Although this book is actually a sequel, I did not feel at all hindered by the fact that I hadn't read the first one. It pretty much jumps straight into fast-paced action, which I really liked, as well as flowing smoothly. I did feel as though the laboratory seemed to lack a lot of procedures for a pandemic, considering what it was dealing with - although it was underground, apart from that it didn't seem like much else had been set out. I was also especially shocked by Ellis' brutal and sudden death, and completely didn't see it coming - I was expecting her to be a main character throughout the story.The use of multiple characters and short chapters was used effectively - lots of points of view, and a lot of cliffhangers at the end of each chapter to keep you reading so you can find out what happened. I personally felt Colin was the most developed character, although there wasn't even much of a background story to him. That was the issue with many of the characters, a lack of depth, so when their imminent deaths arrived, it didn't seem to matter too much as I didn't feel I knew them.I do feel that Wayne Simmons created a very haunting image of how people would act if this really happened - completely and utterly selfish, just out for themselves - and it's really quite scary. Overall, I enjoyed the book, and it was just the right level of gore for me ;) I felt I would have enjoyed it more if I could have connected with some of the characters, but it was a fun read that has left me questioning how people would react to such a situation. I would hope it would be nothing like Simmons' image, but I really think he has got it spot on there.Also posted on my blog, Rinn Reads.