Infantile Paralysis or Acute Anterior Poliomyelitis 245 
spite of these precautions, all their results were negative, none of the 
inoculated animals having contracted poliomyelitis. They also 
experimented with bedbugs which had fed upon infected patients at 
various stages of the disease, but the results in these cases also were 
wholly negative. 
Kling and Levaditi considered at length the possibility of trans¬ 
mission of the disease by Stomoxys. As a result of their epidemiologi¬ 
cal studies, they found that infantile paralysis continued to spread 
in epidemic form in the dead of winter, when these flies were very 
rare and torpid, or were even completely absent. Numerous cases 
developed in the northern part of Sweden late in October and 
November, long after snow had fallen. On account of the rarity 
of the Stomoxys flies during the period of their investigations they 
v r ere unable to conduct satisfactory" experiments. In one instance, 
during a severe epidemic, they found a number of the flies in a stable 
near a house inhabited by an infected family, though none w r as 
found in the house itself. These flies were used in preparing an 
emulsion which, after filtering, was injected into the peritoneal 
cavity of a monkey. The result was wholly negative. 
As for the earlier experiments, Kling and Levaditi believe if the 
flies w r ere responsible for the transmission of the disease in the cases 
reported by Rosenau and Brues, and the first experiments of Ander¬ 
son and Frost, it w r as because the virus of infantile paralysis is elimi¬ 
nated with the nasal secretions of paralyzed monkeys and the flies, 
becoming contaminated, had merely acted as accidental carriers. 
Still further evidence against the hypothesis of the transmission 
of acute anterior poliomyelitis by Stomoxys calcitrans was brought 
forward by Sawyer and Herms (1913). Special precautions were 
used to prevent the transference of saliva or other possibly infectious 
material from the surface of one monkey to that of another, and to 
avoid the possibility of complicating the experiments by intro¬ 
ducing other pathogenic organisms from wild flies, only laboratory- 
bred flies were used. In a series of seven carefully performed experi¬ 
ments, in which the conditions were varied, Sawryer and Herms were 
unable to transmit poliomyelitis from monkey to monkey through 
the agency of Stomoxys, or to obtain any indication that the fly is the 
usual agent for spreading the disease in nature. 
The evidence at hand to date indicates that acute anterior polio¬ 
myelitis, or infantile paralysis, is transmitted by contact with in¬ 
fected persons. Under certain conditions insects may be agents in 
spreading the disease, but their role is a subordinate one. 
