The Discovery of the Germ

John Waller offers an in-depth history of what he calls the “extraordinary, albeit bloodless, scientific revolution” that took place between 1880 and 1900. This was a time when medicine underwent perhaps its biggest transformation and the way we think about disease was changed forever. The story he tells reads like a thriller on more than one occasion. He fills in the background from 500 bc and explains the prevailing theories of disease over time—from poisonous miasmas to the humours of the renaissance—in an instructive and amusing manner. He charts through the millenniums the process of discovery that led to the knowledge that disease is not just related to individual qualities of each patient, that there is such a thing as a specific disease, and that one disease would not develop into another through bad luck or improper treatment.

Figure 1.

John Waller

Icon Books, £9.99, pp 198 ISBN 1 84046 373 2

Rating: ★★★★

While emphasising the merits of Robert Koch and Louis Pasteur and their teams, Waller makes it clear that the fantastic discoveries of the “big four” pathogens (those causing tuberculosis, cholera, typhoid, and rabies) did not come from nowhere but had been preceded by 2000 years of observation and investigation and by the insights and discoveries of other 19th century scientists.

These precursors included the Dutchman Anthony van Leeuwenhoek, who discovered “little animals” in white matter scraped from his teeth, the English epidemiologist John Snow, who proved that cholera is waterborne, the Austro-Hungarian doctor Ignaz Semmelweis, with his work on puerperal fever, and the surgeon Joseph Lister, who discovered the importance of handwashing procedures. The fact that the Koch and Pasteur teams were in constant competition with each other only served to push forward the march of science, and Waller's description of this competition makes the book into a real page turner.

As Waller himself says: “Only the term `revolutionary' can convey a proper sense of the magnitude of the change that medical practice has undergone.” The previous cynicism with which doctors greeted medical remedies was replaced by sound scientific knowledge. Discoveries about germs paralleled advances in public health, and their combined insights led to fundamental changes in general health and standards of living—and did so in a mere 100 years.

A useful bibliography of source material rounds off this remarkable little book. My only criticism: an index would have been useful.