It just now occurred to me that Ellie wouldn't have been the first time they've dissected an immune. There's an easily missed document in either the hospital, or the university, they implies they've cut open other human subjects before, with no success.
So not only are the fireflies dumb as hell, they would have doomed a little girls life to learn... what, exactly? They already gleaned a lot of info just from studying one of her blood cultures. What were they hoping to find in her brain? Seems they were just far to eager to sacrifice someone on the off chance they can glean a little more info about the virus.
And these are a bunch of ragtag terrorists who pretend they're for the greater good. What about the military industrial complex? I'm sure they're making headway into the virus itself, too, but they'd obviously keep it hush.
the more I think about this the angrier i get, someone send help