It doesn't even work with full filtration - even if you had bottled air. It just does not operate like that. If you are a certain person in a certain state you may have bout of illness with certain symptoms but the air you breathe is NOT the deciding factor, or even a factor. Everyone breathes the same air, not everyone gets/got/will get ill from something in the air... causes of illness have more to do with the person. Healthy people do not get ill - that is all there is to it. No mask will help.
It doesn't even work with full filtration - even if you had bottled air. It just does not operate like that. If you are a certain person in a certain state you may have bout of illness with certain symptoms but the air you breathe is NOT the deciding factor, or even a factor. Everyone breathes the same air, not everyone gets/got/will get ill from something in the air... causes of illness have more to do with the person. Healthy people do not get ill - that is all there is to it. No mask will help.