with Correct Answers
100 questions
1. Aluminum salts are commonly used in vaccines as:
A. Preservatives
B. Adjuvants
C. Stabilizers only
D. Antibiotics
Correct Answer: B. Adjuvants
Rationale: Used for decades.
2. Herd immunity cannot protect against tetanus because:
A. Tetanus is airborne
B. Tetanus is not spread person to person
C. Everyone is immune
D. The vaccine is live
Correct Answer: B. Tetanus is not spread person to person
Rationale: Spores in the environment.
3. Secondary (anamnestic) immune response is:
A. Faster and stronger due to memory cells
B. Slower and weaker
C. Identical to the primary
D. Absent in children
Correct Answer: A. Faster and stronger due to memory cells
Rationale: Basis of boosters.
4. Herd (community) immunity occurs when:
A. Only animals are vaccinated
B. Everyone is infected
C. No one is vaccinated
D. Enough people are immune that disease spread is limited, protecting those who cannot be
vaccinated
Correct Answer: D. Enough people are immune that disease spread is limited, protecting
those who cannot be vaccinated
Rationale: Protects vulnerable people.
5. Giving hepatitis B immune globulin (HBIG) to a newborn provides:
A. Natural active immunity
B. Artificial active immunity
C. Artificial passive immunity
D. Herd immunity only
Correct Answer: C. Artificial passive immunity
Rationale: Ready-made antibodies.
,6. A mother vaccinated with Tdap during pregnancy protects her newborn mainly by:
A. Passing pertussis antibodies across the placenta
B. Infecting the baby
C. Vaccinating through breast milk only
D. Reducing labor pain
Correct Answer: A. Passing pertussis antibodies across the placenta
Rationale: Passive protection.
7. Children with asplenia are at higher risk from:
A. Encapsulated bacteria such as pneumococcus, Hib and meningococcus
B. Viral warts only
C. Allergies
D. Fungal skin infections only
Correct Answer: A. Encapsulated bacteria such as pneumococcus, Hib and meningococcus
Rationale: Spleen clears encapsulated organisms.
8. Cross-placental antibody transfer is greatest:
A. In the first trimester
B. After birth only
C. Never
D. In the third trimester
Correct Answer: D. In the third trimester
Rationale: Preterm infants receive less.
9. Newborns are especially vulnerable to infections because:
A. They have too many antibodies
B. They cannot get any vaccines
C. They have adult immune memory
D. Their immune systems are immature
Correct Answer: D. Their immune systems are immature
Rationale: Rationale for early vaccines.
10. Complement proteins help immunity by:
A. Marking pathogens for destruction and lysing cells
B. Producing vaccines
C. Lowering fever
D. Carrying iron
Correct Answer: A. Marking pathogens for destruction and lysing cells
Rationale: Innate system.
11. Measles requires very high vaccination coverage (about 95%) for herd immunity because:
A. It is extremely contagious
B. It is rare
C. It only affects adults
D. The vaccine is weak
Correct Answer: A. It is extremely contagious
Rationale: High basic reproduction number.
, 12. Adaptive immunity is characterized by:
A. Immediate non-specific response
B. Skin barriers
C. Fever only
D. Specificity and memory
Correct Answer: D. Specificity and memory
Rationale: B and T cells.
13. Which cells present antigens to T cells?
A. Red blood cells
B. Platelets
C. Erythroblasts
D. Antigen-presenting cells such as dendritic cells
Correct Answer: D. Antigen-presenting cells such as dendritic cells
Rationale: Initiate adaptive response.
14. Population immunity protects which group most?
A. Infants too young and people unable to be vaccinated
B. Healthy adults only
C. Vaccinated children only
D. No one
Correct Answer: A. Infants too young and people unable to be vaccinated
Rationale: Indirect protection.
15. Seroconversion means:
A. Loss of antibodies
B. A vaccine reaction
C. Blood transfusion
D. Development of detectable antibodies after vaccination or infection
Correct Answer: D. Development of detectable antibodies after vaccination or infection
Rationale: Measures response.
16. Egg allergy and influenza vaccine: current guidance states that:
A. Egg allergy is an absolute contraindication
B. Only adults can receive flu vaccine
C. People with egg allergy of any severity can receive any age-appropriate flu vaccine
D. Egg allergy requires skipping all vaccines
Correct Answer: C. People with egg allergy of any severity can receive any age-appropriate
flu vaccine
Rationale: Extra precautions no longer required.
17. PPSV23 differs from PCV because PPSV23 is:
A. A plain polysaccharide vaccine with poor response under age 2
B. A conjugate vaccine for infants
C. Live
D. A toxoid
Correct Answer: A. A plain polysaccharide vaccine with poor response under age 2
Rationale: Used for certain high-risk children 2 years and older.