Where the agency previously warned that the virus mostly spreads through large drops encountered at close range, it now cites "small particles, such as those in aerosols", as the most common vector. "These particles can be inhaled into the nose, mouth, airways, and lungs and cause infection".
The agency's Friday update says COVID-19 is most commonly spread through small respiratory droplets called aerosols that may hang out in the air-not just via the larger droplets directly spewed like projectiles via coughing and sneezing into other people's noses and mouths. "CDC is now updating its recommendations regarding airborne transmission of SARS-CoV-2 (the virus that causes COVID-19)", it declared. Spread from touching surfaces is not thought to be the main way the virus spreads, clarified CDC. The updated CDC page had also changed language around asymptomatic transmission, shifting from saying "some people without symptoms may be able to spread the virus" to saying "people who are infected but do not show symptoms can spread the virus to others".
"CDC is now updating its recommendations regarding airborne transmission of SARS-CoV-2". On Sept. 21, however, they said that update was released in error, and they deleted the mention of airborne transmission from the CDC website."A draft version of proposed changes to these recommendations was posted in error to the agency's official website", the site now says.
President Donald Trump has publicly challenged the CDC's findings on the virus, oftentimes refusing to wear a mask and pressing the agency to reframe its guidance on schools to favor reopening.
The sudden veering away from widely accepted scientific guidance comes after months of scandal at the CDC, revolving around various episodes in which Trump administration appointees have contorted the agency's recommendations to match political exigencies.
The posting appeared to confirm emerging research that suggests tiny particles can transport the virus some distance, especially in indoor or poorly ventilated environments.
But on Monday, the CDC suddenly retracted that new guidance, saying "that does not reflect our current state of knowledge", The Washington Post reported.
The Centers for Disease Control on Monday reversed course on a recent policy change Monday, removing a days-old statement on airborne transmission of the novel coronavirus.
And in July, 239 scientists published a letter that urged the World Health Organisation and other public health organisations to be more forthcoming about the likelihood that people could catch the virus from droplets that were floating in the air. "The evidence is accumulating", Milton wrote in an email to CNN. The guidance also stated that these particles might travel further than six feet.