does anyone know of actual data on this? i've ~heard~ that multiple layers of cotton are partially effective* (obviously much less effective than the ones with filters, but better than nothing)

*preventing you from spreading the virus, not protecting you from getting the virus https://twitter.com/DocSighsALot/status/1245457689116700672

in my experience with wearing (cloth and medical-grade) masks in the us (both now and in the past), people will stay the hell away from you, so that's definitely a benefit

the only exception to this is if its fire season and you're wearing an n95, then people won't stay away from you