...Good editing. It's a pleasure to read without annoying mistakes. Frank is flawed but trying. The madness makes for tense reading, and the action keeps you on edge. Gripping enough to consume all three of the books back to back. Oh, and as a former microbiologist, the flu virus does have the potential for turning into a haemorrhagic disease, and an epidemic like this is entirely plausible. Just in case you wonder.