242 CIVIC BIOLOGY 



4. Observed ^ flies swarming on crates of raspberries and black- 

 berries, absolutely open and unprotected (caught about sixty flies with. 

 one sweep of the hand over such a crate). 



Carriers and contact with food. Typhoid Mary was dis- 

 covered by Soper in 1906. She was apparently healthy, but 

 wherever she served as cook typhoid fever was sure to fol- 

 low, and she was found to be alive Avith virulent typhoid 

 bacteria. She had already caused several small and at least 

 one large epidemic. From 1907 to 1910 Mary was detained 

 in the isolation hospital of the New York Board of Health 

 and then was released upon her promise to change her occu- 

 pation. Early in 1915 an epidemic of 25 cases broke out 

 in one of the New York hospitals, and there in the kitchen, 

 under an assumed name, was found Typlioid INIary. 



About 4 per cent of those who recover from the disease 

 remain as typhoid carriers, either continuously or intermit- 

 tently, and some may not even know that they have ever 

 had typhoid at all. For some unaccountable reason there 

 are about five Avomen carriers to one man. A typhoid epi- 

 demic occurred at Hanford, California, INfarch, 1914, the 

 study of which by the health officers proved most instruc- 

 tive. A church dinner, of which 150 partook, resulted in 

 93 cases and 3 deaths. The infection was traced to a Avoman 

 Avho had cut the bread and prepared a dishpan of Spanish 

 spaghetti. She had nursed her daughter through typhoid 

 thirty-fiA^e years before, but did not knoAV that she herself 

 had CA^er had the disease. In order to test the matter a 

 dish of spaghetti, not so large, was similarly prepared, and, 

 although baked much more thoroughly than that served at 

 the dinner (until the top Avas broAvn, the points on the sur- 

 face Avere charred, and the edges were boiling furiously) 

 living typhoid bacilli Avere found Avithin half an inch of the 



1 In a public market, Washington, D.C., July 3, 1915. 



