41 
THE PARALLELISM IN THE TYPHOID DEATH RATES OF RICH- 
MOND, VA., AND WASHINGTON, D. C. 
Lew and Freeman ® recently have contributed a very interesting 
report on typhoid feyer in Kicliniond, Va. They conclude that but 
a small part of Richmond’s typhoid feyer is due to the pubhc water 
supply and that — 
The death rate from typhoid fever in Richmond, certainly for the past few years, 
has been almost entirely the “residual” or “prosodemic ” rate of northern cities, made 
larger than in the North by reason of the greater length and intensity cf the hot season, 
during which, both North and South, there is normally a mai’ked increase in the 
typhoid death rate. A considerable part of this residual rate in Richmond is due to 
the large number of dry closets. 
They present a chart sliowng a striking and really remarkable 
parallehsm in the typhoid death rate of Richmond and TTasliington 
since 1880. We reproduce their chart wth the typhoid death rate of 
Baltimore for corresponding years, and the rate of Richmond and 
Washington for 1908 added thereto. (See Chart Xo. 8.) 
The authors argue that the fluctuations in the typhoid feyer death 
rate of Wasliington were not due to changes in the water supply, 
because astoundingly parallel fluctuations occurred in the rate of 
Richmond, whose water supply during the entire period was practi- 
cally unchanged, and they follow the argument with the statement 
that — 
We are reduced, so far as the writers can see, absolutely to the theory that there 
must be some little understood influences of a very widespread character, varying 
from year to year, which play a more important role in (he epidemiology of tj’phoid 
fever than has as yet been discovered. 
The curve for Baltimore does not fall in hue in this remarkable 
parallehsm, which greatly comphcates the problem and the conclu- 
sions to be draym from the curves. 
Richmond and Washington, though obtaining their water supplies 
from different rivers still obtain water of the same general character — 
that is, surface river water exposed to very similar chmatic conditions 
and to about corresponding diluted sewage pollution. 
Baltimore obtains water of different character — lake water obtained 
from a fairly well protected watershed and then subjected to long 
storage. Baltimore’s typhoid death rate from 1880 to 1907 was 
continuously lower than those of Riclunond and Washington. In 
1907 for the first time Baltimore’s rate was higher than Washington’s. 
a Le\’y, Ernest C., and Freeman, Allen W. : Certain conclusions concerning t^’phoid 
fever in the South, as deduced from a study of typhoid fever in Richmond, Va. Old 
Dom. joum. med. and surg., vol. 7, Nov., 1908. 
