I and many collaborators, postdocs, and students from many disciplines have explored lung mechanics and disease pathology for over 2 decades in a pan-university effort called the UNC Virtual Lung Project. In

the last decade we have explored how viruses “traffic” in mucosal barriers, including the human respiratory tract (RT), in the presence of antibodies. Then along came the novel coronavirus SARS-CoV-2, requiring a major pivot to a pre-immunity study. Over the past 20 months we developed a computational model that incorporates: detailed anatomy and physiology of the RT, and best current knowledge about SARS-CoV-2: virion mobility in airway surface liquids (ASL), epithelial cell infectability and replication of infectious virions. The model simulates outcomes from inhaled SARS-CoV-2 depositions anywhere in the RT, likelihoods of clearance versus infection, and propagation of the viral load and infection. We focus this lecture on the model and mechanistic insights into clinical observations prior to immune protection from SARS- CoV-2 and the waves of variants. Specifically: the strong likelihood of a nasal/upper RT infection from mild inhaled exposures; only 3-5% of positive nasal tests progress to alveolar pneumonia; and, the dramatic rise in nasal/URT infection from the current dominant variants.

Greg Forest received his PhD in 1979 from the U. Arizona, advised by Dave McLaughlin and Hermann Flaschka. His early work focused on the characterization and modulational stability of N-phase wavetrain solutions of integrable nonlinear wave equations (Korteweg-deVries, sine-Gordon, and focusing nonlinear Schrodinger). While at Ohio State University from 1979–1996, he developed interests in materials science and engineering of polymers and liquid crystal polymers with colleague Steve Bechtel and several PhD students, most notably Qi Wang with ongoing collaborations until today. He was recruited to UNC Chapel Hill in 1996 to build an applied mathematics program within Mathematics. Over the last 25 years, new interests have evolved in biology and medicine, which have direct connections to the COVID-19 pandemic as explained in this colloquium.

Zoom link: Contact Dmitry Zenkov for the zoom link.