I don't think I've been clear. It stops the spread via already infected people. If you are wearing a mask and are not infected the evidence is that it does little to protect you.
Agreed, I don't think I was clear enough. The masks help for sure if the infected wear them. The evidence I've read suggests it isn't protective for non infected persons. (though I'm still doubtful about that despite the science being done)
Yes, they do. The masks stop that. If you aren't infected a mask likely won't help you.
**edit. define mask...that's also going to have a huge impact!
Sorry if I'm being pedantic, but what you've written is not strictly true.
Four starting premise:
1.
Covid19 spreads 'person to person' OR 'person touching contaminated surface with hand and then placing near mouth, nose or eyes'.
2. People touch their face 200+ times a day.
3. Masks are effective at capturing droplets, which is a main transmission route of coronavirus, and some studies have estimated a roughly fivefold protection versus no barrier alone .
https://www.theguardian.com/world/2...ect-me-from-coronavirus-covid-19-myths-busted
4. The evidence says mask reduce likelihood of covid19 airborne particles from entering your mouth or nose, but not 100% guarantee .
Scenario: Let's say I'm infected but asymptomatic, so not in strict quarantine but following social distancing. When out of home, wearing mask stops me from spreading covid19 particles onto my hand, which I could then spread onto surfaces, which others would later touch eg: (eg a shopping basket, trolly or a door handle). Next person who touches surface also not wearing mask, then touches mouth/nose and could get infected.
In that instance, wearing a mask helps me not to spread covid19, and not wearing mask has acted as a 'spreading' agent, and would contribute to infecting others.
Scenario: Let's say I'm uninfected. I wear a mask outside. Unknowingly I touch a surface in a shop where covid19 was alive (eg a shopping basket, trolly or a door handle). Because I'm wearing a mask, it reminds me not to touch face with hand until I get out of shop or get home. After I leave shop or when I get home, I wash hands with soap or use 60%+ alcohol based hand sanitiser. Then take off mask and can touch my face without risk.
In that instance, the mask has acted as a 'protection' barrier, and most likely saved me from being infected.