From Omicron to a Mars helicopter to an Alzheimer’s firestorm, our news editors choose the defining moments in science and research this year.
Coronavirus variants threatened vaccine protection
The year began — and will end — with researchers racing to learn more about variants of the SARS-CoV-2 coronavirus that are spreading across the globe. COVID-19 vaccines largely held up to variants that emerged in late 2020 and early 2021, which would later be named Alpha, Beta and Gamma. But then came Delta. In March, this variant began to rip through India with alarming speed and ferocity, racking up deaths and hospitalizations in a country that had yet to make much progress in its vaccination campaign. From there, the highly transmissible variant spread across the world, leaving devastation and more lockdowns in its path. Data rolled in showing that, once again, vaccines generally protect people infected with Delta from experiencing the most severe consequences of COVID-19 — but that the shots were less protective against Delta than against other variants. And a case of déjà vu struck in late November: Omicron, the latest variant of concern, appeared. Early data indicate that it breaches vaccine immunity significantly, but that additional vaccine doses — booster shots — improve the situation.