The C.D.C. has halved its recommended isolation time for asymptomatic infections to five days from 10, a move that raised criticism (and inspired memes), but Dr. Fauci said the agency may revise its guidelines yet again.
And the Biden administration is signaling that it may change the definition of “fully vaccinated” to require booster shots, a prospect that could affect what 140 million Americans can and can’t do in public.
That leaves companies with a lot to consider. Some, like Goldman Sachs, are changing their vaccination policies. The Wall Street bank will require a booster shot for all employees and visitors entering its offices beginning Feb. 1.
Employers will also need to rethink their policies if they want to bring infected workers back to the office more quickly. This makes testing the next big issue, with the Biden administration scrambling to increase supply amid shortages.
Some big firms have been buying tests in bulk to give to employees, but smaller companies may not have similar capacity. Deciding whom to prioritize for tests, who pays for them, and how to verify the results will bedevil many boardrooms in the coming months.