344 BA CTERIOL OGY. 



mended, in order to favor the free diffusion of oxygen, 

 that the depth of fluid be very shallow. 



Contrary to what might be supposed, bacterium 

 influenza has very little tenacity of life outside of the 

 diseased body. It is destroyed in from two to three 

 hours by rapid drying, and in from eight to twenty- 

 four hours when dried more slowly. Cultures retain 

 their vitality for from two to three weeks. The organ- 

 ism dies in water in a little over a day. As a result of 

 these observations, Pfeiffer does not believe the disease 

 to be disseminated by either the air or the water, but 

 rather by direct infection from the catarrhal secretions 

 of the patients. 



This organism has not been found outside of the 

 human body. In the influenza patient it is present in 

 the catarrhal secretions, bronchial mucous membrane, 

 and the diseased lung-tissues. It may be demonstrated 

 microscopically in the mucus by cover-slip prepara- 

 tions made in the usual way and stained with diluted 

 carbol-fuchsin, referred to above. In the tissues it 

 may be demonstrated in sections stained in the same 

 solution. In the sputum the bacteria are found as 

 masses and as scattered cells. (See Fig. 64.) They are 

 also found within the bodies of leucocytes, especially in 

 the later stages of the disease when convalescence has 

 set in ; at this time they appear as very small, irregular, 

 evidently degenerated bacteria within white blood- 

 corpuscles. They are also present in the nasal secre- 

 tions. 



At autopsies it is advisable to cut out pieces of 

 the diseased tissue about the size of a pea or a bean, 

 break them up in a small quantity of sterile water or 

 bouillon, and make the cultures from this infusion. 



