Infantile Paralysis or Acute Anterior Poliomyelites 243 
The experiments referred to were earned on during the summer of 
1912 and in September Dr. Rosenau announced that the disease was 
transferred by the bite of the stable-fly. 
A monkey infected by inoculation was exposed to the bites of 
upwards of a thousand of the Stomoxys flies daily, by stretching it 
at full length and rolling it in a piece of chicken wire, and then placing 
it on the floor of the cage in which the flies were confined. The flies 
fed freely from the first, as well as later, after paralysis had set in. 
Alternating with the inoculated monkey, healthy monkeys were 
similarly introduced into the cage at intervals. New monkeys were 
inoculated to keep a supply of such infected animals and additional 
healthy ones were exposed to the flies, which fed willingly and in 
considerable numbers on each occasion. “Thus the flies were given 
every opportunity to obtain infection from the monkeys, since the 
animals were bitten during practically every stage of the disease 
from the time of the inoculation of the virus till their death follow¬ 
ing the appearance of paralysis. By the same arrangement the 
healthy monkeys were likely to be bitten by flies that had previously 
fed during the various stages of the disease on the infected monkeys. 
The flies had meanwhile enjoyed the opportunity of incubating the 
virus for periods varying from the day or two which usually elapses 
between consecutive feedings, to the two or three-week period for 
which at least some (although a very small percentage) of the flies 
lived in the cage.” 
“In all, twelve apparently healthy monkeys of a small Japan 
species were exposed to the flies in the manner described for the in¬ 
fected monkeys. Some were placed in the cage only once or twice 
and others a number of times after varying intervals. These ex¬ 
posures usually lasted for about half an hour, but were sometimes 
more protracted. No results were apparent until two or three 
weeks after the experiment was well under way, and then in rather 
rapid succession six of the animals developed symptoms of poliomye¬ 
litis. In three, the disease appeared in a virulent form, resulting 
in death, while the other three experienced transient tremblings, 
diarrhoea, partial paralysis and recovery.” — Brues, 1913. 
Very soon after the announcement of the results of experiments 
by Rosenau and Brues, they were apparently conclusively confirmed 
by Anderson and Frost (1912), who repeated the experiments, at 
Washington. They announced that through the bites of the Stomoxys 
flies that had previously fed on infected monkeys, they had succeeded 
in experimentally infecting three healthy monkeys. 
