World Health Organization acknowledges that coronavirus can linger in the air
239 researchers wrote an open letter to the WHO, urging officials to accept the possibility that aerosols (microscopic droplets that can float in the air, potentially for hours) were an important contributor to the spread of the virus.
In revised guidelines issued Thursday, the WHO recommended avoiding enclosed spaces with poor ventilation as well as crowded places. But it did not substantially change its position on masks, maintaining that they need to be worn only when social distancing of at least six feet is not possible.
The organization granted that it was a possibility in outbreaks such as one that sickened 53 of 61 choir members who attended a March 10 practice in Washington state. Two of the singers died.
Scientists who signed the letter said that the new guidelines did not go far enough in heeding the evidence of airborne spread.