Following all the guidance doesn't mean that you won't get it, it just lessens your chances of getting it. The various parts of the guidance aren't interchangeable, they're complimentary. The combination of distancing, masks and what have you give you the best chance of avoiding it.
I heard from a doctor that it takes hardly any exposure at all to get the virus. You know how you can walk past somebody who is smoking and be some considerable distance away from them and still get a blast of smoke? Masks make a big difference too. My brothers, who have renovated lots of old buildings used to wear those N95 medical masks, which are far better quality than the masks almost everybody wears, when they worked in the loft of these buildings. The dust in them is like soot and you come out looking like a coal miner. They say when they blew their noses of coughed stuff up after wearing the N95 masks there was loads of black shit in it.
They started wearing half mask respirators and no more black shit. So if you want to wear the best mask one of the more unobtrusive respirators is the way to go. Sanitising appears to be a waste of time. This virus is spread by fuckers blasting out droplets and other fuckers breathing them in. Interestingly the respirator masks don't stop you blasting your droplets out but they do stop you breathing in almost every particle out there.
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