https://stacks.cdc.gov/view/cdc/67902
CDC: Public health reports ; v. 34, no. 2, January 10, 1919
Some Interesting though UNSUCCESSFUL attempts to transmit Influenza experimentally
These experiments were carried on jointly by Lieut. Commander M. J. Rosenau, Medical Corps, U.S.N.R.F., and Lieut. W.J. Keegan, Medical Corps, U.S.N.R.F. and by Surg. Joseph Goldberger and Asst. Surg. G.C. Lake, United States Public Health Service, at the United States Quarantine Station, Gallop's Island, Boston, Mass.
The subjects of experiment were 68 volunteers from the United States Naval Detention Training Camp, Deer Island, Boston.
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At the time the volunteers were exposed to this infection the cases were from 10 to 84 hours from the onset of their illness and 4 of them were not over 24 hours after the onset.
Each volunteer conversed a few minutes with each of the selected patients, who were requested to, and coughed into the face of each volunteer in turn, so that each volunteer was exposed in this manner to all 10 cases.
The total exposure amounted to about three-quarters of an hour for each volunteer.
None of these volunteers developed any symptoms of influenza following this experiment.
Weird, very weird...