This question does NOT have an answer, but I so very much want to know

[Ferrets are Cool]

18. I was not aware of this

“Giving serum from newly recovered patients is a stone-age approach, but historically it has worked,” said Jeffrey P. Henderson, MD, PhD, an associate professor of medicine, infectious diseases, and of molecular microbiology at Washington University School of Medicine in St. Louis. “This is how we used to prevent and treat viral infections like measles, mumps, polio and influenza, but once vaccines were developed, the technique understandably fell out of favor and many people forgot about it. Until we have specific drugs and vaccines for COVID-19, this approach could save lives.”

So, he probably has a bank of 7 survivors strapped to beds down in his "bunker". One for each day of the week.