686 Glanders. 



in the stalls immediately next to that of the affected animal 

 become infected first, although sometimes more remotely located 

 animals are attacked while the intervening ones remain appar- 

 ently perfectly healthy, which, however, does not necessarily 

 exclude the possibility that the latter were not also infected. 

 The disease may merely not have developed as yet to the same 

 degree or may have been completely arrested. In some cases 

 the horse that was the means of introducing the disease may 

 remain in apparently good condition for months and at the same 

 time infect other horses by its expectorated lung secretions or 

 its infected feces. If such cases are not recognized in time they 

 may result in the infection of the greater part of a large stable 

 full of horses, and thus give the disease a firm foothold for years 

 after. 



Diseased horses disseminate the virus of glanders in vari- 

 ous ways. Horses belonging to express drivers, transportation 

 companies and miners and those handled by horse traders and 

 gypsies, in particular, play a very important role in the dis- 

 semination of the disease. Livery stables and country inns 

 often constitute permanent centers of infection, and horses that 

 have been kept in such places over night, or that have been 

 merely fed there or watered may transport the contagion to 

 other places. Finally it is possible also that feed or hay may 

 be the means of transporting the infection from one stable to the 

 other, although infection through these means is necessarily a 

 rare occurrence on account of the slight degree of tenacity pos- 

 sessed by the virus. 



Of all Solidungula the ass is the most susceptible to glan- 

 ders. This animal is very easily infected and usually develops 

 the acute form of the disease. The horse, which is usually 

 affected with the chronic form of the disease, is less susceptible 

 and may recover from its effects. The mule seems to occupy 

 an intermediate position in this respect. Among animals kept 

 under similar conditions and exposed in the same manner a few 

 may be hard to infect, others become lightly infected and 

 recover, while a few individuals seem to be immune. Horses 

 with reduced vitality as a result of other diseases or hard work, 

 or animals in a poor state of nutrition, are more frequently 

 affected than others, but the common occurrence of glanders 

 among horses of this character is in a great measure due to the 

 fact that they are more frequently exposed to infection. 



Camels are easily infected by cohabitation with glandered horses?. Symptoms 

 of the disease, which usually point to affection of the lungs, the nasal mucous mem- 

 brane and the lymph glands, may occasionally appear on the 6th day after exposure. 



The hereditary transmission of the disease is possible but seems 

 to be rare in horses (Valentini observed one instance in which the 

 fetus in a mare was affected in the 9th month of its development), 

 while it is comparatively frequently observed in small experiment 

 animals. This is probably explained by the fact that the bacilli are 



