Personally, I'm not crazy about Matthew Costello as an author, so maybe check out the ones F. Paul wrote with other authors first. Just my opinion. Also, not to be a traitor to Dr. Wilson, but if you enjoy his work you might want to check out a trilogy of books written by Guillermo Del Toro and Chuck Hogan, starting with "The Strain", which will soon be a movie or maybe mini-series. Del Toro is, of course, the awesome director of such movies as "Blade II", "Hellboy (1 & 2"), "Pan's Labyrinth", and "Pacific Rim". Hogan wrote "Prince of Theives" which was made into the movie "The Town" with Ben Affleck. These books are excellent, can't put'em down vampire-apocalypse novels in the spirit of Dr Wilson's "Midnight Mass" and "Nightworld".
For the same theme, check out Justin Cronin's "The Passage" and sequel "The Twelve".