According to Dr John Campbell on YouTube, there is scientific evidence that wearing a mask protects the wearer to some extent. If you are exposed to someone breathing out the virus near you, the mask cuts down the number of virus particles you breathe in (reduces your viral load), so you are more likely to be able to fight off the infection. If you do get it you are likely to have milder symptoms. Heavy viral load = worse illness.
I can really recommend Dr John’s videos. He is a former A & E nurse and nurse trainer with a PhD.
Sorry if I am repeating something already said - I don’t have time to read the whole thread.
Halal and Kosher meat should labelling be mandatory?
Does anyone have a middle name?
What "back then" inconvenience would annoy today's youngsters?
