APHA Immunization Pharmacology & Vaccine Science 2

Question 1

Which immune cells are the primary producers of antibodies following vaccination?

Accepted Answer

Plasma B cells

Answer

CD8+ cytotoxic T cells

Answer

Natural killer (NK) cells

Answer

Macrophages

Question 2

What is seroconversion in the context of immunization?

Accepted Answer

Development of detectable antibodies following vaccination or infection

Answer

Conversion from live attenuated to inactivated vaccine formulation

Answer

A patient changing from one vaccine brand to a competing brand

Answer

Loss of immunity due to waning antibody titers

Question 3

Why are live attenuated vaccines generally contraindicated in severely immunocompromised patients?

Accepted Answer

The attenuated pathogen can replicate and cause disease in the absence of normal immune defenses

Answer

They contain higher antigen loads that overwhelm a weakened immune system

Answer

They require intact innate immunity to stimulate the adaptive response

Answer

The adjuvants in live vaccines are toxic to immunocompromised individuals

Question 4

Which vaccine component is responsible for a local injection site reaction such as redness and swelling?

Accepted Answer

Adjuvants like aluminum salts that stimulate local innate immune activation

Answer

Preservatives like thimerosal that cause tissue irritation

Answer

The antigen protein, which directly damages muscle fibers

Answer

Stabilizers like gelatin that cause allergic inflammation

Question 5

What is the significance of herd immunity threshold in community vaccination programs?

Accepted Answer

It is the vaccination coverage level at which pathogen spread is interrupted, protecting unvaccinated individuals

Answer

It is the minimum antibody titer needed for individual protection

Answer

It defines the maximum number of adverse events acceptable per 100,000 doses

Answer

It is the point at which natural infection provides the same protection as vaccination

Question 6

Which type of vaccine is most appropriate for a patient who is 8 weeks pregnant and needs protection against influenza?

Accepted Answer

Inactivated influenza vaccine (IIV)

Answer

Live attenuated influenza vaccine (LAIV)

Answer

Recombinant influenza vaccine (RIV) is the only option

Answer

No influenza vaccine should be given during pregnancy