a parasite called 'Japanese blood fluke' (Oncomelania nosophora) whose intermediate host is a snail
日本住血吸虫病という病気 - EDR日英対訳辞書
It is also said that his death was caused by a decline inhis physical health resulting from schistosomiasis japonica (form of bilharzia caused by the Oriental bloodfluke Schistosoma japonicum) which became epidemic as a local disease in modern times
また、近代には地方病として蔓延した日本住血吸虫病による体力の低下という説もある。 - Wikipedia日英京都関連文書対訳コーパス