936 DISEASED CAUSED BY FILTKABLE VIRUS 



defined than those of typhus. Fresh flea bites are sometimes hard 

 to distinguish from the typhus eruption. 



The heart is usually rapid and may become irregular. The blood 

 pressure is apt to be low and Shattuck believes that myocardial 

 weakness often occurs. Epistaxis may occur at the height of the 

 disease. Bronchitis often occurs during the later stages, and cough 

 is almost regularly present. Nervous symptoms of various kinds 

 are important accompaniments of the disease. In many cases a 

 state of lethargy resembling that of typhoid fever is present. There 

 may be twitching of the muscles during this stage of stupor. 

 Delirium occurs in severe cases. 



The leucocytes, as worked out by Sellards, 2 are rarely increased 

 in number, ranging in number from 3,000 to 15,000, the average 

 being between 5,000 and 7,000. Differential counts show ap- 

 proximately normal percentages. 



The most common complications are parotitis, suppurative otitis 

 and mastoiditis, and a peculiar gangrene of the extremities, es- 

 pecially of the feet, which is particularly associated with cases 

 occurring during the cold weather. This gangrene is characteristic 

 of the disease and is probably associated with the vascular changes 

 incident to the localization of the virus. Bronchitis is almost a 

 regular complication. Albuminuria is present, and the urine gives 

 a Diazo reaction. 



For a thorough discussion of the pathology of the disease we 

 refer the reader to Wolbach's Harvey Lecture. (Series 1920-1921, 

 New York Harvey Society.) 



Epidemiology. Hirsch 3 in his Handbook of Geographical and 

 Historical Pathology, associated typhus fever with the dark days 

 of the history of the world, war and famine. Typhus fever epidemics 

 have probably decimated populations and armies far back into the 

 history of the Middle Ages, and probably before. An epidemic of 

 what is probably typhus fever was spoken of in the Chronicles of 

 Joinville as almost destroying the Christian Armies near Salonika. 

 Great epidemics ravaged Central and Eastern Europe in the Eigh- 

 teenth Century, and the disease was prevalent in England and 

 Ireland at this time. Epidemics occurred in Northern England and 



2 Sellards, Typhus Fever, etc., In the Serbian Epidemic, Red Cross Repoit, 

 Harvard Univ. Press, 1920. 



9 Hirsch, Indenham Society Publication, London, 1888. 



