droplets

What does flat pasta that forms a shape in boiling water, the over and underdiagnosis of disease, and a scientific "misunderstanding" that may have lead to many COVID-19 deaths have in common? Well, really nothing at all, other than they were all discussed, at varying lengths, in what I read this week.
Much remains biologically uncertain about COVID-19, especially when it comes to its infectiousness. For example, how many particles must be taken to allow the virus to begin to replicate within oneself? On the other hand, the virus particle itself is subject to well-established laws of physics. So, when it comes to masks and social distancing, how can physics inform our understanding? Let's take a look.