About these 150,000 survivors in the Scottish Highlands...
Did these people survive simply because it's so remote in the Highlands, that the virus was never carried there? I find that slightly unbelievable because cities like Aberdeen and Inverness serve as hubs to the north east of Scotland and the Highlands respectively. Carriers would take the plague with them all over the place. Does this mean that these people were never exposed to it? That would mean they'd die as soon as they came into contact with anybody from the lowlands of Scotland or England. Look what happened to those religious types in Gone To The Angels - they were isolated, but as soon as they met survivors they contracted the plague from them and died soon after.
Going by the logic in this episode, hundreds of millions could've survived elsewhere in the world.
Opinions?