BACTERIAL DISEASES OP THE ANIMAL KINGDOM 123 



of animals that have died of this disease are full of them, so that such 

 carcases also spread the disease, unless treated to prevent further 

 infection. It has, however, been found that in the process of putre- 

 faction the anthrax bacilli succumb rapidly when in competition with 

 the putrefactive bacteria. 



The disease known as Glanders is commonest among horses and 

 allied animals, e.g. mules and asses. In man it is the result of direct 

 inoculation from an animal through a skiri wound, so that the disease 

 is chiefly found among people who have much to do with horses. 

 The organism which is responsible for this disease is named Bacillus 

 mallei, and consists of short rods with rounded ends of about the same 

 size as those of Bac. tuberculosis. They are about 0-3 /x in breadth 

 and about 3'0/i in length. Sometimes filamentous rods 8-12 /i long are 

 to be found in a culture of this bacillus. Spore formation is unknown. 

 The bacilli can retain their vitality for 14 days, sometimes longer, when 

 not interfered with, but are easily killed by heat and disinfectants. 

 Glanders is very like tuberculosis in its action and general character. 

 It spreads from a diseased animal by direct contagion from the nose or 

 from sores. So far as is at present known infection through the 

 medium of air to man does not take place. The poison secreted by 

 this organism has been prepared in an impure condition, and is known 

 as mallein. This is used in inoculation of animals for preventive pur- 

 poses, the poison being administered in such a way that a mild attack 

 of the disease takes place. This renders the subject immune so far as 

 this disease is concerned. Another disease organism belonging to the 

 same group of bacteria is Bacillus influenzeae. During an attack of 

 influenza the bacilli are found in large numbers in 

 the nasal secretion, and in still larger numbers in • 



the masses of greenish-yellow sputum from the " 9 



bronchi, where they occur almost in a state of B '^^^ 

 purity. They are small, being only 0-3 /i broad B ^ M 

 and not more than l'5yu. long (Fig. 76). We do 

 not know much of this bacillus, and the chief evi- Fi". 76.— influenza 



bacillus. 



dence of its casual relation to the disease is based 

 on the fact that it is always present in these nasal and bronchial 

 secretions during an attack of influenza. Like tetanus and tuber- 

 culosis, the bacillus is confined to certain areas, from which doubtless 

 the toxin is distributed to other portions of the body. Much 

 information cannot be obtained, because, so far as is known, all the 

 lower animals are immune against this disease. With regard to 

 the contagiousness of influenza, it is known that the resistance of 



