276 BACILLUS TYPHOSUS. 



Unhygienic surroundings are also an important factor in the 

 causation of typhoid fever. Damp, dark, and dirty houses, 

 and tenements especially, undermine the natural resisting 

 power of the individual, and he more readily falls a prey to 

 infections, particularly typhoid fever, which is a filth disease. 

 Personal cleanliness means health and the power to ward off 

 infections. 



After the typhoid bacillus has gained entrance to the intes- 

 tinal canal it lodges in the Peyer's patches and the solitary 

 lymph-follicles in the mucosa of the bowel. Here it multi- 

 plies and produces the local symptoms of the disease. The 

 infection travels through the lymphatics to the mesenteric 

 lymph-glands, the spleen, liver, and kidneys. The bacillus 

 may also make its way into the blood-current and into the 

 bone-marrow and distant parts of the body. The bacilli have 

 also been found in the rose spots. It is possible to make pure 

 cultures of Bacillus typhosus from the blood and from the 

 rose spots. 



The urine frequently contains the bacilli, especially when 

 the kidneys have been involved. The urine may be the 

 source of infection. Even after convalescence, for as long as 

 two or three weeks, the urine may contain the bacillus. It 

 is fully as important to disinfect the urine thoroughly as it is 

 to disinfect the feces. 



The typhoid bacilli can always be found in the gall-bladder ; 

 occasionally in the lungs, meninges, heart, and testicles, espe- 

 cially when these organs are the seat of typhoid complications. 

 The bacillus has been found in an abscess of the brain, and 

 in other suppurative lesions that have developed in the course 

 of or after an attack of typhoid fever. 



The lymphatic hyperplasia seen so frequently in the internal 

 organs, especially the liver and spleen, is due to the toxin 

 elaborated by the typhoid bacillus. It was at one time 

 assumed that the typhoid bacillus never left its habitat in the 

 intestinal canal, and that the various complications were due 

 to the toxin. This opinion is not held now, as the bacillus 

 has been found and identified in the complicating lesions of 

 typhoid. 



Puncture of the spleen has been advocated as a means of 



