuated
B. Inactivated/killed
C. Recombinant vector
D. mRNA

B. Inactivated/killed

10. The oral and inactivated polio vaccines differ because:
A. Both are live
B. The oral form induces mucosal IgA immunity
C. The inactivated form is more natural
D. The oral form is injected

B. The oral form induces mucosal IgA immunity

11. What is an adjuvant?
A. A stabilizer in vaccines
B. A molecule that enhances immune response
C. A viral antigen
D. A carbohydrate subunit

B. A molecule that enhances immune response

12. Liposomes and ISCOMs are used in vaccines to:
A. Kill bacteria directly
B. Deliver antigens more effectively
C. Replace adjuvants
D. Increase shelf life

B. Deliver antigens more effectively

13. The NVICP (National Vaccine Injury Compensation Program) was created to:
A. Fund new vaccine research
B. Compensate people injured by vaccines
C. Mandate vaccinations for all citizens
D. Approve vaccine licensing

B. Compensate people injured by vaccines

14. The VAERS system is used to:
A. Record and monitor vaccine side effects
B. Create new vaccines
C. Approve vaccine safety
D. Distribute vaccines

A. Record and monitor vaccine side effects

15. Non-vaccination can lead to:
A. Herd immunity
B. Disease outbreaks
C. Higher antibody levels
D. Reduced transmission

B. Disease outbreaks

16. Therapeutic vaccines are designed to:
A. Prevent infection
B. Treat existing diseases like cancer or HIV
C. Induce allergies
D. Replace antibodies

B. Treat existing diseases like cancer or HIV

17. The spike (S) protein of SARS-CoV-2 binds to which receptor?
A. CD4
B. ACE2
C. MHC I
D. FcγR

B. ACE2

18. The relationship between infectivity and mortality generally shows:
A. Highly infectious diseases are always deadly
B. As infectivity increases, mortality often decreases
C. There is no relationship
D. High mortality always means high infectivity

B. As infectivity increases, mortality often decreases

19. How do mRNA vaccines work?
A. They deliver antibodies directly
B. They provide live viruses
C. They use host cells to make viral proteins that trigger immunity
D. They neutralize toxins

C. They use host cells to make viral proteins that trigger immunity

20. Herd immunity occurs when:
A. Everyone is infected
B. Enough people are immune that disease spread is limited
C. Immunity only exists in animals
D. Only children are vaccinated

B. Enough people are immune that disease spread is limited

21. What is the main advantage and disadvantage of passive immunization?

A. Advantage: long-lasting; Disadvantage: slow onset
B. Advantage: immediate protection; Disadvantage: no memory, short-lived
C. Advantage: stimulates memory; Disadvantage: requires multiple doses
D. Advantage: prevents viral entry; Disadvantage: causes autoimmunity

B. Advantage: immediate protection; Disadvantage: no memory, short-lived

22. Which factor contributed MOST to the eradication of smallpox?

A. Animal reservoirs that diluted the virus
B. Lack of symptoms in infected individuals
C. Human-only reservoir, visible rash, and an effective vaccine
D. Short survival of the virus outside the body

C. Human-only reservoir, visible rash, and an effective vaccine

23. What are the three main goals of vaccination?

A. Increase antibody decay, reduce immunity, create tolerance
B. Prevent disease, reduce transmission, achieve herd immunity
C. Boost inflammation, increase fever, activate macrophages
D. Eliminate all pathogens worldwide

B. Prevent disease, reduce transmission, achieve herd immunity

24. Which option correctly defines an adjuvant and gives an example?

A. A toxin that weakens vaccines; example: botulinum toxin
B. A compound that enhances immune responses; example: alum
C. A viral vector for vaccines; example: adenovirus
D. A memory cell marker; example: CD40L

B. A compound that enhances immune responses; example: alum

25. What is the difference between variolation and vaccination?

A. Variolation uses cowpox; vaccination uses smallpox
B. Variolation uses weakened virus; vaccination uses inactivated virus
C. Variolation used smallpox material; vaccination used cowpox for safer immunity
D. They are identical practices

C. Variolation used smallpox material; vaccination used cowpox for safer immunity

26. What is rational vaccine design?

A. Randomly testing antigens until immunity is generated
B. Using computational models only
C. Designing vaccines based on antigen structure, immune mechanisms, and genetics
D. Creating vaccines without considering immune response

C. Designing vaccines based on antigen structure, immune mechanisms, and genetics

27. How does SARS-CoV-2 enter host cells?

A. Using MHC I receptors
B. Spike protein binding to ACE2 receptors
C. Attaching to red blood cells
D. Binding complement proteins

B. Spike protein binding to ACE2 receptors

28. What is the purpose of a vaccine booster?

A. To suppress memory cells
B. To reduce antibody levels
C. To increase or renew memory responses and raise antibody titers
D. To replace previous vaccinations entirely

C. To increase or renew memory responses and raise antibody titers

29. What is herd immunity threshold?

A. The number of people who choose not to get vaccinated
B. The percent of a population that must be immune to stop disease spread
C. The minimum number of vaccine doses needed per person
D. The amount of viral load required for infection

B. The percent of a population that must be immune to stop disease spread

30. What is the purpose of VAERS?

A. To approve new vaccines
B. To track and investigate reports of adverse vaccine events
C. To produce vaccines for public use
D. To measure antibody titers after vaccination

B. To track and investigate reports of adverse vaccine events