U.S. CDC backs previous advice for 5-day isolation; no test needed

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. On Tuesday, the CDC added an explanation on its website, saying that a review of 113 studies from 17 countries showed that most transmission occurs early in the course of infection. It said the average period of infectiousness and risk of transmission was 'between 2-3 days before and 8 days after symptom onset.'