APHA Immunization Pharmacology & Vaccine Science 1 — Questions and Answers
Question 1: Which type of immunity is produced after vaccination with a live attenuated vaccine?
- Active immunity (Correct answer)
- Passive immunity
- Herd immunity
- Innate immunity
Correct answer: Active immunity
Live attenuated vaccines stimulate active immunity by triggering the immune system to produce its own antibodies and memory cells.
Question 2: What is the primary mechanism by which adjuvants in vaccines enhance immune response?
- They stimulate innate immune responses and promote antigen-presenting cell activation (Correct answer)
- They directly neutralize pathogens before immune response begins
- They reduce the concentration of antigen needed per dose
- They extend the shelf life of vaccine formulations
Correct answer: They stimulate innate immune responses and promote antigen-presenting cell activation
Adjuvants enhance vaccine immunogenicity by stimulating innate immunity and activating antigen-presenting cells, leading to a stronger adaptive response.
Question 3: Which of the following vaccines contains a polysaccharide conjugated to a carrier protein?
- Prevnar 20 (PCV20) (Correct answer)
- PPSV23
- MMR
- Varivax
Correct answer: Prevnar 20 (PCV20)
Prevnar 20 (PCV20) is a conjugate vaccine where polysaccharides are chemically linked to a carrier protein to enhance T-cell–dependent immune responses.
Question 4: What is the key difference between mRNA vaccines and traditional inactivated vaccines?
- mRNA vaccines instruct cells to produce a viral protein, while inactivated vaccines contain killed pathogen (Correct answer)
- mRNA vaccines require no refrigeration, while inactivated vaccines need ultra-cold storage
- mRNA vaccines integrate into the host genome, while inactivated vaccines do not
- mRNA vaccines provide lifelong immunity, while inactivated vaccines do not
Correct answer: mRNA vaccines instruct cells to produce a viral protein, while inactivated vaccines contain killed pathogen
mRNA vaccines deliver genetic instructions for cells to produce a target protein (e.g., spike protein), while inactivated vaccines use killed whole pathogens to stimulate immunity.
Question 5: A patient asks why they need a booster dose for their tetanus vaccine. What is the best pharmacological explanation?
- Antibody titers wane over time and a booster restores protective immunity (Correct answer)
- The initial vaccine was ineffective and a new formulation is needed
- Boosters replace live virus that degrades within the body
- Tetanus toxin mutates rapidly, requiring updated vaccine formulations
Correct answer: Antibody titers wane over time and a booster restores protective immunity
Antibody levels decline over years after initial immunization, so booster doses are required to re-stimulate memory B cells and restore protective antibody titers.
Question 6: Which component of the influenza vaccine is responsible for the annual reformulation?
- Hemagglutinin (HA) and neuraminidase (NA) antigens (Correct answer)
- Aluminum adjuvant concentration
- Preservative thimerosal content
- Egg-based growth medium
Correct answer: Hemagglutinin (HA) and neuraminidase (NA) antigens
The influenza vaccine is reformulated annually to match predicted circulating strains based on changes in the HA and NA surface antigens of the virus.
APHA Immunization Pharmacology & Vaccine Science 1
Which type of immunity is produced after vaccination with a live attenuated vaccine?