u8 



TROPICAL MEDICINE AND HYGIENE 



increases whilst the albumin decreases and convalescence 

 is established. 



Diagnosis. The diagnosis of an epidemic of yellow 

 fever is not difficult. If severe or fatal cases occur the 

 fever, severe headache, increasing albuminuria and jaun- 

 dice, with the occurrence in a proportion of the cases of 

 " black vomit," render the diagnosis certain. In fatal cases, 

 even when there has been no black vomit, at the autopsy, 

 the contents of the stomach and duodenum will be black 

 from effused blood. 



FIG. 35. Yellow Fever. Severe attack. 



The limitation of the disease to certain quarters, or 

 even streets of a town, and the dependence of one case 

 on preceding cases are all aids in this diagnosis. The 

 diagnosis of isolated cases is more difficult. Acute 

 yellow atrophy of the liver may closely simulate the 

 severe forms of the disease and malaria with jaundice, 

 and Weil's disease have each many points of resemblance. 



There are certain points of resemblance between yellow 

 fever and blackwater fever that have in the past Jed to 

 a confusion between the two diseases, so much so that 

 both have been considered to be manifestations of 

 malaria, and are still often mistaken for " bilious remittent 

 fever " with jaundice. 



The points of similarity are the jaundice, liability to 



