(590 ACUTE INFECTIOUS DISEASES. 



The period of incubation for malaria is uncertain. Patients sub- 

 jected to the poison for a long time, or suffering from the disease, 

 look pale and cachectic, probably from changes in the blood, per- 

 haps partly due to fever, partly to affection of the blood-forming 

 organs. The red blood-corpuscles are less numerous ; the remains 

 of those destroyed appear as pigment in the blood and some of the 

 organs. This diminution in number is greatest at first, but goes on 

 till recovery begins ; but at the same time it is said they increase 

 in size. Kelsch says the white corpuscles decrease in number faster 

 than the red do, but in the interval increase gradually, and that at 

 the time they are least numerous the spleen is largest. 



If after the intermittent paroxysms have ceased the spleen or 

 liver remain enlarged, the patient cannot be regarded as cured. 

 Chronic enlargements of the spleen may attain an enormous size ; 

 or there may be amyloid degeneration of the spleen, the liver, or 

 the kidneys. 



Where in the treatment of malarial diseases the preparations of 

 cinchona prove ineffectual, we may try eucalyptus globulus, of 

 which we may give 3ss-3ij of the tincture, or 10-20 drops of 

 fluid extract, several times daily. Another substitute for quinine 

 is arsenic, either as pills of arsenious acid or as Fowler's solution. 

 In cases of malarial neuralgia, or where there is gastric disturbance, 

 the Fowler's solution may be used hypodermically. Faradization 

 of the splenic region is said often to diminish the size of the spleen, 

 as also the use of cold douches over that organ while the patient is 

 in a tepid bath.] 



[CHAPTER XIII. 



YELLOW FEVER. 



WITHOUT discussing the question as to when and where yellow 

 fever originated, we may say that in the United States its different 

 epidemics seem to come from the West Indies, and to start among 

 us from New Orleans ; thence its course of travel is along rivers or 

 by the seaports. 



The cause of the disease is not certainly known, but it is sup- 

 posed to be in the nature of germs. The affection is not conta- 

 gious ; i. e., a patient having it, if stripped of his clothing and dis- 

 infected, may be placed among other patients without spreading 

 the disease. So, the germs do not develop and multiply in the 



