Borrelia burgdorferi is the germ that causes Lyme disease. In existence for some hundred million years, it was discovered only recently. Exploring its evolution, its daily existence, and its journey from ticks to mice to deer to humans, Karlen lucidly examines the life and world of this recently prominent germ. He also describes how it attacks the human body, and how by changing the environment, people are now much more likely to come into contact with it. Charming and thorough and smart, this book is a wonderfully written biography of your not so typical biographical subject.