Yet no droplets are involved in any of the subsequent infections. Why ditch this powerful visual cue?
Also, where did that droplet come from in the first place? Why would it be relevant to the transmission of the disease when it isn't related to the previous victims in any obvious manner?
And why does it flow uphill...? Or at all, in an environment where everything is frozen solid?
The intended interpretation for the events isn't particularly satisfactory, either dramatically, story-logically or medically. And indeed the TNG reenactment suggest a completely different pathology, more of a match with the evidence. Although other stories could be cooked up, too, even better matching what we see - say, the droplet being a dangerous (even if not malicious) alien lifeform that creeps around looking for victims.
Timo Saloniemi