596 MICROBIOLOGY OF THE DISEASES OF MAN AND ANIMALS. 



body. A local suppuration may be the only result or it may be followed 

 by a general septicaemia condition. 



In erysipelas some local injury is also probably necessary as a starting- 

 point. 



Following the local establishment of streptococci sufficient toxin is 

 elaborated to produce greater or less systemic disturbance. If a sep- 

 ticaemia supervenes the poisoning becomes extreme and the organisms 

 are distributed throughout the body. 



Immunity following recovery from natural streptococcic infection is 

 very slight if any, and never of a permanent sort. Septicaemias once 

 established are generally fatal, and erysipelas can recur frequently. 



Bacterial substances, opsonins, agglutinins and precipitins have been 

 demonstrated in immune sera, which, however, show no therapeutic 

 success. 



Streptococci are eliminated in the discharge of local infections in 

 sputum, etc., and are then probably more virulent. Infection by contact 

 from such sources is particularly dangerous. In anginas and strepto- 

 coccic infections of the respiratory tract, the epidemiology is practically 

 the same as for diphtheria and pneumonia. Similarly erysipelas is to be 

 treated as a contagious disease. 



In the prophylaxis of streptococcic diseases, greatest care must be 

 shown where chances of infection by the virulent strains are possible 

 Isolation of erysipelas is universally practised in hospitals. Similarly 

 cases of puerperal sepsis and any local disease should be kept from con- 

 tact with other puerperae. Streptococcic pus from all sources is to be 

 carefully destroyed. 



Streptococci seem to be always present on the exposed surfaces of the 

 body and are probably capable of giving trouble should any local lowered 

 resistance occur. The prevention of this may be accomplished by strict 

 antiseptic treatment of wounds. 



PNEUMONIA.* 

 Streptocococcus pneumonias. 



The occurrence of a diplococcus in the large majority of cases especially 

 of the lobar type of pneumonia, has caused this coccus to be regarded as 

 practically specific and warrants the name of Micrococcus pneumonia, 



* Prepared by Edward Fidlar. 



