110 MILK HYGIENE 



Water from open or thin walled springs or wells 

 may be directly infected by the entrance of water which 

 has been contaminated by the excretions of the sick. 

 [All surface streams are liable to become contaminated 

 either directly or indirectly, through carelessness or 

 imperfect drainage systems. 



Typhoid bacilli may be blown about in dust, carried 

 on the boots of persons who walk over infected surfaces, 

 by small animals and they may also be carried by flies, 

 as was abundantly proven during the Spanish-Amer- 

 ican and the South African wars. Cloths used for 

 washing milk cans may carry this infection. Milk may 

 be infected from the hands of the sick. In one instance, 

 in Philadelphia, it was found that a small milk dealer 

 was in the habit of washing his milk bottles in the family 

 wash tub. Milk has become contaminated during cool- 

 ing, either by a leak in the tubular cooler or by the 

 entrance of water into a submerged can. L. P.] 



Concerning direct or indirect infection from sick per- 

 sons or convalescents, emphasis should be laid upon the 

 fact that the disease often runs so light a course that the 

 diagnosis of typhoid fever is not established ; further, 

 that faeces, and often urine, contain bacilli in great num- 

 ber and that convalescents often have bacteriurea for 

 months after typhoid fever and daily excrete number- 

 less bacilli with the urine. Neuf eld 25 has collected some 

 reports on this subject : of 210 typhoid patients not less 

 than 45 (more than 20%) excreted bacilli with the urine, 

 and Petruschky 26 found that the number of bacilli in the 

 urine exceeded 170,000,000 per c.c. It will be evident 

 to every one who is familiar with existing conditions and 

 customs, especially in the country, that under these 

 circumstances no extreme or unusual carelessness or 



25 Deutches med. Wochenschr., 1890, p. 824. 



26 Zentralbl. f . Bakteriologie, XXIII, 1898, No. 14. 



