May Books 7) Parasite, by "Mira Grant"
Another Hugo nomination for the eminently successful Seanan McGuire, no longer in the zombie mode but now portraying a near future California where everyone's life has been transformed by ingesting bio-engineered tapeworms. The presentation is rather similar to her zombie trilogy, each chapter being prefaced by material supposedly from other sources and the first-person narration almost identical in tone, but I felt the setting was a significant improvement - I don't really get the zombie thing anyway, so the only way was up.
Significant marks off, however, for 1) the remarkable coincidence that the protagonist and her boyfriend just happen to have parents who are significantly involved in the central scientific problem and 2) the shock twist at the end that any sensible reader will have worked out by roughly the third chapter, yet the narrator has not seen it coming at all. secretcrush has written it up in more detail including massive spoiler.