day of the disease, and it was quite possible that the specific
germ might have been present at an earlier period and that after a
certain number of days the natural resources of the body are sufficient
to effect its destruction, or in some way to cause its disappearance
from the circulation.

This was the status of the question of yellow fever etiology when Dr.
Reed and his associates commenced their investigations in Cuba during
the summer of 1900. In a "Preliminary Note," read at the meeting of the
American Public Health Association, October 22, 1900, the board gave a
report of three cases of yellow fever which they believed to be direct
results of mosquito inoculations. Two of these were members of the
board, viz., Dr. Jesse W. Lazear and Dr. James Carroll, who voluntarily
submitted themselves to the experiment. Dr. Carroll suffered a severe
attack of the disease and recovered, but Dr. Lazear fell a victim to his
enthusiasm and died in the cause of science and humanity. His death
occurred on September 25, after an illness of six days' duration. About
the same time nine other individuals who volunteered for the experiment
were bitten by infected mosquitoes--i.e. by mosquitoes which had
previously been allowed to fill themselves with blood from yellow fever
cases--and in these cases the result was negative. In considering the
experimental evidence thus far obtained, the attention of the members of
the board was attracted by the fact that in the nine inoculations with a
negative result "the time elapsing between the biting of the mosquito
and the inoculation of the healthy subject varied in seven cases from
two to eight days, and in the remaining two from ten to thirteen days,
whereas in two of the three successful cases the mosquito had been kept
for twelve days or longer." In the third case, that of Dr. Lazear, the
facts are stated in the report of the board as follows:

Case 3. Dr. Jesse W. Lazear, Acting Assistant Surgeon U.S. Army, a
member of this board, was bitten on August 16, 1900 (Case 3, Table III)
by a mosquito (_Culex fasciatus_), which ten days previously had been
contaminated by biting a very mild case of yellow fever (fifth day). No
appreciable disturbance of health followed this inoculation.

On September 13, 1900 (forenoon), Dr. Lazear, while on a visit to Las
Animas Hospital, and while collecting blood from yellow fever patients
for study, was bitten by a _Culex_ mosquito (variety undetermined). As