Transfer of respiratory pathogens Viral deactivation in aerosols (ASIDE)
PROFESSOR: So, as an aside for more advanced students, let's try to fill in some mathematical details to provide a theory to support or interpret the Lin-Marr hypothesis of disinfection kinetics having to do with the concentration of solutes during drying and their effect on deactivating viruses. So, to put it in mathematical terms, if we have a certain number of viruses Nv in a droplet, then we'll postulate that d Nv dt is minus lambda v0, the deactivation rate per solute virion collision, times the volume fraction of disinfecting solutes we'll call phi d, which is time dependent, having to do with the size of the droplet, times Nv. The volume fraction of disinfecting solutes we'll write as alpha D, a constant, times phi s, which is the total volume fraction of solutes present. And that might be, for example, the fraction of solutes that are sodium chloride or some other salt that might be causing the damage to the virus, as opposed to the mucins or other...