A Great Experiment
نویسنده
چکیده
A GREAT EXPERIMENT "It is good thus to try in imagination to give any one species an advantage over another. Probably in no single instance should we know what to do. This ought to convince us of our ignorance on the mutual relations of all organic beings: a conviction as necessary, as it is difficult to acquire."-Charles Darwin. It may be characteristic of our age that so tremendous an experiment as the infection of seventy-seven million Russians with three avirulent strains of poliomyelitis virus was undertaken as with the sweep of a hand. Perhaps only a commissar's hand could do it. But much may be due to the arrogant confidence of twentieth century man and his habitual disregard of the limitations of his knowledge. Mass use of the oral vaccine followed careful small trials which firmly established that the viruses used did not of themselves cause disease. And the result of the mass application seems to have been an outstanding success. Poliomyelitis dwindled to a fraction of the number of cases reported in the preceding years. Indeed, these trials have emboldened some experts to confidently predict the eradication of the poliomyelitis viruses. Time alone can tell whether that is feasible or even possible. Meanwhile it seems of some interest to consider certain biological phenomena that will presumably affect the final result and that characterize the undertaking as a great experiment. The prevailing view seems to be that truly comprehensive immunization of a population with the vaccine viruses, feasible because of the ease of administration and economy, may provide a degree of active immunization and refractoriness to reinfection that will eliminate all possible hosts of the epidemic virus strains. Such an undertaking can doubtless be more easily carried out in a rigidly managed society but it is, of course, quite likely that universal immunization would not be required, that a threshold would earlier be reached at which the propagation of the field strains of viruses would cease. The extent of immunization necessary for control is an important value still to be determined. A greater effect would follow if the vaccine virus strains were capable of suppressing, of successfully competing with, the field strains. Under such
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عنوان ژورنال:
- The Yale Journal of Biology and Medicine
دوره 34 شماره
صفحات -
تاریخ انتشار 1961