恙虫病病毒の性質変換に関する研究殊に変異病毒株の固定性について 第1編 変異恙虫病病毒ワクチンの感染防禦賦与能の消長と変異病毒株の病原性の消長について

It has been stated already that the change on the properties of tautsugamushi disease rickettsia was occured by a contineous action of small amount of chloramphenicol in the body of mouse. The author studied the properties of the varied rickettsia in order to identify whether the changed property could be fixed or turned back to that of the original rickettsia. The following results were obtained. 1) In a high temperature season the pathogenicity of the varied rickettsia to the chlorpromazine-treated guinea pig was moderated or lost completely by serial passage through normal mouse at least 10 generations. 2) After each passage of the rickettsia on normal mouse, the ascitic vaccine was prepraed by inoculating the rickettsia into the chlorpromazine-treated guinea pig. The ascitic vaccine thus obtained was gradually increased the prophylactic capacity and the vaccine injected animal became to render the type specific immunization against the infection of the original rickettsia. Hence, it was found the reversibility of the occured change on the properties of the tsutsugamushi disease rickettsia by action of chloramphenicol.