Following the urging of scientists and researchers, the World Health Organization (WHO) is cautiously acknowledging the potential for indoor airborne spread of COVID-19.
In an update to the guide on its site regarding suggested coronavirus practices, WHO states that—while additional studies are required to fully understand the potential impact—"aerosol transmission" can't be discounted in certain instances.
"There have been reported outbreaks of COVID-19 in some closed settings, such as restaurants, nightclubs, places of worship or places of work where people may be shouting, talking, or singing," the WHO update explains. "In these outbreaks, aerosol transmission, particularly in these indoor locations where there are crowded and inadequately ventilated spaces where infected persons spend long periods of time with others, cannot be ruled out. More studies are urgently needed to investigate such instances and assess their significance for transmission of COVID-19."
WHO also points out that certain medical procedures can cause the production of "very small droplets" that are capable of staying suspended in the air for longer amounts of time.
A lengthier scientific brief from the organization, available for download here, adds that inadequate ventilation is a core problem in these potential airborne scenarios. Additionally, WHO notes, human-to-human transmission in these environments could also be the result of fomite transmission:
Further, the close contact environments of these clusters may have facilitated transmission from a small number of cases to many other people (e.g., superspreading event), especially if hand hygiene was not performed and masks were not used when physical distancing was not maintained.
Though some disagreement on the importance of the airborne discussion is present among health officials, the consensus regarding social distancing and face masks remains steadfast.
As of July 9, the CDC was reporting 3,047,671 total confirmed coronavirus cases in the U.S.