[trhway]

>If they didn't work then healthcare workers wouldn't be upset about the shortages.

looks like a slew of hands a bit. Public mask wearing is about any masks/face covering/etc. while healthcare workers upset about shortage of medical grade masks.

Santa Clara health department specifically discourages public from using medical grade masks to alleviate the shortage for healthcare workers.

https://www.sccgov.org/sites/covid19/Pages/learn-what-to-do....

"Face coverings should not be surgical or medical masks, which are in short supply and urgently needed by healthcare workers. Instead, face coverings such as bandanas, scarfs, or home-sewn fabric coverings should be used."

[pmorici]

Masks made from commonly available fabrics were found to have similar filtration efficiency to N95 certified masks.

[0] https://pubs.acs.org/doi/10.1021/acsnano.0c03252

[trhway]

you need to tell that to those picky Canadians (https://www.cbc.ca/news/politics/n95-masks-rejected-montreal...), healthcare workers and everybody else who wants N95.