376 DISEASES OF UNCERTAIN .ETIOLOGY 



Typhus fever ends by crisis, otherwise they are almost indistinguish- 

 able. 



Two varieties of the same organism are possibly the causes of both 

 diseases. 



Japanese river fever may be very similar, but one should look for 

 one or more eschars near the genitals or the axilla in this disease. 



The eruption, which begins on the face, does not become petechial. 



PROGNOSIS. 



In Montana the mortality is about go per cent, and is always high. 

 In Idaho the mortality is about 2*5 per cent., always low. 

 The outlook is good when the eruption is not general and poorly 

 defined, 



TREATMENT. 



Remove the tick by applying ammonia, turpentine, kerosene or 

 carbolized vaseline. 



Cauterize the bite with pure carbolic acid. 



Cold applications, Dover's powders, &c., for the headache. 



Cold sponging for hyperpyrexia. 



Cardiac stimulants may be necessary. 



Avoid the districts where the disease is prevalent. 



Destroy the ticks and their breeding places as far as possible. 



In Montana they practise the following measures : — 



(i) The reclamation and cultivation of arable land. 



(2) The burning over of the foot-hills. 



(3) The killing of wild animals. 



(4) Hand picking and the dipping of domestic animals in arsenical 

 dips. 



(5) Sheep grazing. 



(6) The destruction of ground squirrels by the use of carbon bisul- 

 phide pumps. 



DENGUE. 

 DEFINITION. 



An acute specific, infective, non-contagious fever of unknown 

 causation, spread by the bite of the Culex fatigans and Stegomyia 

 fasciata, characterized by two febrile paroxysms, the pulse varying 

 directly with the temperature, and a marked leucopenia. 



DISTRIBUTION. 



In tropical and sub-tropical zones where the Culex fatigans abounds. 



In Egypt, Arabia, Persia, India, Burmah, Indo-China, China, 

 North America, Spain, Peru, West Indies, West Africa, Fiji Islands, 

 Western Australia, Ceylon. 



