"The bacterium Borrelia burgdorferi (Bb for short) is a tiny, pale spiral, invisible to the naked eye, yet no one could invent a life so ingenious, or one so tied to so many creatures' fates. Arno Karlen takes readers on a journey through Bb's world - its ancestry and evolution, its day-to-day life, its perilous travels through ticks, mice, and deer, and, finally, its collision with humanity. Its life evokes the vast ecological web in which we and Bb are threads."--BOOK JACKET.