Dibothriocephalus nihonkaiensis and dibothriocephalosis nihonkaiensis

Abstract

Since the 1880s, most Japanese fish tapeworms and Diphyllobothrium latum (later renamed Dibothriocephalus latus) distributed in Europe were considered to be the same species. However, comparative studies of the two led to a 1986 report identifying the Japanese fish tapeworm as a distinct species from D. latum, and it was named Diphyllobothrium nihonkaiense (later renamed Dibothriocephalus nihonkaiensis). The second intermediate host of D. nihonkaiensis is fish of the genus Oncorynchus, but the first intermediate host remains unknown. In recent years, diagnosis of this tapeworm infection has shifted to genetic testing. Symptoms and signs of human dibothriocephalosis nihonkaiensis are mild, and praziquantel is effective.