Vaccines train our bodies to recognize and fend off germs before they make us sick.
Traditionally, vaccines are made using viruses that have been killed or weakened, like vaccines against the flu or measles. But growing viruses is labor-intensive and sometimes risky.
Now scientists are using newer and faster technologies to create different types of vaccines against COVID-19.
There's no chance people could get infected from the shots because they don't contain the virus itself.
The target: a spikey protein that covers the new coronavirus. That protein lets the virus invade human cells. If the body's immune system recognizes the spike and blocks it, people won't get infected.
One way is to copy a section of the virus' genetic code that instructs cells to make the spike protein. Stick that "messenger RNA" into a vaccine. The person's own cells will make the harmless protein.