Health

I am far from qualified to answer that but I had a few thoughts.

Standard home CPAP masks just have vent holes because it is cheap and nothing else is required. Adding a vent tube and filter would be a very simple solution. I am sure there are off the shelf solutions. APNEA patients with infectious diseases have to be treated in hospitals.

An Italian doctor treating Covid 19 patients said that CPAP/BPAP machines were effective on Sky News. I do not know the details.

Some advanced BiPAP machines used in hospitals can be easily converted to a full invasive ventilator. I think they only work in pressure mode but they can control PEEP, flow etc.. IDK, There is only 20% survival with the best equipment. I wouldn’t want a 2nd rate solution used on me if I had a choice.

I read that ARDS is normally treated with high PEEP and flow. I think that that some COVID 19 patients have more compliant lungs. I have no idea how medical professionals are using ventilators to treat Covid patients. You would probably want to post that in a medical forum.