The CDC on Monday confirmed that the coronavirus is airborne and may be able to infect people who are more than six feet apart, especially indoors with poor ventilation.
The agency first said last month that the virus spreads mainly through “aerosols, produced when an infected person coughs, sneezes, sings, talks, or breathes.” CDC pulled that language days later, saying it had been posted in error and required further review.
The update posted Monday to the CDC website tempers that earlier warning. It acknowledges that airborne transmission is possible, but says the virus is more commonly spread when people are in close contact with someone who is infected. The agency defines close contact as within six feet of a sick person for at least 15 minutes.
The latest statement is more cautious and emphasizes that this form of transmission is less common than close contact with someone who has the virus. It says evidence of airborne transmission has occurred in indoor spaces with poor ventilation and especially when people are breathing heavily, singing or exercising.
“CDC continues to believe, based on current science, that people are more likely to become infected the longer and closer they are to a person with COVID-19,” the agency said in a statement. “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 background: The updated guidance comes just days after President Donald Trump was diagnosed with Covid-19.
Experts believe Trump could have been infectious at last Tuesday’s presidential debate against Joe Biden. The two candidates were indoors at podiums between 10 and 15 feet from each other. A number of White House officials who were at the debate have also tested positive. So far, Biden has twice tested negative but experts say he could still be at risk and should consider quarantining.
Organizers of Wednesday’s vice presidential debate have agreed to increase the distance between Vice President Mike Pence and Sen. Kamala Harris to 12 feet in light of concerns raised by Trump’s diagnosis.
What’s next: The guidance could also have a significant impact on the pandemic response going forward. Many states and cities have modeled their social-distancing recommendations on the CDC’s long-standing advice that the virus spreads within 6 feet or less.