Using the point of view of each character from different countries, each story is exciting and not like. The survivors who tell these facts can be civilians, politicians, military, social and ... With a different political context, each interpretation gives another approach to this war for survival.
Always serious in his remarks, the author allows readers to question these means to survive if an epidemic of this type would spread.
World War Z (which is currently being adapted to the cinema) is a superb novel I encourage you to read as soon as possible.