Infectious agent from a free-living soil amoeba, Naegleria gruberi.

A subcellular infectious material has been found in a strain of the amoeba Naegleria gruberi, strain EG, which is capable of infecting chick embryo cells and causing them to undergo cytopathic changes with the release of more infectious material. The material is present in two lines of the amoeba which were separated shortly after the isolation of the strain and subsequently maintained in separate laboratories.