Lots of bedrest can save people if all you've got is some herbal meds.
If you don't even have that, well... RIP Your Colony
Press F to pay respects.
...Actually it didn't go quite so badly; by carefully rationing the meagre scraps of herbal medicine we did have my two most-skilled doctors were able to save all but two of my colonists- sadly, one of those was my beloved, bloodthirsty shotgun specialist, who turned out to be rather long in the tooth, biologically.
She didn't exactly
die, though. As her illness progressed she went berserk, and I had another colonist arrest her. As they left her cell/psychoid orchid, they left the doors open allowing her to escape. I know not where she went, but those pawns that knew her haven't suffered a "friend died" moodlet so I like to imagine she's still out there living on somewhere.
The other un-saveable pawn was her mother, who our chief doctor put out of her misery with a few bullets.
The doctor's a psychopath who cares not for other's opinions, anyway, so that makes her perfect for the job.
Especially if she ever botched a surgery, though I don't believe she has, to my knowledge. Even one of the affected prisoners survived! The other one I released, but he didn't make it off the map before collapsing. Conveniently, he fell right next to an existing graveyard, so we simply dug a grave beneath him as he lived his last few agonizing hours.
Actually maybe both sick prisoners died, I can't find the other one anywhere. Been a while since I played. Oh well. *shrug*