282 GLANDERS 



the subcutaneous tissue and lymphatic glands. The nodules, 

 therefore, in glanders, as Baumgarten puts it, occupy an 

 intermediate position between miliary abscesses and tubercles. 

 The diffuse coagulative necrosis and caseation which are so 

 common in tubercle do not occur to the same degree in glanders, 

 and typical giant cells are not formed. The nodules in the lungs 

 show leucocytic infiltration and thickening of the alveolar walls, 

 whilst the vesicles are filled with catarrhal cells ; there may also 

 be fibrinous exudation, whilst at the periphery of the nodules con- 

 nective-tissue growth is present in proportion to their age. The 

 tendency to spread by the lymphatics is always a well-marked 

 feature, and when the bacilli gain entrance to the blood-stream, 

 they soon settle in the various tissues and organs. Accordingly, 

 even in acute cases it is usually quite impossible to detect the 

 bacilli in the circulating blood, though sometimes they have been 

 found. It is an interesting fact, shown by observations of the 

 disease both in the human subject and in the horse, as well as 

 by experiments on guinea-pigs, that the mucous membrane of the 

 nose may become infected by means of the blood-stream another 

 example of the tendency of organisms to settle in special sites. 



Mode of Spread. Glanders usually spreads from a diseased 

 animal by direct contagion with the discharge from the nose or 

 from the sores, etc. So far as infection of the human subject 

 goes, no other mode is known. There is no evidence that the 

 disease is produced in man by inhalation of the bacilli in the 

 dried condition. Some authorities consider that pulmonary 

 glanders may be produced in this way in the horse, whilst others 

 maintain that in all cases there is first a lesion of the nasal 

 mucous membrane or of the skin surface, and that the lung is 

 affected secondarily. Babes, however, found that the disease 

 could be readily produced in susceptible animals by exposing 

 them to an atmosphere in which cultures of the bacillus had 

 been pulverised. He also found that inunction of the skin 

 with vaseline containing the bacilli might produce the disease, 

 the bacilli in this case entering along the hair follicles. 



Agglutination of Glanders Bacilli. Shortly after the discovery of 

 agglutination in typhoid fever, M'Fadyean showed that the serum of 

 glandered horses possessed the power of agglutinating glanders bacilli. 

 His later observations show that in the great majority of cases of glanders 

 a 1 in 50 dilution of the serum produces marked agglutination in a few 

 minutes, whilst in the great majority of non-glandered animals no effect 

 is produced under these conditions. The test performed in the ordinary 

 way is, however, not absolutely reliable, as exceptions occasionally 

 occur in both directions, i.e. negative results by glandered anmials and 

 positive results by non-glandered animals. He finds that a more delicate 



