The spread of Omicron will lead to a second straight year of subdued celebrations in many places. The C.D.C. loosened isolation protocols for Americans who test positive.
As the Omicron variant surges, and experts say that vaccinations strongly protect against severe illness, U.S. public health officials are closely examining ways to reach the least-vaccinated areas.
The C.D.C. decision to cut the confinement period was welcomed by many business representatives, but a union leader warned that workers may feel pressure to return to their jobs too soon.
A shorter isolation period could help people return to work more quickly, but some owners also worry about how to determine when someone is healthy enough to come back.