Physics of respiratory infections: do we understand it?

The COVID-19 pandemic has demonstrated how unprepared the world has been to address the basic question: How can we minimize the risk of airborne infection transmission for any respiratory viruses in a countless number of buildings where most of the population spends a substantial fraction of the day? This question goes far beyond the current COVID-19 pandemic: every year acute respiratory illnesses, such as colds and influenza infections strike, sicken millions, kill thousands and cause economic loses of billions of dollars. Scientists have been pointing to a larger body of evidence on the significance of the airborne transmission by inhalation of virus-laden respiratory aerosols that are generated during all human respiratory activities. Aerosolization in the various parts of the respiratory tract is how they are generated, and once in the air their fate depends on their size and the forces acting on the. Therefore, flow physics plays a key role in: generation of the virus-laded particles from human respiratory activities, detection and measurements of these particles, what happens to the particles in the air - transport and removal dynamics and deposition of the particles in the respiratory tract and upon inhalation. The presentation will discuss the current state of the art of physics of respiratory infections and its application in infection risk management.