U.S. officials cut the number of days that they recommend people isolate after being infected with Covid-19 to five days from 10, reflecting recent research, new pandemic-management ideas and stress on some industries as the Omicron variant has sickened workers.

The Centers for Disease Control and Prevention said Monday that people who have been infected with Covid-19 and are asymptomatic may leave isolation after five days and should wear masks around other people for five more days.