Entertaining, irreverent, but always informative profiles of some 70 pathogens, mostly bacteria and viruses, that share our planet and sometimes our bodies. Although entries are arranged in alphabetical order from adenoviruses to Zika fever, this is no standard reference work. Pulitzer Prizewinning journalist Biddle (Barons of the Sky, 1991, etc.) has fun with it, giving not just the scientific facts but treating these microscopic and submicroscopic entities like personalities: ``The enteroviruses are a large mafia of viruses that inhabit the grand palazzi along the alimentary canal. The most infamous mobster causes polio.'' Along with physical descriptions of the organisms and the afflictions they cause, he provides folklore, some philosophy, some history, and often an update on what mischief the little devils have been up to recentlyoften as recently as 1994. Trivia collectors will discover that Typhoid Mary died of pneumonia, that botulism toxin is used to remove facial wrinkles, and that it was undoubtedly a staph infection that gave Job those painful boils. Entries may be under the name of the organism (Epstein-Barr virus), a disease (yellow fever), a geographical location (``Congo-Crimean/Rift Valley/California/St. Louis''), or even something as general as ``bites.'' There are no formal cross-references, but the text leads from item to related item. Biddle says that he selected his entries on the basis of their top ranking ``in prevalence, or power, or worry factor, or even literary interest.'' (Maybe so, but Zika fever is clearly there just to round out the alphabet.) Especially noteworthy are the 54 illustrations, ranging from microscopic slides of HIV provided by the Centers for Disease Control to wartime posters warning servicemen against syphilis and gonorrhea to a Japanese woodcut depicting measles as a fierce demon. A truly delightful book that manages to impart solid information about some pretty dreadful diseases without depressing or terrifying the reader.