COVID-19 patients are unlikely to spread infectious virus particles beyond nine days after symptoms begin, even though virus is detectable in the nose and throat and stool for much longer, according to data compiled by UK researchers from 79 studies.

Doctors expect that people with severe COVID-19 who survive weeks on a ventilator will face a well documented condition called ICU-Acquired Weakness. The condition leaves long-term intensive care unit (ICU) patients with nerve degeneration, muscle wasting, and debilitating weakness. Take note, that is happens with every ICU patient that had these treatments, so it's not a "COVID" thing and it's only for the poor souls that had severe COVID. The good news is the vaccines are really good at preventing severe COVID.