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

Abstract

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.

Outbreak of swimmer's itch in Central Italy: Description, causative agent and preventive measures

“…At present, in Europe, foci of swimmer's itch have been reported from Czech Republic (Kolářová, Horák, & Sitko, ), Switzerland (Chamot, Toscani, & Rougemont, ), Poland (Zbikowska, ), France (Jouet et al, ), the Netherlands (Schets, Lodder, Duynhoven, & Roda Husman, ), England (Lawton et al, ), Germany (Selbach et al, ) and Belgium (Caron et al, ). In Italy, it was first reported in the lake of Garda (northern Italy) in 1998 (Golo et al, ) and, more recently, in central Italy in the lake of Vico, where Cipriani et al () identified the species T. franki as the causative agent of the dermatitis and R. auricularia as its intermediate host. At present, these are the only reports of cercarial dermatitis from our country.…”

“…As man is an accidental host of these parasites, cercariae (furcocercariae) are not able to mature in humans and usually are killed in derma. In Europe, as well as in most of temperate latitudes, the most important agents of swimmer itch belong to the genus Trichobilharzia (Horák et al, ), namely the four species Trichobilharzia franki , Trichobilharzia szidati , Trichobilharzia regenti and Trichobilharzia salmanticencis (Cipriani, Mattiucci, Paletti, Scialanca, & Nascetti, ; Soldánová et al, ). Trichobilharzia spp.…”

Two Cases of Cercarial Dermatitis in An Italian Lake

“…To date, little is known of the prevalence of dermatitis caused by Trichobilharzia spp, because of both a lack of coordination between epidemiological studies and analysis of parasite-fauna of fresh water, and of the absence of previous diffusion of this dermatitis in Central Europe. The highest diffusion has been reported in Northern Europe and in Central and Eastern United States (1,3,4).…”

“…Lake Vico, located in the Tuscia province of Central Italy, is of volcanic origin and is . frequented in the summer period by several bathers, and several cases have been reported in literature of skin eruptions accompanied by intense itching caused by Trichobilharzia spp after bathing in this lake (1).…”

“…Cercarial dermatitis (also named Swimmer's itch or Clam-digger's disease) was first described by LaValette et al in 1885, but today its impact is increasing and it is considered an emerging disease (1,2). To date, little is known of the prevalence of dermatitis caused by Trichobilharzia spp, because of both a lack of coordination between epidemiological studies and analysis of parasite-fauna of fresh water, and of the absence of previous diffusion of this dermatitis in Central Europe.…”