506 MALTA FEVER 



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 ; here also dead 

 cultures may be used. The reaction appears comparatively 

 early, often about the fifth day, and may be present for a con- 

 siderable time after recovery sometimes for more than a year. 

 Distinct agglutination with a 1 : 30 dilution of the serum in 

 half an hour may be taken as a positive reaction, sufficient for 

 diagnosis. The reaction is, however, usually given by much 

 higher dilutions, e.g., 1 : 500, and even higher. It is to be noted 

 that normal serum diluted 1 : 5 may produce some agglutination, 

 and this property is said to be destroyed at 55 C., whereas the 

 specific agglutinin is not affected. Some observers accordingly 

 recommend that, in applying the test, the serum ought to be first 

 heated to 55 C. 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. 384). 



The Commission has found that vaccination with dead cultures 

 of the micrococcus confers a certain degree of protection amongst 

 those exposed to the disease. As a rule two injections were 

 made, 200-300 million cocci being the dose of the first injection, 

 and about 400 million the dose of the second. The use of vaccines 

 has also been carried out in the treatment of the disease, but 

 the observations are not sufficiently numerous to allow a definite 

 statement to be made as to its value. 



Methods of Diagnosis. During life the readiest means of 

 diagnosis is supplied by the agglutinative test just described 

 (for technique, vide p. 119). 



Cultures are most easily obtained from the spleen either 

 during life or post mortem. Inoculate a number of agar tubes 

 by successive strokes and incubate at 37 C. Film preparations 

 should also be made from the spleen pulp and stained with 

 carbol-thionin-blue or diluted carbol-fuchsin (1 : 10). Cultures 

 may sometimes be obtained from the blood by the usual 

 methods. 



