AT various periods in the history of the world there have been presented diseases of the most singular kind dependent upon imitation or moral contagion.
Such diseases have assumed an epidemic form, as convulsive affections bearing the various names of Dancing mania; Tarant St. John's. Dance; St. Vitus' Dance; Tigretier; Sympa thy; Convulsionism, or Secourism; Leaping Ague; and, In other instances the imitative disease has taken the form of paralysis, or of some other serious physical malady such as pulmonary consumption. In a third set of cases it has taken the form of suicide.
The motional type of the imitative diseases has been known from an early period in the history of medicine, but the grandest manifestations which have been recorded of it, in its various phases, broke out, in the fourteenth century, soon after the sub sidence of the great typhus plague or Black Death. The moral effects of that plague itself had been very severe. The mental shock sustained by all nations during time prevalence of the Black Plague is, says the learned historian Hecker, without parallel, and beyond description. " Many fell victims to fear, and the most stout-hearted lost their confidence. The pious closed their accounts with the world, eternity presented itself to their view, and their only remaining desire was for a participation in the consolations of religion, because to them Death was disarmed of his sting. Repentance seized the transgressor, and an awful sense of contrition seized Christians of every community." But this zeal afterwards took another turn, I may say, many turns, and in 1374 there commenced in Germany the astounding epidemic of St. John's Dance, called sometimes the dancing mania of Germany and the Netherlands. In this year, the same historian, Hecker, tells us, there appeared at Aix-la-Chapelle assemblages of men and women who had come out of Germany, and who, united by one common delusion, exhibited the following strange spectacle. " They formed circles hand in hand, and appearing to have lost all control over their senses, continued dancing, regardless of the bystanders, for hours together in wild delirium, until at length they fell to the ground in a state of exhaustion. They then complained of extreme oppression, and groaned as if in the agonies of death, until they were swathed in cloths bound tightly round their waists, upon which they again recovered, and re mained free from complaint until the next attack." The swath ing was resorted to on account of the tympany or distention of the body, which followed the spasmodic ravings; but sometimes the bystanders relieved the patients in a ruder manner, namely, by trampling on the affected parts. " While dancing, the dancers neither saw nor heard, being insensible to external impressions, but were haunted by visions. When the disease was completely developed, the attack commenced with epileptic convulsions. Those affected fell to the ground senseless, panting, laboring for breath. They foamed at the mouth, and suddenly springing up, began their dance with strange contortions." The disease, appearing at Aix-la-Chapelle in July, 1374, ex tended through the Netherlands, and through Belgium, to Co logne, where more than five hundred were attacked; and to Metz, where eleven hundred suffered.
It is supposed that as the first dancers in Aix-la-Chapelle ap peared in July, with St. John's name in their mouths, that the wild revels of St. John's day gave rise to the plague.
About forty-four years later another dancing plague, called St. Vitus's dance, broke out at Strasburg, and extended largely. The sufferers in this case were conducted to the Chapels of St. Vitus, near Zabern and Rotestein, where, by the ministrations of the priests, they were said to be cured. The minds of the suffer ers, according to Hecker, were probably soothed by the narration of a legend respecting St. Vitus, that before his death by the headsman, in the reign of Diocletian, he prayed that he might protect from the dancing mania all who should solemnize the day of his commemoration, and fast upon the eve of it, and that a voice from heaven was heard saying, "Vitus, thy prayer is accepted."