The Bactericidal Power of Blood and Protection Against Meningococcal Infection

Abstract

In a series of reports (1, 2, 3) Silverthorne and Fraser have presented indirect evidence that the bactericidal power of blood is related to immunity to meningococcal infection. In this communication, further studies on the bactericidal power of blood are presented. A technic for the more accurate measurement of bactericidal power of samples of blood is described and compared to a rotary method. The development of the bactericidal power in the blood of guinea-pigs against the meningococcus has been studied as related to protection against experimental meningococcal infection. Finally, observations on the vaccination of four infants are reported. Technic. The bactericidal test has been modified in the following way. A freshly isolated cerebrospinal fluid strain of the meningococcus, shown to be virulent on the basis of the mouse-mucin-test (3), is used. A fourth or fifth subculture of such a strain of the meningococcus, which has been preserved in a dried state under vacuum, is employed.