[conspire] "immunity" (COVID-19, ...) Re: Numbers racket

[Rick Moen]

Quoting Paul Zander (paulz at ieee.org):

> Maybe my previous understanding was backwards.  Maybe the question is
> "why do we tend to think that most illnesses are specific to one
> species?"

I note with concurrence Deirdre's answer.  In addition, I was just going
to say that zoonotic diseases are probably de-facto rare enough that we
need an exotic word ('zoonotic') for the concept.  Our first-level
response, when we hear about things like Mad Cow Disease, that you're OK
if you're not a cow, is generally correct (albeit not if ingesting meat 
from Mad Cow Disease-infected cattle, oddly enough).

Of course, our intuition on that is partly based on relatively limited
contact between humans and other animals, and some apparently-new
zoonotic infections have been occurring as humans barge into formerly
remote animal habitats.  So, then you get odd cases of a veterinary
ailment that crosses into a single human host, and we think, wow, at
least we're lucky enough that the pathogen has no human-to-human
infection path.  Except, once in a blue moon, _that_ firewalling fails,
and then we're in November 2019 in Wuhan, and, oops!