Masks for the public in streets and parks been controversial nationally, with strong feelings on both sides. This week there is a review by Atul Gawande in New Yorker (May 13, here. I think this is open access if you click through enough subscription offers.)
I have been suspicious of classic surgical-type masks (typically blue paper), because of the large spaces they usually leave at the sides. Gawande notes these are actually specially-designed electrostatic fibers meant to try virus at high rates. (I'm not sure if that grade of paper technology is also found in non-certified blue paper masks sold to the public, though).
Gawande also quotes a preprint 8 page "evidence review" (not peer reviewed) by Howard et al. on mask value, here. Howard et al. include a multi color chart which I think is actually relatively simple data modeling. They assume that R=2.4 (transmittals per infected individual; bottom left corner), and they project transmittal rates if 0-100% of people wear masks which are 0-100% effective.
For example, if 100% of people wore masks that were 50% effective, R=1.2, and similarly if 50% of people wore masks that were 100% effective.
(This modeling and limit-modeling is not real data, but it can be helpful. For example, I don't know what Anthony Fauci weighs, yet I can also be 100% sure it is more than 110 pounds and less than 180 pounds. It would be great to know if the requirements for masks changed infection somewhere between [+20% to -20%], or alternately, somewhere between [-20% to -60%].)
Preprint Typesetting Watch
As far as I remember, a couple months ago, preprint articles at BioRxiv or MedRxiv were almost always very bare-bones affairs.
A week ago I noticed a preprint (Kai et al) that was upping the typesetting quality of the preprint game (here).
For my eye, the Howard et al. pre-print on mask efficiency pulls the preprint game another step higher, with quite elaborate typesetting. See a screen shot of Howard et al., page 1, below.
|Increasingly elaborate typesetting of un-reviewed preprints|