A Flu Vaccine Is Needed Seasonally to Be Effective but a Polio

question 57

Multiple Choice

A flu vaccine is needed seasonally to be effective but a polio vaccine is only needed once.The best explanation of this is ________.

• A) the flu vaccine is substantially weaker than the polio vaccine
• B) exposure to flu vaccine produces no memory cells from proliferating B-lymphocytes
• C) the polio virus is substantially weaker than the flu virus
• D) the flu has several strains that change seasonally

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Definitions:

Infiltrate

The process by which water or other fluids permeate into a substance through pores or small openings, often used in the context of soil absorption or espionage.

Impermeable Unit

A geological formation or material that does not allow fluids to pass through it.

Surface Water

Water that occurs in streams, rivers, lakes, oceans, and other settings on Earth’s surface.

Groundwater

Moisture trapped below the ground in the soil or within fissures and cavities of rocks.