Plagues

Title: Plagues – Their Origin, History and Future

Author: Christopher Wills

Publisher: Flamingo, 1997 (First published 1996)

ISBN: 0-00-654869-5

Pages: 303

Every one of us is susceptible to disease once in a while and has to seek medical care or resort to long recuperation which puts us to great inconvenience. However, that phase soon passes and as the normal chores are resumed, we tend to forget about it. Basking in the successes of technology, we are oblivious to the immense damage some of the diseases have caused to mankind over the centuries. Any illness which has afflicted a large proportion of people in the society is called a plague. The author presents their origin, historical occurrences and speculates on the possible vistas which they may occupy in the future. Christopher Wills is a Professor of Biology and his research ranges from the question of human origins to the nature of human genetic variation and the mechanisms by which we resist diseases. He is the author of three books for the general reader in biology: The Wisdom of the Genes, Exons, Introns and Talking Genes and The Runaway Brain.

It may seem counter initiative to us but the fact remains true that killing of a host (the afflicted animal) is not in the best interests of a pathogen attacking it. Evolution cries for survival of an individual by better adaptation but not necessary to exterminate a host which provides it with nourishment. This explains why exceptionally virulent pathogens fail to propagate further after a nasty bout of plague. The death of the infected organism closes down the way of progress for the plague-causing entity too. More benign cousins of such pathogens then continue to live happily in symbiosis with the host. The trillions of bacteria and viruses that reside in the human body, in guts, mouth or other body part are genetically only a step away from virulent strains of similar genre. But they don’t cause any ill effects on us and we have learned to live in harmony with them. History also supports this argument. Bubonic plague, which devastated London in 1665-66 in its greatest incarnation, has not returned even though no specific countermeasure was adopted by the inhabitants. Similarly malaria receded from Northern Europe by mid 19^th century, even before science established the connection between the disease and mosquitoes.

Whenever the term ‘plague’ is mentioned, we normally think of bubonic plague that devastated a great portion of humanity in 542 and 1348 CE, which may roughly thought to be the brackets of the medieval age. The disease is analysed in great detail in the book. The bacteria Yersinia pestis is the culprit which is in fact a genetically weakened cousin of the more deadly Yersinia pseudotuberculosis which affects animals. When it affects a human, the body goes into overdrive to produce phagocytes (white blood cells) to kill off the antigens, which causes the lymph nodes (buboes) to bulge extraordinarily in size, giving the disease its name. Mortality rate is usually high if untreated and when it transforms to pneumonic plague after it colonizes the lungs. Then it gets really virulent as the bacteria gets transferred between people through air by breath. The virus is vectored through rat fleas and the epidemic was thought to be extinct until it reappeared in Surat and Beed district of Maharashtra in 1994. Even though there is controversy regarding whether it was indeed the plague, the pestilence was stemmed with massive application of antibiotics and DDT.

In an amusing anecdote – if there can be anything which is even remotely amusing in the case of a deadly disease – Wills tells the case of a housemaid in New York who spread typhoid wherever she was employed and that caused many people to die. The bacteria which cause the disease, named Salmonella typhii takes a permanent residence in the gall bladders of some of the patients. While it does not result in any outward manifestation, the bacteria grow in their bladders and spill over to the environment through natural means. The maid in this case was christened ‘Typhoid Mary’ and she was arrested and quarantined. At first she escaped and found work elsewhere under an assumed name. Sudden appearances of the disease in the inhabitants of the house revealed the presence of Mary and she was again caught and incarcerated, this time for 28 years until her death. This case presents one of the gruesome aspects of man’s social life. Even though she has not committed any crime, and was being punished for no fault of hers, she suffered isolation for decades befitting a felon.

Wills goes on to describe many other diseases too like syphilis, tuberculosis and AIDS. We read of controversies among academicians over the origin of syphilis, which some of them believe to have originated in America and was introduced in Europe and elsewhere after the voyages of Columbus, who himself introduced many European diseases like smallpox and measles on the native populations in America. This is a good case of how societies often face unexpected challenges in its complex web of interactions with other people.

Wills confuses the historical provenance of some of the references he uses in the narrative. To establish the ancientness of plague, he quotes from Bhagvat Purana of India and arbitrarily assigns the date of 1500 BCE for it. This is certainly erroneous, as the Puranas are considered to be of much later origin by historians, sometimes placed around 500 CE. Similar tracing of the disease to central Asia or Africa is also unconvincing. Whatever may be the work’s advantages, historical accuracy is not one of them.

The book presents a disproportionately large mention of India and how the country is still home to a large number of deadly diseases. The narration is definitely unflattering but should serve a clear notice to clean up the house. Though often tinged with an air of condescension, Will’s description of the pathetic health infrastructure of the country is intended to open the eyes of impartial observers.

The book is somewhat dated as it was released 16 years ago and much work has been done in some areas like AIDS prevention declared to be of grave concern by Wills. Of course it is still grave, but the projected mortality figures are way of the mark, with the advantage of hindsight. A revised edition appears to be long due. One aspect the author should concern himself about is to include a primer on diseases, its methods of spread and ways of causing havoc and the essential differences between various agents of diseases. Readers like me who are confused about the differences between a bacteria and a virus remain as puzzled as ever after completing reading of the book. The glossary given at the end really is a positive point for the work and equally commendable is the conscious effort not to dabble too much with medical terms. A lengthy treatment given near the end of the book on how the species diversity of a rain forest helps to keep pathogens at bay is simply yawn-inspiring though many of the observations were collected by the author during his own academic research.

The book is recommended.

Rating: 3 Star