Molecular evidence of Trichobilharzia franki Müller and Kimmig, 1994 (Digenea: Schistosomatidae) in Radix auricularia from Central Italy.

The molecular approach was used to identify the first focus of human cercarial dermatitis occurring during the spring-summer season in Vico Lake, a Natural Reserve Area in Central Italy. Sequences of 586 bp length of the partial region of 18S and ITS-1 ribosomal DNA from cercariae were obtained. They were compared with extant GenBank sequences of Trichobilharzia. Accordingly, the ocellate furcocercariae were identified as belonging to the species Trichobilharzia franki Müller and Kimmig, 1994. Sequences of the 18S (712 bp) and ITS-2 (218 bp) rDNA gene of snails belonging to the family Lymnaeidae collected in the study area have allowed detection of this bird schistosome in Italy in Radix auricularia. The prevalence of the schistosome infection in snails was P = 9.6%. The reduction in habitat disturbance at the lake, as a result of its recent dedication as a nature reserve, has enhanced bird species abundance and richness. This has favoured the establishment of the life cycle of T. franki in the study area.