What Lily says about Nemesis in Cold Days:
"A disease. A parasite. A poison... You must have seen the contagion spreading. It has been before your eyes for years. It is a kind of spiritual malady. A mental plague. An infection slowly spreading across the earth. It changes that which ought not change. It destroys a father's love for his family by twisting it into maniacal ambition. It distorts and corrupts the good intentions of agents of mortal law into violence and death. It erodes the sensible fear that keeps a weakly talented sorcerer from reaching out for more power, no matter how terrible the cost. Each of them tainted by the contagion. It destroyed them. I saw what it did to her [Aurora]. I didn't know what was happening to my friend, but I saw it changing her. Twisting her day by day. I loved Aurora like a sister. But in the end, even I could see what she had become."
What Maeve said, with the now-obvious lie about Lea's infection:
"Remember your godmother, bound in ice at Arctis Tor. That was when my mother trapped her and spread the contagion into her. Think of the creatures of Faerie Wyld who have been behaving irregularly and unpredicably. Think of the strange conduct of some of the Houses of the White Court, changing their diets after centuries of stasis. Think of the Fomor, active and aggressive again for the first time in millennia. None of these things is coincidence. It spreads, a force that will upend the world and all of us with it."
SO, the question is, how much is it Beside spreading disinformation to make the threat seem overwhelming and unstoppable, and how much of it is Jim Butcher pulling back the curtain and showing us what's been going on for all these casefiles?