The U.S. Centers for Disease Control and Prevention (CDC) on Tuesday backed its week-old guidance for people seeking to end their COVID-19 isolation at five days, adding they could take a rapid antigen test if they want to and can access one, but is not requiring that.

The agency had been pressured by health experts to institute a test requirement after it cut in half its guidance last week for people to isolate after a COVID-19 infection to 5 days from 10. It said the move was based on science around transmission of the virus.