Until now, experts have said that the virus, called SARS-CoV-2, doesn’t spread through the air in that way, but rather through relatively large droplets released when people cough or sneeze. Those droplets can contaminate surfaces or objects and infect people who touch the surface and then touch their faces. Large droplets are still a means of infection, but researchers now say that tiny airborne particles may also carry infectious virus. “Currently available research supports the possibility that SARS-CoV-2 could be spread via bioaerosols generated directly by patients’ exhalation,” researchers from the U.S. National Academies of Science, Engineering and Medicine wrote in an April 1 report to the White House Office of Science and Technology Policy.
If the coronavirus is airborne, that could help explain why it is so contagious, and can spread before people have symptoms.
Wearing surgical masks can cut down on the amount of virus that infected people spread, the expert panel says, citing an unpublished study from the University of Hong Kong. The letter does not address whether wearing a mask will protect the person wearing the mask from catching the illness. How much virus a person must breathe in to get infected isn’t known.