GrannyGravy13
I am not arguing with you growstuff but an ineffective face covering worn incorrectly is as much use as a chocolate teapot.
If you Google some respected organisations, there's quite a lot of information about face masks for Covid.
I still don't go out much, so I haven't really experienced how people wear masks. On my rare trips out, most people do seem to wear them and are wearing them properly. However, I believe you that some people don't.
Masks for Covid don't need to be as effective as those needed when treating a highly infectious bacterial condition or to stop vulnerable people being exposed to bacteria. They don't need to stop every single molecule from entering the body either.
We now know that viral load has an effect. The main purpose of masks in Covid is to stop the projection of virus-laden droplets at face height. If the droplets drop to the ground, they will very quickly become ineffective. Viruses can't reproduce without a host (unlike bacteria). So anything which reduces the projection of the droplets into an enclosed environment will be helpful. I agree with you that single layer masks without any form of filter and face shields worn on their own aren't much use, nor are ones worn on the chin!
It's all about risk. Unless we lock people up in individual cells, it's impossible to stop transmission completely. I sincerely hope we don't go back into any form of lockdown, but it seems a no-brainer to try and reduce risk wherever possible. Wearing a mask and keeping one's distance unless there are genuine reasons to do otherwise seems a responsible and sensible thing to do.