454 MALTA FEVER. 



Relations to the Disease. — There is in the first place ample 

 evidence, from examination of the spleen, both post mortem and 

 during life, that this organism is always present in the disease. 

 The experiments of Bruce and Hughes show that by inoculation 

 with even comparatively small doses of pure cultures the dis- 

 ease can be produced in monkeys. In these experiments seven 

 animals in all were used, in every case with a positive result. 

 Four died at varying periods of time, after showing well-marked 

 fever, closely resembling in character that occurring in the 

 human subject, and the micrococcus was obtained from the 

 organs post mortem.. The other three animals recovered after 

 suffering from illness with corresponding pyrexia — in two cases 

 extending over two months. The disease has also been pro- 

 duced in the human subject by accidental inoculation with a 

 pure culture of the micrococcus, Birt and Lamb citing three 

 cases, and Strong and Musgrave one case. 



Rabbits, guinea-pigs, and mice are insusceptible to inocula- 

 tion by the ordinary method. Durham, by using the intra- 

 cerebral method of inoculation, has, however, succeeded in 

 raising the virulence so that the organism is capable of produc- 

 ing in guinea-pigs on intraperitoneal injection illness with some- 

 times a fatal result many weeks afterwards. An interesting 

 point brought out by these experiments is that in the case of 

 animals which survive the micrococcus may be cultivated from 

 the urine several months after inoculation. 



Agglutinative Action of Serum. — The blood serum of patients 

 suffering from Malta fever possesses the power of agglutinating 

 the micrococcus melitensis in a manner analogous to what has 

 been described in the case of typhoid fever. This action is 

 manifested throughout the disease, and also for a considerable 

 time after recovery. Wright and Smith found it well marked a 

 year afterwards. They found that the greatest dilution which 

 gives distinct agglutinative effects varies in different cases from 

 I : lo to I : looo. As regards relation to prognosis, the observa- 

 tions of Birt and Lamb and of Bassett-Smith have given results 

 analogous to those obtained in typhoid (p. 343). 



Methods of Diagnosis. — During life the best means of diag- 

 nosis is supplied by the agglutinative test just described (for 

 technique, vide p. 109). 



Cultures are most easily obtained from the spleen either 



