わが国における回帰熱（再帰熱）は，明治28年（1895年）に日清戦争に従軍した兵士や軍夫が中国本土で罹患し，帰国後に広島の軍夫病院で発症が確認された症例が初発例であった。翌年の北島多一による神戸市と香川県における疫学調査により，多数の症例が確認され，その輸入感染症としての病態が明らかにされた。

その後，回帰熱は1897年制定の「伝染病予防法」の第1条第2項に規定する伝染病として取り扱われ，国立伝染病研究所（北里柴三郎所長）の主要な研究課題の一つとされており，多くの研究者による研究業績が残されている。

本総説においては，わが国における疫病から伝染病への推移，さらには感染症への変遷を辿り，回帰熱を巡る伝染病の法的規制の歴史を顧みることにより，今日の感染症教育に必要な“温故知新”を考察した。また，回帰熱は国内に定着した史実はなく，すべての症例が輸入感染症であることから，世界的な回帰熱の流行と研究の歴史に関わる情報を収集整理して記述した。

The first case of relapsing fever in Japan was reported in 1895, when a soldier or a military laborer who served in the Sino-Japanese War was infected with the disease in mainland China and later developed symptoms at a military hospital in Hiroshima after returning to Japan. The following year, epidemiological surveys conducted by Taichi Kitajima in Kobe City and Kagawa Prefecture confirmed a large number of cases and clarified the pathogenesis as an imported infectious disease.

Subsequently, relapsing fever was classified as a contagious disease as stipulated in Article 1, Paragraph 2 of the “Contagious Disease Prevention Law” enacted in 1897. This disease emerged as a primary focus of research and was one of the main research subjects of the National Institute of Contagious Diseases (Director Shibasaburo Kitasato), and numerous researchers have contributed to subsequent research achievements.

This review traces the classification transition from epidemic to contagious disease and then to infectious disease in Japan. It also examines the historical development of the legal regulations of contagious diseases surrounding relapsing fever. Furthermore, it considers the importance of “learning from the past, discovering new ideas” in the context of contemporary infectious disease education. Since there is no historical record of relapsing fever establishing itself in Japan and all cases are imported infections, a comprehensive review of information related to the history of relapsing fever epidemics worldwide, including research, was collected, organized, and described.