The CDC is now updating its recommendations, the statement said. The removed draft included two paragraphs that repeated similar but confusing statements.
One stated that the main way the virus spreads is “thought to be” through “respiratory droplets or small particles, such as those in aerosols, produced when an infected person coughs, sneezes, sings, talks, or breathes.”
But a later paragraph said that spread through “droplets and airborne particles” was only “possible.”
The current information has removed the mention of “particles” and spread from breathing.
It says spread is thought to occur “through respiratory droplets produced when an infected person coughs, sneezes, or talks.”
The World Health Organization (WHO) in July acknowledged that there was “evidence emerging” that COVID-19 could be spread through the air, although the WHO’s technical lead for infection prevention and control, Benedetta Allegranzi, said that the reports were not yet definitive.
The WHO’s statement came after scientists from 32 countries appealed in a letter to the medical community and relevant international bodies urging them “to recognize the potential for airborne spread of coronavirus disease 2019.”
Jose Jimenez, a chemist at the University of Colorado who signed the letter, told Reuters, “This is definitely not an attack on the WHO. It’s a scientific debate, but we felt we needed to go public because they were refusing to hear the evidence after many conversations with them.”
Jimenez said historically, there has been a fierce opposition in the medical profession to the notion of aerosol transmission, and the bar for proof has been set very high. A key concern has been a fear of panic.
“If people hear airborne, healthcare workers will refuse to go to the hospital,” he said at the time. Or people will buy up all the highly protective N95 respirator masks, “and there will be none left for developing countries.”
Jimenez said the WHO panel assessing the evidence on airborne transmission was not scientifically diverse, and lacked representation from experts in aerosol transmission.
Reuters contributed to this report.