24 
TYPHOID FEVEK IH DISTRICT OF COLUMBIA. 
findings in 185 (92.5 per cent) of the patients, these slight increases 
can hardly be considered of importance. 
The general conclusion is therefore reached that, contrary to Gui- 
art’s view, neither whipworms nor other intestinal worms play any 
essential role as inoculating agents in this disease. 
THE WELL WATERS. 
The waters of the shallow wells have frequently been regarded as 
a means of conveying the infection of typhoid fever, and, as there are 
63 shallow wells in the District of Columbia used by the public, we 
have made a particular study of this phase of the subject. 
The waters of 87 public wells are used for drinking purposes in the 
District of Columbia. Twenty-four of these wells are ^^deep” and 
63 are shallow. ” As will be seen from our report, the water of the 
deep wells has been found to be of excellent quality, both chemically 
and bacteriologically. Some of these so-called ‘^artesian’’ wells are 
practically sterile, and no evidence was found of fermenting organ- 
isms. On the other hand, both the bacteriological and chemical 
examinations indicate quite a different condition in the case of the 
shallow wells. Of the 63 shallow wells now used by the public 31 
show indications of sewage pollution, 29 are waters of suspicious 
character, and only 3 show no evidence of pollution. 
Our studies developed, further, that the water of many of the 
shallow wells varied widely from time to time, both in chemical com- 
position and in the number and character of the bacteria present. 
This in itself is a dangerous indication from a sanitary standpoint, 
showing an intermittent source of surface contamination or sewage 
pollution. 
It is also evident from a study of our data that there is a relation 
between the proximity and number of privies and the bacteriolog- 
ical and chemical findings of the well waters. It was found, further, 
that most of the wells with broken pumps and leaky platforms, per- 
mitting surface contamination, often disclosed this condition by the 
laboratory analyses. On the other hand, our epidemiological studies 
revealed no special grouping of typhoid cases about any particular 
well, and no definite relation could be discovered between the use of 
any particular well water and the occurrence of typhoid cases. This 
is no guarantee that some of these shallow wells have not been 
infected in past years and will not again become so in the future. 
The infection of a shallow well is usually temporary. 
It is evident that a densely inhabited area with miles of sewers, 
some of them doubtless broken or leaky, and with almost 4,000 priv- 
ies must produce a more or less polluted condition of the soil, ren- 
dering the ground water unfit for drinking purposes. On general 
sanitary principles alone shallow wells and privies have been elimh 
