New information from the CDC tonight on exactly how COVID-19 is spread.

The agency is  reiterating that prolonged, close contact is the worst culprit, especially if people aren’t wearing masks and are closer than six feet apart.

The change to the guidance involves whether the virus can linger in the air after an infected person leaves an area.

The CDC says some reports indicate transmission like that can happen in enclosed, poorly ventilated spaces, but it’s rare.

The agency says activities that require heavy breathing, like exercising or singing, can increase the likelihood of this type of spread.