RELAPSING FEVER 211 



animals from relapsing fever, as healthy monkeys usually 

 recover from the disease, whereas if the spleen is removed, 

 the spirilla multiply enormously in their blood, and cause 

 the death of the animal. 



Pathogenesis. — The ages at which the chief number of 

 attacks occur are between fifteen and twenty. The incuba- 

 tion period is about twelve days, and an attack affords little 

 or no protection. In some respects relapsing fever exhibits 

 resemblances to typhus fever, but is admitted on all hands 

 to be a distinct specific disease, as the Spirillwrn Obermeieri 

 is found in all cases of relapsing fever, and in no other cases 

 of disease whatever. 



Eelapsing fever has not recently occurred in this country 

 to any appreciable extent, and is essentially a disease 

 likely to affect persons exposed to unhealthy surroundings 

 and want of food. 



Practical Disinfection. — The excreta and secretions should 

 be disinfected in the same manner as recommended in 

 enteric fever. 



SCARLET FEVER. 



The streptococcus described by Klein in 18853 is probably the specific 

 ' cause of scarlet fever —Distribution of the disease — Mortality greatest 

 in young children — Difficulty of exercising sanitary control owing to 

 the nature of the infective material — Pathogenesis — Epidemics — 

 Successful treatment of cases with Marmorek's antistreptococcic 

 serum. 



Dr. Klein, in the year 1882, described a streptococcus 

 occurring in cases of this disease. He found it in the 

 desquamating particles of skin, in the blood and the sputa 

 of patients. It is non-motile, aerobic or anaerobic ; does 

 not form spores; is killed by drying and by exposure to 

 sunlight in the presence of oxygen. 



