These three books take very different approaches to the history of infectious disease and medical science. Perhaps most ambitious, and very different, is Medical London, which aims to cover 'two thousand years of life and death in London'. The sturdy case binder holds a treasure-trove of information presented in a variety of formats. The pack comprises a hardback book, Anatomy of the City: A Guide to Medical London, complemented by six separate walk booklets which each include a map, and a softback collection of essays under the umbrella Sick City.

Anatomy of a City lists a huge range of key medical history locations, arranged by geographical region and within each region alphabetically. These include museums and other collections open to the public and full details of what they have to offer, plus opening hours and contact details, alongside 'Vanished London' sites which are significant but no longer visible. Every aspect of medical history and public health from 55 BC to 2000 AD that you can possibly think of is covered. The titles of the 6 walks give a flavour of the amazing breadth of topics: (1) Life and death by water: a walk along the medieval Thames; (2) In the footsteps of Daniel Defoe: a journey through the 'Plague Year'; (3) Gallows, ghosts and golden boys: a day in the life of an 18c medical student; (4) Tall ships and tropical diseases: medicine and the British Empire in Greenwich; (5) Pox and pleasure: Soho by night; (6) From homeopaths to psychopaths: Bohemian medicine in Chelsea.

The last-named takes in 15 sights, including the Chelsea Physic Garden, the Science Museum and Chelsea Embankment, through three hospitals to the site of Thomas Crapper's water-closet manufactory. Even if you don't take to the streets and follow the clearly laid out maps, it is fascinating reading about the medical association of each sight in the accompanying notes. There is no space here to comment on the essays, save to say that the comprehensive scheme is continued under six subject headings: City of Multitudes, City of Money, City of Madness, City of Pleasure, The bowels of the City and City of the World. The authors of this monumental study are both professional medical historians who have written and/or lectured widely; they have an engaging style and are to be congratulated on a cracking read. Who could fail to find something of interest on dipping into this beautifully produced and clearly laid out work? An added bonus is, because it has been sponsored by The Wellcome Collection, the price is only a bargain £15.99.

Dorothy Crawford's book Deadly Companions, subtitled 'how microbes shaped our history', can be read like a novel, but of course, this story is true! It begins with SARS in the 21st century, itself a medical detective tale, and then the author goes back to describe the origins of microbial life 4 million years ago and explore the links between the emergence of microbes with the cultural development of humans. The impact of various 'plagues' in our history that have affected not only the populations of people but animals and plants as well are covered in depth, but the important role of microbes in maintaining the ecosystems of our planet also receives due credit and it is made clear that the majority of these tiny life forms co-exist with us quite harmlessly (despite the title of the book!). Our behaviour has also altered theirs and as all microbiologists know, no matter what the human race does, microbes are always a step ahead and will be around long after we are extinct. A side story is the history of microbiology and the work done and in progress to combat the negative effects of microbes, as well as exploit their potential. The descriptions of the immune response to disease and how vaccination works are particularly clear, but I did wonder why it was necessary to include the R_o values of pathogens when covering epidemiology in a popular science book.

In fact, while I thoroughly enjoyed reading Deadly Companions and Medical London, I am not quite sure who they are aimed at. They are probably a bit intimidating to the general reader, but definitely not textbooks either. Deadly Companions also suffers from a paucity of illustrations and has no photographs at all, which is a shame. Both works deserve a wide readership.

Sandra Hempel, on the other hand, author of The Medical Detective, is a journalist, and her book on John Snow, cholera and the mystery of the Broad Street pump is definitely aimed at the popular market. Nevertheless, it is well-researched, as well as very readable. She describes the disease and the causative organism of cholera, and charts the course of the infection once it had emerged from India in 1817 to cause death and illness around the world in a series of epidemics. One of these hit Newcastle-upon-Tyne in 1831, where the young John Snow, a labourer's son, was apprenticed to a local surgeon. Hempel sets out the contemporary treatment for cholera, and puts the (unpopular) control measures imposed by local and national government into their political context. The story then moves on with Snow to his further training as a doctor in London and his success as a pioneer of anaesthesia. In 1853 he gave chloroform to Queen Victoria in her eighth confinement. Meanwhile, in 1848, cholera had once again appeared in London and Snow, who, after his early experiences in Newcastle had often pondered about the transmission of the disease, began to consider it in earnest. The rest of the story is familiar, but Hempel puts it in a broader context of the social conditions of the time and the attitudes of the medical establishment in this era before the germ theory of disease was proved. Snow died in 1858, but Vibrio cholerae did not and the story of cholera to the present day is recounted in the book.

Janet Hurst, SGM