Why hasn't ONI or the UNSC putting an infected life form into a cryo tube and studying them? Seems like a logical way to if it were to still almost halt cell production. This could render the Flood form almost paralyzed, but yet giving the researches plenty of time to study the Flood supercells and how they infect their hosts. Hell, you could even extract a single cell out of the host/spore since they wouldn't be able to do anything about it. Hypothetically, could you allow just [i]one[/i] Flood supercell into a fresh host's immune system, then heavily isolate and irradiate it like a modern day Cancer cell? Could potentially make some kind of vaccine or something, although I'm just rambling at this point. Granted I know thats not the easiest question to answer (if there is one) but it kinda seems like a plot drop if you ask me.