The Modifying Effects of Bacterial Substances in the Course of Infection With Neurotropic Virus (I)

The purpose of this paper is to report a part of an exploratory experiment to ascertain the presence or absence of assimilar modifying effect of bacteria or bacterial substances on the course of neurotropic virus infection as that of pneumotropic virus in the natural state.The GD VII strain of mouse encephalomyelitis virus was used as a virus, and Staphylococci, Sarcina lutea, Streptococci, Diplococcus pneumoniae, H. pertussis, Proteus OX19, Brucella abortus Bang, E. Coli, S. Typhi, Shigella dysenteriae, S. cholerae suis, V. cholerae, and Myc. smegmatis were used as bacteria. Groups of 3-4 weeks old mice were inoculated intranasally with cultured bacteria mentioned above, in approximatly 0.03ml two days, and one hour before and two days after, respectively, inoculation with dilutions of GD VII virus by intranasal route under ether anesthesia. The effect of bacteria on the course of virus infection was estimated by the degree of reduction or increase in the LD50 of the experimental group from the level found in a comparable group of mice which had received with sterile broth.The results obtained indicate that Sarcina lutea and S. cholerae suis have the stimulating effect of virus infection and E. coli, H. pertussis, and V. cholerae have the inhibitory effect; E. coli, in particular. The nature of the mechanism of these effects will be clarified in the following extensive studies.