82 APPLIED BACTERIOLOGY FOR NURSES 



they cause ulceration, and this frequently involves the 

 blood-vessels, giving rise to severe hemorrhages. Some- 

 times the ulceration passes entirely through the intes- 

 tinal wall, and this is called a perforation. With the 

 escape of fecal matter into the peritoneal cavity comes 

 the development of peritonitis. In many cases the 

 typhoid bacilli are found not only in the feces but also 

 in the urine. This is important to remember in guarding 

 against infection of others. 



In the country, where privies and cesspools are com- 

 mon, it often happens that typhoid stools insufficiently 

 disinfected find their way into a well, spring, or stream, 

 and so lead to the infection of others. In summer, when 

 flies abound, it sometimes happens that flies carry 

 infected material from such a privy directly into 

 the kitchen, and deposit typhoid bacilli on the food 

 standing about. If a pitcher of milk thus becomes in- 

 fected, the bacilli at once thrive and multiply so that in a 

 very short time the milk contains enormous numbers 

 of typhoid bacilli. Some infections have been traced 

 to the washing of dairy utensils — cans, etc. — in typhoid- 

 infected water. Other cases have been caused by un- 

 recognized mild cases, especially when the latter had 

 something to do with the handling of food. In the 

 city a large number of cases are undoubtedly due to 

 quite direct infection from a previous case. It is now well 

 established that oysters taken from beds polluted with 

 sewage may carry typhoid infection. This is more apt 

 to happen with oysters which have been "fattened" in 

 sewage-polluted water. It is advisable, therefore, to eat 

 no oysters which have been "fattened"; the lean, gray 

 oyster is always to be preferred. When a patient re- 



