抄録
Tsutsugamushi disease and its etiological agent, Rickettsia tsutsugamushi, were discovered by Japanese pioneers, followed by its appearance not only almost everywhere Japan, but also in China and Southeast Asia. The incidence of the disease in our country decreased after the Second World War and, between 1965 and 1975, only a few patients were detected. However, since 1976, the number of patients with this disease in Japan started to increase and, recently about 900 patients were dectected every year. In the initial part of this review, the author refers to the recent profile of Tsutsugamushi disease in Japan, and recent knowledges about the relation of vector and rickettsia, and in the latter part, reviews the progressing studies on R. tsutsugamushi obtained in the author's laboratory, such as, the development of experimental technologies, rickettsial multiplication cycle in the host cell, discovery of various antigenic variants, chemical and antigenic structures of the rickettsia, and finally, mentions about the future problems on the disease and the rickettsia.
