More Pandemic Fiction: Smonk by tom Franklin, 2006, 9780060846817. Backdated to correct year.
Franklin is more of a literary novelist I guest but this is more crime novel with some supernatural elements. I enjoyed the book.
Smonk is a short, fat, syphilitic rat bastard who cannot seem to die. in 1911 he returns to a small town to exact revenge. The town wants revenge on Smonk. Many people die in the conflict and a couple town survivors pursue Smonk.
There is hardscrabble survival. Children left on their own. Teen girl left to survive on sex work. Religious nutjob with a personal cavalry unit. Vampires.