Today, we are far less likely to die from infection than at any other time in history, but still we worry about epidemics, the menace of antibiotic resistance and modern ''plagues'' like Ebola.

In this timely new book, eminent bacteriologist Hugh Pennington explores why these fears remain and why they are unfounded. He reports on outright victories (such as smallpox), battles where the enemy is on its last stand (polio), surprise attacks from vegetarian bats (Ebola, SARS) and demented cows (BSE). Qualified optimism, he argues, is the message for the future but the battles will go on forever.