01 / The world before
Messenger RNA was difficult to use safely and effectively as a medicine.
02 / The discovery
Nucleoside modifications helped make mRNA vaccine technology practical.
03 / The people
Karikó, Weissman and larger vaccine development teams.
04 / The obstacles
Testing, manufacturing, distribution and trust required more work.
05 / The world after
A platform supported COVID-19 vaccine development.
06 / Why it still matters
The method continues to be studied for other uses.