Booster shots appear to be at least 90% effective against hospitalization for Delta and Omicron. But Omicron poses a greater challenge to vaccine protection, according to three new CDC studies.

Protection is high against severe disease, and is boosted by a third shot, per official UK stats. Protection against getting mildly ill is much lower, although a booster raises it. A new chart hows ...

With the rise of omicron came the fall of long-lasting protection from reinfection with the pandemic coronavirus SARS-CoV-2, according to a study published in Nature. Using population-wide data from ...

During the 2022 Omicron wave, Novavax's protein-based COVID shot had an estimated 50% vaccine effectiveness (VE) against symptomatic infection in fully vaccinated people and a VE of 31% in those who ...

The dominant variant of the coronavirus has proved to be not only staggeringly infectious, but an evolutionary marvel. By Carl Zimmer By November 2021, nearly two years after the coronavirus emerged ...

Research reveals a sharp decline in both the effectiveness and duration of protection from prior infection post-Omicron, underscoring the need for updated vaccines to sustain immunity Study: ...

Wearing face masks may not have lowered the risk of COVID infection after the first Omicron wave, new research has shown. But that does not mean that face masks aren't useful, regardless. The wearing ...

In a recent study posted to the medRxiv preprint* server, researchers isolate BA.2.86, a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariant, and assess its ...