GLANDERS GROUP 253 



characteristics in its early stages; the lymph-nodes in various 

 parts of the body become infected and enlarge. This may exist 

 for a long period in an animal, and may terminate finally in an 

 acute attack. The lesions in the chronic type are generally present 

 on the nasal mucosa, in the lungs, and in the lymph-glands. The 

 nodular glanders of the nasal mucosa is the most frequent type. 

 The nodules, small at first, enlarge to the size of a pea, then break 

 down, suppurate, and form chronic ulcers. When healing of the 

 deeper ulcers occurs, the scar resulting is quite characteristic. 

 In the lungs lesions are almost invariably to be found ; these may be 

 nodular, or consist of infiltration of considerable areas of tissue. 

 In farcy or cutaneous glanders the nodules form in the skin; 

 the lymph-vessels become swollen and feel like a string of 

 beads or a knotted cord. These nodules usually break through 

 to the surface and ulcerate. In man the organism commonly 

 gains entrance through abrasions or wounds in the skin, or 

 by inhalation, and the infection produced is practically always 

 fatal. 



Immunity. No toxins have been demonstrated for Bacillus 

 mallei, although endotoxins are produced. Agglutinins are pres- 

 ent in the blood-serum of normal animals, but in much greater 

 concentration in the blood of infected animals. Precipitins 

 may also be demonstrated. Of the bactericidal and opsonic 

 nature of sera less is known. 



Active Immunization. Immunization by the use of suspensions 

 of dead bacteria or their products (mallein) has been attempted 

 both in prophylaxis and cure. Although some favorable results 

 have been reached, the subject needs further study. No method 

 of vaccination or active immunization has as yet been shown to be 

 practical and successful. 



Passive Immunization. The blood-serum of animals, such as 

 the ox, naturally immune to glanders has been claimed to possess 

 immunizing power when injected into smaller laboratory animals, 

 as the rabbit. No practical utilization has been made of this, and 

 the fact itself is in need of further study. 



Bacteriologic Diagnosis. A presumptive bacteriologic diag- 

 nosis may be made by an examination of properly stained pus 

 or sections of tissue, and a more positive diagnosis by the meth- 



