masks were recommended going as far back as the 1918 Flu outbreak...
what exactly are you trying to say... that the CDC said masks were useless until 2020 when COVID appeared?
Anything that can trap airborne particles except loose fitting cloth or gauze can reduce the transmission of any virus from flu to COVID to whatever else.
There's a reason why
most hospitals use
N95s during surgery along with a
face shield. after thoroughly scrubbing their hands with a special antibacterial soap. Those that don't believe in the mask in stopping the spread of a contagious disease...
Just tell your Doctor and nurse assistants
prior to surgery not to wash their hands and not to wear their N95 mask with face shield. Next, sign the documents that they're
not liable for infecting a Covidiot with any contagious diseases that you may have acquired during the surgery.
During the 1918 Influenza Pandemic...Doctors and Nurses didn't really have face masks. Instead, they wrapped their face (mouth/nose area) with gauze about 3 or 4 times.
After the Pandemic, they then realize it didn't work due to the fact they typically worked in high viral load infectious areas plus it was later discovered (not talked about today)...
- Airborne viruses have another route of entry to cause infection...our eyes.

When I was hospitalized in 2016 with a deadly infection...I woke up out of a coma in a different hospital in which every medical person that enter my room...wore medical googles, N95s
or something that you would wear for going into space, face shields plus medical gloves.
Upon exit of my room...there was special contamination disposal that they took off their face mask, medical gloves, and the hospital garment...tossed them in the special garbage with the infectious sign on it.
Googles and face shield was sent somewhere for special cleaning.
There have been some schools that require face shields plus any type of face mask wear (e.g. the not reliable cloth or handkerchief). Yet, I don't know how these schools been doing so far in this Pandemic.
wrbtrader