The Centers for Disease Control and Prevention acknowledged today that the coronavirus can sometimes be spread through small particles that can linger in the air and infect people who are more than six feet away from an infectious person.

The agency updated its website on how Covid-19 spreads with the information and alerted reporters in a news release. The agency last month posted and then removed a guideline on airborne transmission, which it later described as a draft posted in error.

“Today’s update acknowledges the existence of some published reports showing limited, uncommon circumstances where people with Covid-19 infected others who were more than 6 feet away or shortly after the Covid-19-positive person left an area,” the agency said in the release.

The agency reiterated that it’s more common for the virus to spread through close contact with an infected person. The update today doesn’t change the CDC’s recommendations for how to protect against infection by wearing masks, staying six feet apart and washing hands.