https://www.msn.com/en-CA/health/medical/scientists-infected-volunteers-with-covid–heres-what-they-found/ar-AATu6hj?ocid=sapphireappshare

Scientists infected volunteers with COVID-19 – here’s what they found

18 out of 34 got sick with mild symptoms…  The other 16 didn’t get sick.  Some severe illness ….