Viruses are disarmingly small and simple. None the less, the smallpox virus killed over 300 million people in the 20th century prior to its eradication in 1980. The AIDS virus, HIV, is now the single most common cause of death in Africa. In recent years, the outbreaks of several lethal virusessuch as Ebola and hanta virus have caused great public concern.In her fascinating and vividly written book, Dorothy Crawford describes all aspects of the natural history of these deadly parasites, explaining how they differ from other microorganisms. She looks at the havoc viruses have caused in the past, where they have come from, and the detective workinvolved in uncovering them. Finally, she considers whether a new virus could potentially wipe out the human race.This is an informative and highly readable book, which will be read by all those seeking a deeper understanding of these minute but remarkably efficient killers.