The Action of Glycerin on Bacteria in the Presence of Cell Exudates

Glycerin has been employed for a number of years for the conservation of vaccine virus t and other materials of similar nature, e. g., the virus of rabies, clavele, rinderpest, and foot and mouth disease. Its preservative properties for animal and vegetable tissues are also well recognized. It has, however, been employed more as a diluent, particularly in the case of bovine virus, than because of its other properties, as it seemed better adapted for this purpose than the other substances tested. Not only does glycerin possess the property of conserving the activity of vaccine virus for a longer time than any other preservative agent tested, but it has also a marked influence on the bacterial content of the virus. Leoni 2 claims to have discovered this fact as long ago as 1889, and since then he has continually employed glycerin for destroying the bacteria in, as well as for the preservation of, the virus. Notwithstanding Leoni's claim of priority, we have until now given Copeman 3 the credit of pointing out the value of glycerin as a preservative and germicide when added to vaccine virus. Copeman's statements regarding the action of glycerin on the bacteria present in the virus have been accepted by nearly all, if not by all, as final, and have doubtless been the cause of many placing too much confidence in it as a purifier of vaccine, as Rosenau 4 as a result of his study of the subject has already stated.