Experiments on the Filtrability of the Rosenow Streptococcus of Anterior Poliomyelitis

Abstract

This paper deals with the successful filtration through Berkefeld candles of 2 strains of the Rosenow anterior poliomyelitis streptococcus. These strains were designated 1630.30 and 1694 1 .50. 0.5 cc. of a 20-hour brain infusion broth culture of 1630.30 was inoculated intracerebrally into each of 3 rabbits. Two of these animals died in less than 24 hours, and the third in 36 hours. Autopsies showed typical cerebral meningitis. From cultures of the brain, meninges, and cerebral exudate, the original streptococcus was recovered in each case. Heart blood cultures were negative.

The brains of these 3 animals were emulsified in broth and 0.5 cc. reinoculated intracerebrally into fresh rabbits. Death again resulted in approximately 18 hours, with recovery of the streptococcus. Animals inoculated with 0.5 cc. of the Berkefeld N filtrate of these emulsions suffered no ill effects. By intensive cultivation of these 3 brain emulsion filtrates using the Hauduroy transplant method on blood agar plates, we were able to recover from 2 of them an organism resembling both microscopically and culturally the 1630.30 streptococcus. In all cases it appeared on the 4th to 6th plate in the series.

Identically this same procedure was carried out using the 1694 1 .50 strain Three rabbits were inoculated intracerebrally. All showed meningitis symptoms but only one died (48 hours). The streptococcus was recovered from brain cultures of this animal, but not from the heart blood. An organism believed to be 1694 1 .50 was also recovered from the brain filtrate in the same way as for the 1630.30 strain.

Then each of the 4 strains was treated in the following manner: 20 cc. of a 24-hour hrain heart infusion hroth culture was injected intraperitoneally into a small half-gronn rahlit and 50 cc. into a large rabbit.