Dōgo Onsen Dōgo Onsen Dōgo Onsen is one of the oldest onsen hot springs in Japan, with a history stretching back over 1000 years. The springs are mentioned in the Man'yōshū (written c. 759) and, according to legend, Prince Shōtoku (574–622) used to partake of the waters. Dōgo Onsen was the favorite retreat of writer Natsume Sōseki (1867–1916) when he was working near Matsuyama as a teacher in what was at the time rural Shikoku. In Soseki's loosely autobiographical novel "Botchan", the eponymous main character is a frequent visitor to the springs, the only place he likes in the area. Dogo Onsen
Onsen found in some onsens with poor sanitation. Revelations of poor sanitary practices at some onsens have led to improved regulation by hot-spring communities to maintain their reputation. There have been reports of infectious disease found in hot bodies of water worldwide, such as various "Naegleria" species. While studies have found the presence of "Naegleria" in hot spring waters, the worrisome "Naegleria fowleri" amoeba has not been identified. Nevertheless, fewer than five cases have been seen historically in Japan, although not conclusively linked to onsen exposure. Many onsens display notices reminding anyone with open cuts, sores, or lesions not to bathe.