An attenuated strain of a pathogen
A) has lost its virulence, but may be used to create a vaccine.
B) has changed its antigens to avoid an adaptive immune response.
C) is more virulent than the regular strains and may cause septic shock.
D) is an extracellular pathogen that will be cleared by innate immunity.

Question

Quizplus · Accepted Answer

An attenuated strain of a pathogen is a weakened form of the pathogen that has lost its virulence, but still retains its capacity to stimulate an adaptive immune response. Such attenuated strains can be used for vaccination because they provide immunity without causing the disease.

An Attenuated Strain of a Pathogen