WMDistraction

Interesting novelty account... I think I like you... for now.

The two aren't mutually exclusive.

Finally, an undeniable counterargument to anti-immigration politicians:

"Sir, excuse me for being forward, but do you hate science?"

I kind of read it like how certain cultures can "see" more colors simply because they have words for those colors. Your mind is so used to condensing information into ever-smaller units that it starts ignoring other parts of its environment. Once the mind relegates something to being unimportant, it's hard for you to ever notice that thing unless you're really looking out for it.

It's part of the reason that adult language learners (sorry, this is what I study :X) have difficulty "processing" new sounds of a different language. It's not that they can't hear the new sound, but it's that their brain ignores them completely. Adult learners who've been able to "retrain" their brain to listen for any and all sounds have also been able to learn how to pronounce the "new" sounds much better, on average.

tl;dr - If the brain doesn't need to notice it, over time, it won't.

Not a doctor, but my understanding of the disease is that there's little danger posed to developed countries. As long as people don't accidentally consume the bodily fluids of others and keep generally good hygiene, it doesn't really spread.