They'd be fools to do so merely on the word of a clearly hostile outsider, and even if they believe you, the perceived risk from Ebola might still be smaller than the perceived risk from social isolation.
Luckily, they (say, a village family in rural Ghana) are equipped with essentially the same meat computer your are. They are perfectly able to perceive the fact that the neighbor is dying with blood pouring out of her body, just like tens of thousands of other people just have. They are able to perceive that the ultimate social isolation is having everyone you care about die. It's nice to see you're not one of those people who thinks that a farmer in Liberia, who deals with life and death every day as he tends to livestock or hunts, isn't somehow too dim-witted to grasp cause and effect when he has the basic facts. This is about social behavior DESPITE knowing the facts.
Unless it's what's just killed off everyone you know. Or look at places like Ferguson, MO, where culture just decided to burn down local shops in a tantrum over reality disagreeing with an instantly concocted bogus media mythology. Culture, like the culture of castigating your neighbors for daring to go get an education or acquiring a broader vocabulary - as seen in swaths of urban culture or patches of, say, Appalachia - is often destructive, the opposite of valuable. Pious political correctness, which employees poisonous moral equivalence in the name of assuaging misplaced guilt over the fact that some cultures actually work better than others, preserves and actually perpetuates that destructiveness.