Very useful information!  I do autopsies for a living, and I have held COVID lungs.  They weigh three times what they ought to and feel as firm as liver tissue rather than the spongy texture of lung.  Why?  Because they’re completely packed with dead tissue and blood.  COVID death is miserable, and survival with COVID can still mean that your lungs got almost this bad.  Their function could be impaired for the rest of your life.  Please get vaccinated, wear your mask, keep your distance, and we’ll all get through this with fewer people on my table or in pulmonary rehab for the rest of their lives.