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.
"There is growing and clear scientific evidence for asymptomatic and aerosol spread," tweeted Dr. Leana Wen, a visiting professor at George Washington University. "We need an explanation. Is there more political interference at play?"
"CDC, the once venerable agency respected around the world... now decimated to be a walking zombie of its former self. So utterly terrible and terrifying."
—Eric Feigl-Ding, Federation of American ScientistsOn Friday, the CDC quietly posted new guidelines stating that the coronavirus can be transmitted "through respiratory droplets or small particles, such as those in aerosols, produced when an infected person coughs, sneezes, sings, talks, or breathes." The World Health Organization warned of the threat posed by aerosol spread over two months ago in the face of pressure from the scientific community.
"This is thought to be the main way the virus spreads," the CDC document read. "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."
After experts applauded the guidance as an important and appropriate step given the strong evidence of airborne coronavirus transmission, the CDC on Monday morning edited its website and deleted the reference to aerosols—a move commentators said will only serve to further undermine trust in the information coming out of America's public health agencies.
Jay Butler, the CDC's deputy director for infectious disease, told the Washington Post that the guidance was posted by mistake. The CDC website now contains a notice that reads, "A draft version of proposed changes to these recommendations was posted in error to the agency's official website."
"Unfortunately an early draft of a revision went up without any technical review," said Butler. "We are returning to the earlier version and revisiting that process. It was a failure of process at CDC."
A few days ago @CDCgov updated its guidance to reflect the growing consensus that coronavirus can spread “through respiratory droplets or small particles, such as those in aerosols”.
This morning, its now saying that was “posted in error” and has been taken down.
— Craig Spencer MD MPH (@Craig_A_Spencer) September 21, 2020
Given recent efforts by Trump appointees at the Department of Health and Human Services (HHS) to alter the CDC's work over the objections of career government scientists, the agency's retraction of guidance that experts say was in line with current evidence raised the possibility of more politically motivated manipulation by administration officials.
"The CDC just published scientifically valid information and then pulled it off their website and this is very likely a scandal," said Sen. Brian Schatz (D-Hawaii).
Eric Feigl-Ding, an epidemiologist and senior fellow at the Federation of American Scientists, accused the Trump HHS of "muzzling" the CDC.
"CDC, the once venerable agency respected around the world... now decimated to be a walking zombie of its former self," Feigl-Ding tweeted, linking to an archived version of the previous CDC guidance. "So utterly terrible and terrifying."