A Bacteriophage Active Against a Virulent Hemolytic Streptococcus.

Abstract

We reported1 last year the finding of a bacteriophage against a virulent hemolytic streptococcus. Such a lytic principle active against streptococcus has been reported so rarely, if at all, that it seems desirable to state our results in some detail.The organism against which the phage was originally active was isolated about 3 years ago from a spontaneous fatal infection in a stock rabbit. At autopsy, the animal showed marked thoracic lesions, myocarditis, pericarditis, bronchopneumonia, fibrino-purulent pleurisy, extensive empyema with relatively little grossly noticeable below the diaphragm save an acute splenic tumor. The organism was readily obtained in pure culture from these lesions and also from the heart's blood. It grows on sheep blood agar as a very moist, translucent, mucoid colony, somewhat similar to that of Pneumococcus mucosus, but it produces a wide zone of hemolysis on the plate. One cc. of a 12 hour broth culture will cause complete hemolysis of a 5 per cent suspension of washed sheep r...