Ever since the coronavirus pandemic started, experts have been very clear about how the pathogen spreads. People can get infected when they come in close contact with carriers or those who have the virus and breathing in their respiratory droplets. One could also get infected just by touching a contaminated surface and using the same hand to touch their mouth, nose, or eyes.
But early this week, 239 researchers issued an open letter to the World Health Organization, saying that the virus that’s causing COVID-19 can actually be transmitted through aerosols in the air. They suggested that the novel coronavirus could be airborne, and this could be a bigger threat than close contact.
“Most public health organizations, including the WHO, do not recognize airborne transmission except for aerosol-generating procedures performed in healthcare settings. Hand-washing and social distancing are appropriate, but in our view, insufficient to provide protection from virus-carrying respiratory microdroplets released into the air by infected people,” the researchers wrote in their letter.
Aerosols are different from droplets. The latter would require for one to come in close contact with an infected person who could cough, sneeze, speak and breathe out droplets that contain the virus. The former, on the other hand, is trickier. Aerosols are microscopic particles that are expelled by infected people, and these particle could remain suspended in the air, per NPR.
If this mode of transmission is really true for the coronavirus, then this would mean that many people could easily contract the virus if they come to a place that has been briefly occupied by an infected individual. When they breathe in the air that contains the aerosols, they could develop COVID-19.
However, in response to the open letter, WHO said that there is still no solid evidence to prove that the coronavirus is airborne. The organization clarified that further proof needs to be established first before confirming that the virus can spread via airborne transmission.
“There is some evidence emerging but is not definitive. The possibility of airborne transmission in public settings, especially in very specific conditions — crowded, closed, poorly ventilated settings — cannot be ruled out. However, the evidence needs to be gathered and interpreted,” WHO’s technical lead for infection control and prevention Dr. Benedetta Allegranzi said.