14 



DISEASES DUE TO PROTOZOA 



becoming more numerous towards the crisis, after which they com- 

 pletely disappear. They are not always seen during the relapse, and 

 may not be found at all during a typical attack. On the other hand, 

 they have been known to be so numerous that the circulation of the 

 blood has been hindered and a dusky lividity caused (Carter). 



Rigors are usually absent in this form. 



After the crisis, instead of feeling better, there is more often 

 collapse, sometimes resembling that in a cholera patient. There is 

 much debility. 



Relapsing fever. Indian. 



In 16 per cent, of cases there is a sudden rise of temperature during 

 the first intermission period when spirochaetes are not found in the 

 blood. 



Haemorrhage from the stomach and intestines is more common than 

 in the other forms. Parotitis is present in 10 per cent, of cases. 



Bile in the urine is scanty. 



Epistaxis occurs in from 10 per cent, to 15 per cent, of cases. 



Vomiting of bile occurs frequently, 70 per cent, to 80 per cent. 



Diarrhoea is present in 10 per cent. 



Maniacal symptoms are known. 



The first relapse occurs about the fourteenth day from the onset, 

 seventh day from the intermission. The second intermission may last 

 longer than the first ten days. Second relapses are common, but the 

 liver does not so markedly enlarge, and the crisis is not so well marked. 



A third relapse may occur after a secondary intermission of ten to 

 seventeen days. 



The percentage of relapses to be expected can be seen from the 

 following table : — 



With one relapse, 49*2 per cent. 



With two relapses, 20 per cent. 



With three relapses, 5 per cent. 



With four relapses, 2 per cent. ' 



In some cases the attacks may be more prolonged, irregular, 



