105 
The various drinking waters used by these cases, as compared with 
those used by all the cases of the 1908 period (see table, p. 47), 
offers an interesting field for speculation as to the part played by 
drinking water in constituting susceptibility to typhoid fever 
infection. 
The 54 cases were distributed among the members of 45 households. 
There were eight instances in w^hich two or more members of the 
same household were affected. The largest number of cases in one 
household w^as three. There were fifteen instances in which the 
members of the household who used milk freely were affected, while 
those who used none or used it more sparingly escaped. 
Most of the cases were among well-to-do persons. 
The sanitary conditions of the residences at wliich the cases 
occurred were as follows: 
Sanitary condition: 
Good 
Fairly good 
Rather bad 
Bad 
Number of cases. 
25 
23 
6 
0 
Total 54 
Many of the cases had a sudden onset of definite symptoms with- 
out recognizable prodromes and many ran a mild course. 
Among the 54 cases there were eight fatalities — mortality rate of 
14.8 per cent, which is rather high for cases due to milk-borne 
infection. 
Among the persons associated with the cases attributed to milk 
infection there were six secondary cases attributed to infection by 
contact with milk cases. 
All but one of these secondary cases were reported subsequent to 
October 31 and are not included in our figures on contact infection. 
The synchronous outbreaks among the customers of these two 
dairymen at once suggested a common source of infection. 
Dairyman No. 59 received milk from two farms. One of these, 
in the District of Columbia, was owned b}/ him and was the location 
of his dairy. The other was the farm of Mrs. X, in Maryland, from 
which he received about 40 gallons of milk daily. 
Dairyman No. 11 received milk from about 22 different farms 
located in Virginia and Maryland. One of the farms supplying this 
dairyman was that of Mrs. X, the same farm which furnished a part 
of No. 59’s supply. From this farm dairyman No. 11 received about 
20 gallons of milk daily. Diagrammatically the situation was as 
follows. 
