Biology / Unit 9 Bio 1933 short lesson, about 20 seconds
Vaccines: Mechanism of Protection
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The idea
A vaccine builds immunity by exposing the immune system to a live-attenuated, killed, or subunit form of a virus, without causing full disease.
In practice
A killed-virus vaccine cannot cause infection, while a live-attenuated one replicates poorly, both training the immune system to recognize the virus.
Where people slip
A live-attenuated vaccine carries a small risk of reverting to a disease-causing form, unlike a killed-virus vaccine.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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