The President's Vampire by Christopher Farnsworth

In this book we get to see what an outlier Nathaniel Cade really is: he's a vampire, but he's not on the Other Side (which has apparently infiltrated not only the CIA and a shady contractor, Archers/Andrew, but also Yale as well). There's a retrovirus here which remakes humans into snakeheads (lots of almost-plausible-sounding science)--it basically works like a zombie plague might--but it's getting better at making scarier snakeheads at every outbreak, which would imply human involvement and development. There's a lot of blood, a lot of guts, and a lot of backstabbing in this story--but the mystery is well done, and it does a nice job developing the relationship between Cade and his liaison to the President, Zach Barrows as well. I also enjoyed the development and hints about many popular conspiracy theories (especially the Kennedy assassination).