As soon as the virus attacks, 30% of the infected will need artificial breathing support. These are called ventilators.
Of course if things are so bad people will need lots of ventilators which will be in short supply. And news shows that in this infection one has to be kept in ventilator for weeks or months before he dies or recovers.
A DIY do it yourself ventilator project in comment. He designed it keeping this scenario in mind some 10 years back.
With mech background, and lot of microcontroller work, I would have been in a good place to build some, but recently feel so tired. Like, "let it be."
Death without ventilators won't be instant but painful over long night. But again death is painful even for those that look peaceful on the outside.
Link for the interested.
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Update, 30 minutes later :
I was wondering how one would control pressure, flow, frequency and Oxygen supply accurately with this system. You can't. So this one is useless.
Plus you would need a cylinder of oxygen *every day*. Supply of which won't be there.
For anyone infected --- pray to God, and brace whatever He decides.