Page:Tropical Diseases.djvu/434



THE term " heat-stroke " conveys the suggestion that heat is the leading etiological factor in the various morbid conditions which custom has grouped under this and similar names.

Until irrefutable evidence has clearly demonstrated the true cause of any given disease, it is a very grave error to base the name of such disease on some -crude hypothetical etiological conception. Such a nomenclature is sure to lead to confusion, to mistakes in practice, and to retard progress. There is no better illustration of the truth of this remark than that supplied by the group of diseases under consideration. The expression "heat-stroke" covers several distinct, one might say of two of them almost opposite, clinical conditions. One of these is heat-exhaustion, virtually a syncope, which may occur anywhere and in any climate, high atmospheric temperature, whether natural or artificial, being its essential etiological factor. The other, of which hyperpyrexia is the most striking clinical feature, is a well-defined and possibly specific fever, having a peculiar endemicity and assuming at times in the endemic area almost epidemic characters. Like yellow fever, dengue, tropical elephantiasis, and other tropical diseases, this second form of heat-stroke occurs only in conditions of high atmospheric temperature; but, as with these diseases, it by no means follows that, though occurring in high temperature, it is caused by high temperature. To obviate confusion, and following the example of Sambon, I shall describe this disease under its ancient name siriasis. Besides these two well-defined morbid states associated with high atmospheric temperatures there is another but ill-defined group of heat-stroke cases