In recent years, it seems the news has been dominated by terrorism, war, and disease. There were the well-publicized anthrax bio-terror attacks of 2001, but the West Nile virus and the SARS epidemic have been very large stories since then. And of course the international progression of HIV has been of major concern for more than a decade. Those of us interested in the issues have also read books and articles about food contamination, bacterial resistance, and the possibility that known or unknown microorganisms are the true or primary cause of many of mankind's afflictions, ranging from ulcers to heart disease.
Madeline Drexler has written an engaging summary of these and many other biological phenomena which currently threaten the lives and health of citizens of the United States, although most of the contents is applicable to people everywhere. Drexler motivates each biological threat with human-interest anecdotes as well as famous stories from biological history. This draws the reader into the more technical explanations, although the book is not written at a very high technical level. Perhaps the most impressive thing is that so much interesting and useful information is communicated in just 289 pages of main text.
The short first chapter summarizes the history of how we came to be where we are, as well as describing the threat of viruses, bacteria, and even the controversial prions implicated in Creutzfeld-Jakob disease. Drexler identifies major environmental phenomena conspiring to exacerbate the problem, such as international air travel and trade, over use of antibiotics, and even increasing longevity.
The next chapter unfolds the story of West Nile virus landing in New York. The vigilance of ordinary doctors in small hospitals and in the health department along with a veterinary pathologist at the Bronx Zoo enabled this dangerous virus to be identified. Political obstacles and turf fights slowed down the process, but eventually the correct answer was obtained. This timely human-interest story leads naturally to a discussion of insect transmission of disease. Drexler also covers the history of fighting other arboviruses much as malaria and yellow fever. Of course West Nile is expected to be very much a problem in the future for the United States.
The third chapter addresses the major problem of food-borne pathogens such as E. Coli, Listeria, and Salmonella. Although the classical ``food poisoning'' symptoms suggest relatively mild symptoms followed by recovery, the reality is that many life and health-threatening diseases can be transmitted this way. The Jack-in-the-Box E. Coli contamination was widely reported a few years ago, and numerous children died in this outbreak, but the problem is far from solved. Drexler provides a sobering analysis of the food chain and the very real prospect of future outbreaks. This chapter also covers ``mad cow disease'' and its human form, new variant Creutzfeld-Jakob disease. Regulatory and record-keeping steps are needed, but there are some things consumers can do for themselves.
Next Drexler tackles the vexing problem of antibiotic resistant bacteria. She covers the history of antibiotics starting from Penicillin. The almost immediately-observed antibiotic resistance of bacteria has continued for over 70 years. We have frightening cases in which bacteria previously resistant to all standard antibiotics are gaining resistance to antibiotics of last resort such as vancomycin. Once a staph or similar bacterium becomes immune to all of our present antibiotics we could return to the pre-antibiotic days in which a scratch could be a death sentence. The public policy issues include inadequate public funding for antibiotic research and insufficient motivation for drug company research, coupled with antibiotic overuse, The central role of hospitals in propagating antibiotic resistance is also a serious issue.
The 1918 flu pandemic killed 500,000 Americans out of 100 million. India lost 12 million, 4% of its population. Experts agree that this type of flu could recur today with similar results. Drexler covers the possibility of a flu pandemic in her usual thorough fashion. The efforts of some to obtain samples of the 1918 flu virus and obtain its DNA sequence make for a fascinating story. Good public health requires accurate and timely reporting. This was emphasized by the recent SARS outbreak, which occurred after the book was published, and in which Chinese authorities failed to report victims in a timely manner. A possible causal factor in present-day flu is the close human/animal contact present in many parts of Asia. The bottom line is that we are still vulnerable.
But what about chronic disease? Isn't it true that heart disease and various cancers account for far more deaths than the viral and bacterial disease mentioned above? Yes, but in Chapter 6 Drexler tackles the controversial theory that many of these ailments are actually caused by or triggered by infection. This theory sees to be obtaining more momentum each year, as the number of associations between chronic illnesses and infection increases. It is well-known that human papillomavirus causes cervical cancer, and that hepatitis B causes liver cancer, for example, but the recent discovery that helicobacter pylori causes ulcers came as quite a shock to medicine. Drexler describes that interesting discovery by Barry Marshall, which gave great momentum to the theory of infectious causation of chronic disease.
Looking into the almost symbiotic co-existence of human and bacteria, Drexler observes ``Our bodies contain at least ten times more bacterial cells than human ones, making us walking petri dishes.'' The incredible complexity of this situation lends itself to many theories about the interaction of multiple immune responses. The theories about autoimmune diseases, characterized by inflammation, are particularly interesting and may become very important. This chapter is probably the most speculative, but one of the most thought-provoking, as well.
Chapter 7 summarizes the bioterrorism threat. The well-known anthrax and smallpox organisms are described, along with some lesser-known agents. The possibility of attacks on our crops and livestock, ``agroterrorism,'' is not neglected. Next a short history of biowarfare is included, dating back to 1346 and including the U.S. efforts at Fort Detrick and the large USSR program. The unfortunate fact is that modern biological research is proliferating just the laboratory equipment and expertise needed for biowarfare research and production. Our best means of early detection is an effective disease surveillance system to alert public health authorities to suspicious cases. Unfortunately expenditures for public health have been inadequate in recent decades to support this requirement. We are even further from the capability of handling a large outbreak.
In her final chapter, ``Think locally, act globally,'' Drexler pulls the threads of the book together and identifies some actions that can reduce the threat of diseases of many types. Although in the U.S. increased efforts in the public health area are needed, the phenomenon of globalization has led us to the situation in which outbreaks of disease in almost any corner of the globe can fly right across the ocean and bite us in a matter of hours. Hence, global public health is something that should concern us all. The only good news is that steps taken to identify and alleviate natural outbreaks of disease may be broadly effective against many threats, even bioterrorism.
Friends from France are soon going to be using our New England house for a few days while we are on vacation. Along with the usual explanations of windows, air conditioners, garage doors, etc. what comes to my mind most immediately is to warn our guests that when their small children play in our fenced back yard they should avoid the times of day with most mosquitoes and use repellent, due to the threat of West Nile virus and Eastern Equine Encephalitis. Also, they should check the children for ticks afterwards, especially the telltale red ring characteristic of Lyme disease! So the subject of ``Secret Agents'' is more than just theoretical. This reviewer believes that almost all the topics of this book should be known to an educated reader. To get such a useful summary of so many disparate areas written so well and concisely is a wonderful contribution.