Justinian's Flea: Plague, Empire and the Birth of Europe. William Rosen. Jonathan Cape. [pounds sterling]20.00. xi + 367 pages. ISBN 978-0-224-07369-1. This history, first published in the US, recalls the old adage about missing nails, shoes, horses, battles and victories. It is a study in the role of health in history, in particular, the pandemic that swept over Europe after the Emperor Justinian had reincorporated modern Italy, Spain and North Africa into the Roman Empire governed ...