JAMA 100 Years Ago Section Editor: Jennifer
Reiling, Editorial Assistant.
The investigations of Flügge and his pupils and of others have
shown that in speaking and coughing, droplets of mucus and saliva are expelled
from the mouth and carried for some distance away from their source of origin.
Such droplets have been found to carry bacteria with them. It is especially
in connection with the dissemination of tubercle bacilli that this demonstration
becomes of significance. Recently Koeniger1 has published the results
of extensive studies of bacterial dissemination by droplets from the mouth,
using the bacillus prodigiosus in his tests because of its ready recognizability
from the red pigmentation of its colonies. Persons would rinse their mouths
and throats with suspensions of this bacillus and then, stepping into a specially
arranged room, speak in more or less loud tones for varying periods, the disseminated
bacilli falling on plates of culture-media disposed here and there throughout
the room. In this way coughing, whistling and sneezing were studied as well
as the special effects of repeating the various letters of the alphabet. Consonants—some
more than others—were found to throw out bacteria in greater numbers
than vowels. Koeniger establishes the fact that this mode of bacterial dissemination
takes place over a much wider range of distance than claimed heretofore, the
minute droplets or bubbles sailing far and wide through the atmosphere and
alighting on all sides of the experimenters. The greatest distance to which
bacteria were carried in these experiments was 12.40 meters.
DISSEMINATION OF BACTERIA FROM THE MOUTH DURING SPEAKING, COUGHING, AND OTHERWISE.. JAMA. 2000;284(2):156. doi:10.1001/jama.284.2.156