1. Hiroshi tells Alan that the viral delivery system is being designed to fight cancer - all kinds, all stages. That's certainly a worthy goal. But can we believe Hiroshi? Maybe, possibly likely, certainly not completely. In particular, is Hiroshi telling the truth when he says that the medical weapon that's supposed to destroy cancer once it's delivered was not yet inserted into the genetic missiles? Doubtful to maybe - but, if true, that suggests that it's the delivery system itself that's creating all the zombies.
2. Something - presumably the viral delivery system - is having the beneficial effect of promoting rapid healing. At least, that seems to be the case for Hiroshi.
3. Cryogenic cold seems to slow down the delivery or whatever virus. Good thing, given that all of this is taking place in the big cold outside, i.e., see last week's White Room.
4. Missing children - gone missing from the area over a number of years - are also a factor. Are they the little beings we've seen out in the arctic tundra? Maybe, probably, I guess, I don't know.
5. There may be some twin or more connection in all of this, too. The law-woman who takes in Sergio has a twin brother who looks like Daniel - and I thought I heard Daniel call Hiroshi "father". Even if that's not so, there's definitely an all-in-the-family thing going on in Helix, which is interesting.
But annoying, not very interesting, is that dream sequence or whatever it was with Julia meeting her younger self and a table full of our characters out in Montana. Those things have been done dozens of times and better.
On the other hand, good to see Alan and Sarah following through on last week's kiss and sleeping together. The two are the most real people on the series, and the only relationship - at this point - that has the power to really influence events.