Experiments on the Cultivation of the Microorganism Causing Epidemic Poliomyelitis

Several attempts have been made to demonstrate under the microscope and to develop in artificial cultures the microSrganism causing epidemic poliomyelitis, but hitherto unsuccessfully.Giersvold 1 cultivated certain micrococci from the cerebrospinal fluid, and Fox 2 a bacillus from the circulating blood of poliomyelitic patients, but both have now been discredited as causes of the disease.The discovery of the filterable nature of the causative agent independently by Flexner and Lewis 8 and Landsteiner and Levaditi 4 not only disposed finally of the claims made for the above mentioned bacteria, but also discouraged renewed efforts at cultivation.Flexner and Lewi# noted and Levaditi 6 confirmed a clouding of serum bouillon by an aqueous Berkefeld filtrate of the central nervous tissues of poliomyelitic monkeys, but the phenomenon proved to be due to protein precipitation and not to multiplication of a living parasite.Proescher 7 has recently stained certain coccus-like bodies in films prepared from the central nervous organs of monkeys infected experimentally with the virus of poliomyelitis.The precise nature of these bodies has stil,1 to be worked out; ap-*