Although this interesting malady, now about to be considered in detail, has from very early times excited the greatest medical interest, and not infrequently, general consternation in its ravages, it is within comparatively recent years that many of its peculiar characteristics, more especially by bacteriological and statistical methods, have been properly and scientifically investigated, the same in connection with recent epidemics.
The investigation of such a varied and pandemic disorder is naturally one bristling with difficulties, the chief one being to recognise exactly what to accept or reject as influenzal from the bewildering accumulation of literature on the disease. Our researches to be of practical utility must be com- prehensive as well as selective, so many ailments not necessarily described as such, being of influenzal aetiology, and others again, sues as slight pyrexia with catarrhal symptoms being erroneously described as influenza and included in the statistics of the disease. It is injudicious therefore, to be very dogmatic in our assertions as to this or that symptom or feature being pathognomic of the disease.
We shall see later how the great honour of the discovery of the influenza baccillus belongs to Pfeiffer; his results shortly afterwaeds confirmed, and the various investigations at the time being published to the Berlin Report by Von Leyden, and the exhaustive Local Government report by Parsons.
One of the best expositions of the disease is to be found in Leichtenstern's article in Nothnagel's Handbuch, and the same has been freely utilized in this composition.