The action of soaps on the pneumococcus

Abstract

The object of the study to be reported briefly is the ascertaining of the manner in which the pneumococcus is disposed of in the body of infected animals that recover. The animal experiments were made on full grown rats. A strain of pneumococcus fatal to them in 1/10,000 of a cubic centimeter of a twenty-four hour bouillon culture was employed. Strong solutions (1 to 5 per cent.) of soap (sodium oleate) precipitate the diplococci in an adherent mass which afterwards undergoes complete solution in water or salt solution. Solutions of soap of a strength of 1 to 10,000 do not produce visible changes in the bacterial suspensions but reduce slightly the number of viable cocci. Solutions of 1 to 15,000 or 1 to 20,000 do not affect the viability in cultures but reduce somewhat the virulence. At the same time the diplococci appear somewhat swollen but not otherwise altered.