RELATION OF A STREPTOCOCCUS TO EPIDEMIC POLIOMYELITIS-Studies in Etiology, Diagnosis and Specific Treatment.

The production in 1915 of herpes zoster or "posterior" poliomyelitis in animals with a streptococcus led to further research on the etiologic importance of streptococci in "anterior" poliomyelitis.A specific streptococcus was demonstrated consistently in persons with poliomyelitis and in well persons having contact with them or merely inhabiting an area in which poliomyelitis was epidemic. That the organism was not present in areas remote from contact with the disease was likewise demonstrated.The streptococcus has been isolated from filtrates of poliomyelitis virus and from the tissues and exudates which harbor the virus. It appears in the spinal fluid in the preparalytic stage of poliomyelitis and disappears from the spinal fluid during the severe stage of the disease. Antibody and antigen prepared from the streptococcus were used to determine the presence of antigen and antibody indicative of streptococcal infection in many patients with poliomyelitis and in well persons. The intensity of reaction indicating specific streptococcal antigen was directly proportional to the degree of paralysis in patients; the reaction was greater in persons whose age, sex and previous isolation from the disease would normally indicate greater susceptibility. The test for antibody gave opposite results. Specific agglutinins for the streptococcus and neutralizing antibody for the virus were present consistently in the serum of persons and monkeys during recovery from poliomyelitis. Virus produced in vitro from the associated streptococcus caused all the clinical and pathologic features of poliomyelitis in monkeys inoculated with it, and the animals that recovered from the disease thus induced were proved to be immune thereafter to the natural virus. Antistreptococcic serum prepared in horses was used to treat poliomyelitis. In a group of monkeys inoculated with the virus of the disease, 6 per cent of those receiving the serum before inoculation died of the disease; of the control group, 82 per cent. In a series of poliomyelitis patients treated with the serum the mortality rate was 8 per cent; in a control series, 21 per cent. In a series treated in all stages of the disease by the author, 10 per cent died; of those who did not receive the serum, 25 per cent. An antibody has been prepared from the streptococcus which appears to prevent paralysis and otherwise mitigate poliomyelitis and to provide immunization from the disease.The conclusion is reached that the virus of poliomyelitis is a form of the specific streptococcus, which is the agent in primary infections and in the development of the immunizing antibody.