In the northern part of South Korea lies the Hantaan River, and during the Korean conflict in the 1950s, 3000 United Nations troops near the river became affected with fever and myalgias associated with renal disease and ecchymoses. The disorder was initially called Korean hemorrhagic fever and was later termed hemorrhagic fever with renal syndrome. Local residents with outdoor exposure, especially those who farmed, were found to be at increased risk. Fortunately, with funding from the Department of Defense, the cause was shown in the 1960s to be a filterable agent, later called Hantaan virus -- the first hantavirus.
A similar but milder syndrome was later identified in Scandinavia and traced to exposure to a rodent, the bank vole. The causative agent was the Puumala virus, named for an area in southeastern Finland. Subsequently, in the 1980s, a very curious Carleton Gadjusek, using the newly developed polymerase-chain-reaction technique for gene amplification, examined meadow voles near his home in Maryland and found a similar virus, which he named Prospect Hill virus and which is not known to cause any disease in people. Both Puumala virus and Prospect Hill virus were found to be members of the hantavirus family.
What caught the attention of the world was an explosive outbreak of adult respiratory distress syndrome in 1993 that primarily affected Native Americans in a corner of New Mexico near an area called Muerto Canyon. Those affected had fever, tachycardia, tachypnea, and elevated white-cell counts, and 70 percent of persons with the disease died very rapidly. Outdoor exposure and exposure to deer mice were strong risk factors. Serum samples that were screened contained evidence of hantavirus infection, and genetic-fingerprint analysis, surprisingly, showed similarities between the infectious agent and Prospect Hill virus. Originally called hantavirus pulmonary syndrome, the disorder was caused by a newly recognized hantavirus, now called Sin Nombre (meaning "without a name"). This was the first demonstration of a hantavirus that caused pulmonary and not renal signs.
In their clearly written book, Of Mice, Men, and Microbes: Hantavirus, Harper and Meyer examine the history of the identification of hantaviruses and describe the pathogenesis of the illnesses they cause and their worldwide influence. It is perhaps the ecologic relations of the viruses -- in particular, between El Nino and the unusual growth of pinon nuts, food of rodents, leading to a rodent "bloom" -- that are most interesting and provocative. Readers will finish the book realizing that no infections are new; it is only our recognition of the causes that is new. Readers will also realize that disease and epidemics follow chance encounters among men, mice, and associated microbes. Despite their focus on hantaviruses, the authors take readers on a journey to understand the origin and biology of viruses, the coevolution of viruses and their hosts, and humans' fear of new outbreaks and their eventual conquest with new knowledge.
The shortcoming of this book, which is an "easy read," is that its target audience is a general one. Internists, and certainly specialists in infectious diseases, will find it slow moving. For example, petechiae are defined as "skin hem orrhages... the markers of hemorrhagic fever"; platelets are defined as "the specialized cell fragments that control blood clotting," the numbers of which decrease during infection "as they react to the damage, trying to stem the leaks that will develop unless they can contain it." In general, the language is at a level appropriate to college students, and at times readers may wish for a fast-forward button. There are more basic details and more words used to explain them than most physicians need. In addition, although the book is accurate, it has no references and will thus not appeal to scholars.
The language and tone of the book also vary. At times the tone is lyrical: the Four Corners region of the United States "is a place where change is marked in natural rhythms rather than on any human calendar, and sometimes only the broadest cycles -- the eons, the epochs -- are visible to the casual observer"; at times it is enigmatic: "if a million monkeys with a million typewriters can write Hamlet, then a billion viruses with a billion of the random changes called mutations can write influenza, Ebola, or nothing at all"; and sometimes the language is turgid, as noted above.
Despite its shortcomings, anyone interested in hantaviruses will find that this book tells a very complete story. The host, agent, vector, geography, climate, psychology, and cultural responses of the people who are infected are all described. There is much to learn.
Reviewed by Richard Wenzel, M.D.
Copyright © 2000 Massachusetts Medical Society. All rights reserved. The New England Journal of Medicine is a registered trademark of the MMS.
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