ACUTE ANTERIOR POLIOMYELITIS 557 



pleuropneumonia of cattle and of poliomyelitis have been cultivated 

 on artificial media; thus far the remainder have resisted attempts at 

 cultivation. 



Acute Anterior Poliomyelitis. Epidemic Poliomyelitis. Epidemic 

 poliomyelitis is an acute disease observed more frequently in children, 

 although adults are by no means immune. The onset is usually 

 abrupt, although in some cases the earliest symptom is fever, with 

 or without sore throat. The most striking feature is a paralysis of 

 one or more limbs, which may be the first clinical indication of the 

 disease. The principal lesion of the earlier stages is a hyperemia of 

 the vessels of the cord together with thrombosis, and leukocytic infil- 

 tration of the perivascular lymph spaces, more commonly in the 

 cervical and lumbar regions, and in the spinal fluid as well. The older 

 lesions are essentially a degeneration of the ganglion cells, particularly 

 of the anterior horn, and eventually their atrophy. The motor nerves 

 appear to suffer most there are few, if any, indications of sensory 

 disturbance. The relation of the disease to Landry's ascending 

 paralysis, if any, is unknown. 



The etiology of acute anterior poliomyelitis was for many years a 

 matter of conjecture. In 1909, however, Landsteiner and Popper 1 

 transmitted the disease to two monkeys through the injection of a 

 saline emulsion of the spinal cord from an acute case. The animals 

 developed paralysis of their limbs, and were killed and studied bac- 

 teriologically and pathologically. The lesions were similar to those 

 found in human cases; the cultures were wholly negative. An attempt 

 to introduce the disease in other monkeys by the injection of material 

 from the two successfully inoculated animals proved futile. They 

 believed the virus belonged to the group of filterable viruses. Flexner 

 and Lewis 2 and Landsteiner and Levaditi 3 soon confirmed the filter- 

 able nature of the virus, and Flexner and Lewis succeeded in trans- 

 mitting the virus through a succession of monkeys. The success of 

 their transmission lies in the choice of inoculation site intracerebral 

 inoculations are reliable, but intraperitoneal injections are usually 

 barren of results. Of great importance are the observations of Flexner 

 and Clark 4 and Osgood and Lucas 5 that the virus may survive in the 

 mucosa of the nasopharynx of infected monkeys for several weeks. 



1 Ztschr. f. Immunitatsforsch., 1909, ii, 378. 



2 Jour. Am. Med. Assn., 1909, liii, 2095. 



3 Compt. rend. Soc. biol., 1909, Ixvii, 592. 

 4 Proc. Soc. Exper. Biol. and Med., 1912, 13, x, 1. 

 5 Jour. Am. Med. Assn., 1911, Ivi, 495. 



