Three new observational studies from Scotland, Denmark, and the United States detail reduced hospitalizations and emergency department (ED) visits for Omicron COVID-19 infections relative to those caused by the Delta...
The Pfizer–BioNTech and Oxford–AstraZeneca COVID-19 vaccines are effective against the highly infectious Delta variant of SARS-CoV-2 — but their protection drops away over time, a study of infections in the United...