A case of human infection with Diphyllobothrium in Fukuyama City, Hiroshima Prefecture

Three strobilae with scoleces were expelled from a 16-year-old man by the administration of 600mg (20mg/kg) praziquantel. The No.1 strobila had a scolex 6.5cm in length. The No.2 strobila had a scolex 28cm in length. The No.3 strobila with a scolex and mature segments was 142cm in length. The No.3 strobila was identified as Diphyllobothrium latum by its morphological characteristics. The No.1 strobila had a scolex similar to that of the No.3 strobila. However, the No.2 strobila was equipped with a hammer-like scolex. This result suggests that the No.2 strobila belonged to species other than D. Latum.