Finally, on Friday, the CDC backtracked, getting rid of the controversial language in the guidelines, now stating they advise getting tested if you have been within 6 feet of an infected person for 15 minutes or more, even if you do not have symptoms.
The WHO's Ryan said the agency still believes the disease is primarily spread through droplets, but that in crowded closed spaces with inadequate ventilation, aerosol transmission can occur.
The update 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'.
When it updated its guidance Friday, the CDC did not offer additional guidance on how to prevent the spread of COVID-19.
The CDC did not respond to requests for information on Sunday.
Airborne virus spreads easily between people, said the guidance.
Respiratory droplets are larger and fall to the ground quickly - hence the six-foot rule that's generally considered safe for social distancing amid COVID-19.
For months, scientists and public health experts have warned of mounting evidence that the novel coronavirus is airborne, transmitted through tiny droplets called aerosols that linger in the air much longer than the larger globs that come from coughing or sneezing. But in July, under increasing pressure from researchers, the World Health Organization acknowledged that the virus could remain in the air indoors and possibly infect humans.even when exercising social distances.
The New York Times reported Thursday that the first change in policy was made by officials at the Department of Health and Human Services, not scientists at the CDC.
"These particles can be inhaled into the nose, mouth, airways, and lungs and cause infection", the updated guidance said of aerosols over the weekend.
"They changed it and did not tell anyone", he said.
Experts and lawmakers are demanding answers and warning of further political meddling at the nation's premier public health agency after the CDC on Monday abruptly removed from its website guidance published just days ago acknowledging the coronavirus is airborne and can be spread through small droplets known as aerosols.
Prather said she "was beginning to think I would never see the day".
Also on Friday, CDC updated its coronavirus testing guidance to stress that anyone who has been in contact with an infected person should be tested for coronavirus.
In a statement released Monday, the CDC said the revisions to the "How COVID-19 Spreads" page happened "without appropriate in-house technical review". They said it's crucial to make sure face coverings fit properly, so that aerosols don't escape or enter through gaps in the mask around the nose or mouth. The research is funded by national choir and organ associations whose members were unable to gather during the pandemic. Ceiling units that use ultraviolet light to kill the virus are also showing promise, they said. "The evidence is accumulating", Milton wrote in an e-mail. The post said the virus can remain suspended in the air and drift more than 6 feet, and officials emphasized the importance of indoor ventilation.