The Centers for Disease Control and Prevention acknowledged Monday that people can sometimes be infected with the coronavirus through airborne transmission, especially in enclosed spaces with inadequate ventilation.
The long-awaited update to the agency web page explaining how the virus spreads represents an official acknowledgment of growing evidence that under certain conditions, people farther than six feet apart can become infected by tiny droplets and particles that float in the air for minutes and hours, and that they play a role in the pandemic.
The update follows an embarrassing incident last month when the agency removed a draft that had not gone through proper review and was posted in error. The draft’s wording included a reference to aerosols – tiny droplets that can stay in the air, potentially traveling a significant distance. Officials said the draft was removed because they feared the language could be misinterpreted as suggesting that airborne transmission is the main way the virus spreads.
That is not the case. The main drivers of viral spread are larger respiratory droplets that are emitted when someone coughs, sneezes, sings, talks, or breathes, the CDC said.
“There is evidence that under certain conditions, people with COVID-19 seem to have infected others who were more than six feet away,” the updated web page states. “These transmissions occurred within enclosed spaces that had inadequate ventilation. Sometimes the infected person was breathing heavily, for example while singing or exercising. the updated web page states.”
“Under these circumstances,” the web page says, “scientists believe that the amount of infectious smaller droplet and particles produced by the people with COVID-19 became concentrated enough to spread the virus to other people. The people who were infected were in the same space during the same time or shortly after the person with COVID-19 had left.”