THE PLAGUE.
BY JAMES C. WILSON, M.D.
DEFINITION.—An acute specific fever of short duration and very fatal, endemic in certain Oriental countries, and frequently epidemic; it is characterized by buboes, carbuncles, and petechiæ.
SYNONYMS.—([Greek: plêgê], plaga, a stroke); the Pest; Pestilence; the Bubonic, Glandular, Inguinal Plague; the Oriental, Levantine, Levant Plague; the Indian, Pali Plague; Máhámari; Septic or Glandular Pestilence; Pestilential Fever, Adeno-nervous Fever; Typhus Pestilentialis, Gravissimus, Bubonicus, Anthracicus, etc. Gr. [Greek: ho loimos]; Lat. Pestis; Fr. La Peste; Ger. die Pest, Beulenpest.
CLASSIFICATION.—The plague, pest, pestilence, and their equivalents in various tongues, are terms that have been used from the earliest historical times to designate every epidemic disease attended by great mortality. As knowledge of diseases becomes clearer the terms by which they are designated become more definite; those which did service for a class are restricted to particular groups, and new names are found for other maladies only allied to such groups by superficial resemblances. Hence by degrees the term plague has become more restricted in its use. To-day it is understood as designating exclusively the specific affection defined above, the bubo plague.
The student of medical history meets with insurmountable difficulties in attempting to classify the recorded epidemics which have been described under this term. Even when used in its more restricted signification, difficulties as to the propriety of its application to certain epidemics arise. Thus, nosologists are not in agreement as to whether the great plague—the black death—which swept over Europe in the fourteenth century and destroyed in three years twenty-five millions of inhabitants, was a modification of the bubo plague or an essentially different disease. A like difference of opinion exists in regard to the relationship between the Indian or Pali plague which has from time to time prevailed in North-western India during the present century and the true plague.
The black death of the fourteenth century and the Pali plague, though presenting many of the characteristics of bubo plague, differ from it, while they resemble each other, in one important particular. Among the earlier and more common symptoms of note are those dependent upon gangrenous inflammation of the lungs, a lesion, according to Hirsch,1 extremely rare in bubo plague. This author informs us that recent observations have fully confirmed the early opinion that the Pali plague differs from that of the Levant chiefly in this modification, and cites Pearson and Francis as saying of the former disease that "the collective symptoms are more like those of plague than of any other known disease.... We believe it to be in all essential particulars identical with the plague of Egypt."