Dengue, a term of uncertain derivation, used to denote an epidemic disease popularly known in this country as the breakbone fever. It prevailed extensively in the West India islands in 1827 and 1828, and at the same time in many parts of the southern states of the Union. It was at that time described by Prof. Dickson, then a resident of Charleston, S. C, and the same author subsequently published several papers relating to it. It prevailed in Philadelphia in 1780, and was described by Dr. Rush. It is supposed to be identical with epidemics variously designated which have occurred at different periods in other parts of the world. The disease is an essential fever which has a short career, the average duration being about 36 hours. Sometimes it commences abruptly, and sometimes the development occupies several days. The usual symptoms of fever are present, namely, frequency of the pulse, increase of temperature, loss of appetite, chilly sensations, thirst, lassitude, etc. The disease, however, is characterized by excruciating pains in the head and eyes, and in the muscles of the neck, loins, and extremities; hence the name breakbone fever.

An eruption frequently occurs, but its character differs in different cases.

It resembles sometimes the eruption of scarlatina; hence the name scarlatina rheumatica has been applied to an epidemic supposed to be identical with this by Cocke and Copland. The eruption in some cases resembles that of measles, and in other cases it is like lichen or urticaria. Vesicles like those of sudamina and varicella have been observed. Erysipelas and purpura may occur, the latter being sometimes accompanied by haemorrhage from the nose, mouth, bowels, or uterus. Convalescence is apt to be tedious, and relapses are not uncommon. Rheumatism, abscesses, boils, and carbuncles are occasional sequels. This epidemic rarely occurs except in warm climates, and it prevails especially in cities and large towns. The number of persons affected is sometimes remarkable. Dr. "Wragg computed the number of cases at one time in Charleston, S. C, at 10,000, and during the epidemic seven or eight tenths of the population were affected. It attacks persons of either sex and of all ages. The epidemics have a brief duration, rarely extending beyond six or eight weeks. The causes are unknown. Prof. Dickson regarded the disease as contagious, but this view is not generally held, and it is opposed by facts which render it untenable.

Although the intensity of the fever is great, the disease is rarely if ever fatal. This is explained by its short duration, and the absence of any important complications. The treatment consists chiefly in the use of opium in some form to alleviate the pains, and in other palliative measures. The convalescence is hastened by tonic remedies, together with a restorative diet.