STUDIES ON THE TYPES OF TSUTSUGAMUSHI OF AGENT BY CROSS-IMMUNIZATION TEST (Ⅱ)

Cross-immunization-tests were performed in mice injected with Nitrogen-mustard-N-oxide (NNO) intraperitonealy among many strains of R. tsutsugamushi are strains of Ozeki, Mitani, Tanisawa and ⅩⅩⅡ. Concerning with dosis of drug, NNO was used 0.4 mg per day and used 1-4 times. 1) Ozeki strain, Mitani strain and ⅩⅩⅡ strain are similar in its antigenic structure than Hichito and Tanisawa strains. 2) Hichito and Tanisawa strains are similar in its antigenic strueture than Ozeki, Mitani and ⅩⅩⅡ strains.