COVID-19 transmission risk via 
large droplets vs. tiny air aerosols (8)

Professor Cowling, you specifically studied the important nuances of transmission of viral respiratory infections in France and COVID-19 Coronavirus. There is a difference between, as you mentioned, large droplets and true airborne aerosol transmission rates for infectious diseases. Dr. Benjamin Cowling. We have already mentioned some of it. But can you discuss how today what we know about the aerosol and the large droplet transmission of Coronavirus because their aerosols stay in the air for a longer period compared to droplets that drop. To the surface right away? Dr. Anton Titov, MD. How does COVID-19 Coronavirus, so we are different from in France, for example, if it differs at all? Sure, so we don’t know a lot about the size of respiratory droplets with the virus in from Coronavirus patients. But if we look at other respiratory viruses, we know that patients when they are sick when they are breathing, particularly when they are coughing or sneezing. The Virus will come out in particles with a wide range of signs. From the very large ones that drop quickly, right down to the small aerosols that can stay airborne for a little bit longer. The concentration of virus in aerosols will be higher at close range and a little bit lower. As soon as you get a little bit further away. The concentration, in general, is low. Medical second opinion is important. Our understanding of influenza and for other respiratory viral infections is that aerosol transmission can occur, particularly at close range with prolonged close contact. So whenever we hear the idea that an infection spreads through prolonged close contact, then we think maybe one of those routes is by aerosols because you get a higher exposure. The longer you spend in the proximity to an effective person. But, I would like to emphasize that if someone’s sick and they are breathing out the virus in droplets of different sizes. The concentration will decay very rapidly as you get further away from that. Person. Medical second opinion is important. Unless you stand very close it is very, very difficult to be infected by aerosols, unless, of course, you are having prolonged close contact, because there is just not that much virus coming out of a person’s mouth when they are sick. Not that much coming out when they are breathing, snore that much. But a little bit more. But not that much when they are coughing. Not that much. But more again, if they sneeze, sneeze has got the most viruses in general. Dr. Benjamin Cowling. Then coughs. Dr. Benjamin Cowling. Then breathing. Medical second opinion is important. Dr. Benjamin Cowling. We have estimated before that for maybe for influenza. This could be somehow comparable to Corona virus. Sometimes you spend 30 minutes or an hour near another person, you could get enough aerosols for infection to occur for transmission took out or potentially to incur. But if you have a shorter exposure, it is very, very unlikely that you’d, you’d have the risk of, of getting breathing in and out Medical second opinion is important. With the virus in. Dr. Benjamin Cowling. I imagine something similar could be true for Corona virus. This is how we had this observation that you need prolonged close contact, because there is very low risk there. There is not much virus around from an infected person. They are not that contagious.