INTERCURRENT DISEASES.—Many in stances of the occurrence of another in fection with typhoid fever have been recorded. It was at one time thought that malarial fever was a frequent com panion of typhoid, and the probability of a hybrid disease—typho-malarial fe ver—was strongly believed in by many physicians. It is doubtful if there is an instance in pathology of the combina tion of two diseases to form a third, and, since the discovery of the organism of malaria, the two diseases have rarely been found in the same person. There is therefore no reason for the existence of the term "typho-malarial fever," and it should be excluded from the list of dis eases. The close resemblance between some forms of the wstivo-autumal type of malarial fever bears to typhoid has partly given rise to this error. Again, cases of typhoid fever sometimes occur with an irregularity of temperature, the result often of a mixed infection which strongly reminds one of intermittent fever.
Certain specific infections have oc curred with typhoid fever; for instance, measles, erysipelas, and septimmia.
Typhoid fever may occur during the course of such chronic diseases as tuber culosis and diabetes, when its course is much less favorable than under ordinary circumstances. In the latter disease the temperature does not exceed 102° or 103°, but there is a great tendency to adynamia.
Diagnosis. — The general diagnostic characteristics are gradual onset, slow rise of temperature with daily elevations, the compressible and dicrotic pulse, ep istaxis, the tongue coated with a white fur dense in the centre and disappearing at the edges, dullness of countenance, meteorism, appearance of rose-colored spots, enlargement of the spleen, and the absence of leucoeytosis.
The early diagnosis of typhoid fever has been found difficult on account of the slow development of symptoms and of their resemblance to those of other diseases. The difficulty has been largely removed by Widal's serum-reaction.
[The fact that the blood-serum from immunized animals had the effect of causing the movements of the bacilli to cease and to collect them in clumps had been observed by several pathologists. Gruber, at the Congress for Internal Medicine, 1S96, read a paper on the ag glutinative power of blood-serum of men who had suffered from cholera and typhoid fever. Widal introduced this method for the diagnosis of typhoid fever.
The profession of this continent was first directed to this means of by Dr. Wyatt Johnson,•of Montreal, in a paper read at the Buffalo meeting of the American Public Health Association, September. '96 (N. Y. Med. Jour., Oct. 3, '96). Since that time the literature has increased to an enormous volume.