Experimental Poliomyelitis

Abstract

The epidemic of poliomyelitis in New York and New England in 1931 presented an opportunity for controlled studies^{1, 2} to determine the value of convalescent and other immune serums, administered in the preparalytic stage of the disease. In these reports the authors were unable to present statistical evidence that such serums were of value, either in reducing the death rate or in preventing paralysis. Since experience with virus diseases indicates that little is to be expected from the use of immune serums, once the disease has become established in the organism, it becomes important to determine the extent of involvement, particularly of the central nervous system, in the preparalytic stage of poliomyelitis.

In this study, an effort was made to determine the early pathology in the experimental disease, following intranasal instillations of the virus. The close analogy between experimental poliomyelitis and the human disease should make any findings in the former significant in their application to the latter.

We have recently succeeded in obtaining a nasal strain of virus∗ which has successfully infected every animal. This mode of infecting the experimental animal is the probable mode of infection in man, and eliminates the trauma incident to intracerebral inoculation.

Method. Six Macacus rhesus were simultaneously inoculated in-tranasally on 3 successive days with a 10% centrifuged suspension of cord in distilled water. 1 cc. of the suspension was instilled into each nostril. Temperatures were taken twice daily and the animals observed for evidence of illness. They were sacrificed in the following order: The first animal 24 hours after the third instillation, and one animal each day thereafter until the 6 had been killed. The animals were killed with chloroform and autopsies performed immediately.