Under the auspices of the U.S. Public Health Service and the Navy, Rosenau and his colleagues, in an effort to “determine the mode of spread of influenza,” tried to infect military volunteers with Pfeiffer’s bacillus at a makeshift infirmary on Gallops Island in Boston Harbor. Though human experiments were then seen as acceptable, in a paper later published in
JAMA, Rosenau noted that the team “proceeded rather cautiously at first by administering a pure culture” of the bacterium.
When the “trials proved negative,” he wrote, “we became bolder.” The scientists gave each of the volunteers “a very large quantity of a mixture of thirteen different strains of the Pfeiffer bacillus, some of them obtained recently from the lungs at necropsy.” They also inoculated the men with specimens taken from the throats and noses of influenza patients and later with the patients’ blood. Still no symptoms, so next the volunteers shook hands with, talked with, and were coughed on by the actively ill. They remained healthy.