https://www.vice.com/en_us/article/5dm4mb/people-are-trying-to-make-diy-ventilators-to-meet-coronavirus-demand

As countries affected by the coronavirus pandemic expect to run out of ventilators and other equipment, makers are desperately trying to fill the gap with proposals for open-source, do-it-yourself devices.

Most cases of COVID-19—the disease caused by the novel coronavirus—do not require hospitalization. But for people hospitalized with severe infections, coronavirus damages their lungs and makes it hard to breathe in and circulate the amount of oxygen that their bodies need. Ventilators, machines that provide the lungs with oxygen, are proving to be key to treating these people, who seem to comprise around 10 percent of cases.