JAMA Live Highlights features comments from livestream interviews by JAMA Network Editor in Chief Howard Bauchner, MD. His discussions with experts in clinical care, public health, and health policy focus on critical issues related to the coronavirus disease 2019 (COVID-19) pandemic. Comments have been edited for clarity.
On aerosols vs droplets: So the real issue is the size of the particle—droplets being 5 to 10 microns; aerosols being anything less than 5 microns. And we believe that severe acute respiratory syndrome coronavirus 2 is droplets. However, there've been enough studies now and enough cases that demonstrated that there's probably some aerosol in there as well, that it's not just big particles. It's some small particles too. I want to make the important point with regard to this that when we in health care think about droplets vs aerosols, we think surgical mask vs N95 respirator. I just want to be clear that this does not mean we all need to walk around in N95s. And that, I think, is a really important point to make. In the July 6 letter about airborne transmission, even the World Health Organization did not ask for N95s. It asked for more ventilation, air filtration, and decreased crowding.