12 ASHBURN AND CRAIG. 



and spermophiles to be inoculable witli spotted fever ; Stiles and Ashburn 

 were unable to produce the disease in them. Ricketts and King have 

 conveyed the infection to monkeys and guinea pigs, and more recently 

 Ricketts appears to have produced it in the horse. 



x. PROGNOSIS. 



The prognosis, in view of the mortality, is considerably better in 

 tsutsugamushi disease than in spotted fever, and this is particularly 

 true with regard to young subjects. However, in neither disease can 

 much reliance be placed on mild symptoms during the early days of 

 sickness, for in both it too frequently happens that a patient who for 

 some days has had very moderate fever, a good appetite, no pain, and 

 has appeared only slightly or not at all sick, will take a turn for the 

 worse and in a short time be in a very dangerous condition. Later, the 

 patient may die in spite of the fair promise of the early symptoms. 

 Prognosis, therefore, should be guarded. In both diseases pregnant 

 women are liable to abort and die. Judging from the cases here re- 

 ported, we may hope that the differential leucocyte count will prove 

 valuable in estimating the prognosis in given cases of tsutsugamushi 

 disease. 



IX. PATHOLOGIC ANATOMY. 



The knowledge of the conditions found postmortem in both diseases 

 is as yet incomplete, because in the region of flood fever, as in that 

 of spotted fever, there is a sentiment against autopsies and very few of 

 them have been obtained. The only pathologic conditions recognized 

 as characteristic of tsutsugamushi disease are the ulcer at the site of 

 the bite, and the moderate lymphatic and splenic enlargement. (Edema 

 of the lungs and hypostatic congestions may be found. The kidneys 

 are swollen and congested and may show acute nephritis. 



The findings in tick fever are not greatly different from those given 

 above. The characteristic ulcer and the lymphatic enlargement are not 

 present, whereas the skin lesions are striking and may include large areas 

 of extravasation, or small patches of gangrene. Eicketts's findings of 

 lymphatic enlargement in animals dead of experimental spotted fever in- 

 dicate that more careful search might reveal such enlargement in human 

 subjects of the disease. 



XII. DIAGNOSIS. 



Tsutsugamushi disease presents points of resemblance to malaria, 

 typhoid, typhus, pneumonia, and plague; its locality and the season at 

 which the disease occurs are of course important points of differentiation. 

 Examination of the blood for malarial parasites and for the Widal 

 reaction will be of further assistance, as will the absence of most of the 

 physical signs of pneumonia and the presence of the mite bite, the lym- 



