The Size of the Virus of Rabies (“Fixed” Strain) by Ultrafiltration Analysis

Abstract

Discussion and summaryThe filtration end-point of 0·2μ leads us to assign according to Elford (1933) a value 100—150 mμ. for the particle diameter of the virus of rabies. This figure we have previously reported inAnn. Report Med. Res. Council(1934) and also in a discussion held by the Royal Society of Medicine (Galloway, 1936). Recently the Japanese workers, Yaoiet al.(1936), using similar graded collodion membranes (gradocol) and the same general technique as employed in the present experiments, have studied independently another strain of “fixed” rabies virus “Fukuoka”. Their stock filtrates appear to have been more potent than ours, their figures for the limiting infective dilution being 10–3to 10–4. The incubation period in rabbits inoculated with the “Fukuoka” strain is also shorter than in the case of rabbits inoculated with Pasteur Institute (Paris) strain. Even so, they find exactly the same value for the filtration end-point 0·2 μ as found by us for the Pasteur strain, thus indicating the particle size of these two “fixed” strains of rabies virus to be the same.