Plague.—The fever rapidly rises, so that the maximum temperature of 104°F. or more may be attained on the first day of the disease. In general the type of fever is continuous with a rather marked remission about the third day, following which, the fever again goes up with the appearance of the glandular involvement (bubonic plague).
In fatal cases the temperature may shoot up just prior to death. The drawn anxious countenance, the mental state and speech as of one suffering from alcoholic intoxication, and the early cardiac involvement, with very weak and irregular pulse, give one a clue to plague even before the buboes appear. Smears and cultures from the buboes make the diagnosis.
In plague pneumonia there is nothing characteristic about the rather continuous fever which sets in suddenly and continues elevated until death, which generally occurs about the third or fourth day. The marked mental involvement, the extreme illness of the patient, with but slight physical signs of the involvement of the lungs, should make one suspect a plague pneumonia during an epidemic. The abundant, rather watery sputum, which later becomes sanguineous, gives us a diagnosis by reason of its being loaded with bipolarly stained plague bacilli. This material should be rubbed on the shaven abdomen of a guinea pig to make the diagnosis absolutely sure.
In septicaemic plague, if such be considered a distinct type, there is very little that is manifest except a fever in a profoundly ill person. The powers of resistance may be so overwhelmed that the temperature response is slight and the chart not show temperature records above 100°F. or 101°F. Blood cultures make for the diagnosis in septicaemic plague.
Typhus Fever.—While the classical temperature chart is usually described as one with a rapid rise, reaching the maximum of 103° or 104° by the second day, with a fastigium of twelve to fourteen days, followed by a critical fall, yet many cases recently observed in the Balkans show a fairly gradual onset with a fall by lysis.
A stuporous condition with, about the fifth day, a rash first appearing about abdomen and flanks, to soon become petechial, are important in diagnosis. There is a leucocytosis with marked acid staining of the granules of the polymorphonuclears.
Trypanosomiasis.—The fever of trypanosomiasis is markedly irregular and may exist in natives without preventing them from carrying on their duties as porters. The onset is on the whole insidious.
In this first stage of trypanosomiasis or trypanosome fever, when trypanosomes are found only in the glands and peripheral circulation, what may probably be considered as leading peculiarities of the fever are the great daily oscillations, a normal morning temperature being succeeded by an evening rise up to 102°F. or 104°F.
While the febrile course is usual in Europeans it is often absent in natives. With them the febrile manifestations are noted in the sleeping sickness stage.
Again a very rapid, low tension pulse is present, whether the temperature be low or high. These febrile accessions are followed by apyrexial intervals.