Medicine and books: Emerging Infections
Authors: Imre J P Loefler
Journal: BMJ (1998)

Ed Richard M Krause 

Academic Press, £55, pp 513 

ISBN 0 212 425930 8 

Micro-organisms find Homo a promising habitat: it is the most numerous mammal, its domesticated quadrupeds outnumber animals of similar size remaining in the wild, its avian charges and cultivars cluster in monocultures, and it also clusters in densely populated townships. Moreover, impoverished by the consequences of its reproductive behaviour, confused by religion, ideology, and politicians, and exploited by consumerism, Homo seeks solace in hazardous lifestyles. 

Micro-organisms are compelled to search for new opportunities: Homo has changed the environment, exterminated numerous species, large and small, and invaded all niches of the biosphere. Micro-organisms have benefited from the recent genetic reorganisation forced on them by Homo, which tried to eradicate many but underestimated the sophistication of the prokaryotes. 

This is the scenario for Emerging Infections, a splendid collection of essays, all of them good science and full of information, surprise, and thrill. Richard Krause, of the National Institutes of Health, sets the tone in his introduction, a tone in which dispassionate inquiry into the ecology of infectious disease and compassion with the sufferers complement each other. 

Even if there will be no “ultimate pathogen,” the 10 selected in this book represent an unimaginable burden. Myobacterium tuberculosis, Vibrio cholerae, Escherichia coli (O1 57:H7), and streptococcus A have acquired multidrug resistance. The various ways in which bacteria do this is well explained. It is remarkable that the survival strategies of micro-organisms have not been anticipated earlier. 

A chapter, heavy with mathematics, explains the analytical theory of epidemics. Another demonstrates, with Lyme disease, the triangular dynamics between host, parasite, and vector. The chapters on viral infections describe influenza, dengue, HIV, Hanta, and Ebola in a thorough yet comprehensible manner. Why the “new” intestinal parasitic protozoa should deserve a chapter among all the horses of the Apocalypse, I do not know. Also, I am not sure whether the spongiform encephalopathies belong in the same company. Malaria does, however, and an excellent essay is dedicated to it. 

It is astonishing how much we know—the DNA of plasmids, hybridisation of viruses, antigenic shift, tick behaviour, the avian origins of influenza, how a new species of mosquito travelled to America. The tools of molecular biology are powerful in producing evidence for the intimate interaction of species. It is sobering to learn that, in spite of all this, our strategies to meet emerging infections are essentially 18th and 19th century inventions: sanitation, hygiene, barriers, and immunisations. The role of the most conspicuous anti-infection tools of the 20th century, chemicals, is limited. 

How behaviour propagates an epidemic is best exemplified in the complex saga of HIV infection. Other candidates that could cause epidemics of enormous impact have not been mentioned, such as schistosomiasis and Rift Valley fever. None the less, the book is well written and well edited, and I hope that the rest of the series of Biomedical Research Reports, of which Emerging Infections is one, are of such high standard. One more tribute to the editor: his introduction is wonderfully erudite yet direct and personal. Because it connects science and art, history and self evaluation, it reads like an essay written by a humanist in Renaissance times.