130 THE HOUSE FLY—DISEASE CARRIER 
Tenth German Army Corps in the summer of 1909 
was traced to a chronic carrier in the case of a woman 
who prepared vegetables and who had assisted in the 
preparation of vegetable salads. The typhoid bacillus 
grows on the surface of potatoes readily, and this ac¬ 
counted for the outbreak, on the necessary supposition 
that the woman was of uncleanly habits. The curious 
point in this case was that she had had typhoid thirty- 
six years previously for the only time. In the same 
summer there was an epidemic of the fever in George¬ 
town, D. C. This was traced by milk routes to a cer¬ 
tain milk dealer, who was a woman and who on ex¬ 
amination was shown to be a chronic carrier. 
In the same year, Aldrich, in the Journal of the 
Royal Army Medical Corps for September, page 225, 
made the generalization that the combined observations 
of a large number of investigators in various countries 
showed that about three per cent, of the convalescent 
typhoid patients become chronic carriers, and of these 
eighty per cent, are women. About this time the Ger¬ 
man Government conducted an anti-typhoid campaign 
in Southwest Germany, and in his report Klinger 
/ showed that 400 chronic carriers were found and that 
there were probably others. 
Earlier than this, Dr. W. G. Savage (1907) made 
three points of interest in this connection: (1) Ty¬ 
phoid bacilli are frequently excreted in the urine in 
about twenty per cent of the cases, but the obvious 
practical measures resulting from this knowledge are 
not habitually taken. (2) Typhoid bacilli may persist 
