Note: The Centers for Disease Control and Prevention said Monday afternoon that it erroneously posted a draft of the new guidance, days after it quietly updated its website, according to reports, CNBC says.
The original story:
The federal Centers for Disease Control and Prevention (CDC) now says the coronavirus can spread through the air when someone breathes, reflecting what scientists have been saying for months.
The CDC updated its coronavirus website on Friday, saying COVID-19 can commonly spread "through respiratory droplets or small particles, such as those in aerosols, produced when an infected person coughs, sneezes, sings, talks, or breathes."
"There is growing evidence that droplets and airborne particles can remain suspended in the air and be breathed in by others, and travel distances beyond six feet (for example, during choir practice, in restaurants, or in fitness classes). In general, indoor environments without good ventilation increase this risk," the CDC's new guidance says.
Previously, the CDC's website said the virus was thought to spread mainly person-to-person when people are in close contact, via respiratory droplets emitted when someone with the virus coughs, sneezes or talks.
The virus spreads when the particles, which can be airborne, are inhaled into the nose, mouth, airways and lungs, the CDC now says. It also maintains that people can become infected with the virus when they touch something that has the virus and then touch their mouth, nose or eyes, but notes that this isn't the main way the virus is spread.
To protect yourselves and others from the virus, the CDC's website now says that in addition wearing masks, washing your hands and staying "at least six feet away" from others, people should stay home and isolate when they're sick and "use air purifiers to help reduce airborne germs in indoor spaces."
Before, the CDC's advice was to maintain a "good social distance" of "about six feet."
Another change the CDC made was to amend language about asymptomatic transmission to say "people who are infected but do not show symptoms can spread the virus to others." Previously the CDC said, "some people without symptoms may be able to spread the virus."
WHO, despite more than 230 scientists worldwide writing a letter urging it to recognize airborne transmission, still has not updated its guidance to reflect that the virus can be spread more easily than initially thought, only noting that airborne transmission of the virus can happen during medical procedures that generate aerosols.
In a July update, WHO did say it has "been actively discussing and evaluating" whether the virus may spread in other situations, such as indoor settings with poor ventilation.
Donald Milton, a professor of environmental health at the University of Maryland and author of the letter, told CNN the CDC's updated language is a "major improvement."
"I'm very encouraged to see that the CDC is paying attention and moving with the science. The evidence is accumulating," Milton told CNN, adding that it is important for WHO to do the same.