Physa marmorata (Mollusca: Physidae) as a natural intermediate host of Trichobilharzia (Trematoda: Schistosomatidae), a potential causative agent of avian cercarial dermatitis in Brazil

• Published in: Acta tropica 2014-10, Vol.138, p.38-43
• Main Authors: Pinto, Hudson A., Brant, Sara V., de Melo, Alan L.
• Format: Article
• Language: English
• Subjects: Acanthaceae - parasitology; Animals; Brazil; Cercariae; Cluster Analysis; DNA, Helminth - chemistry; DNA, Helminth - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; DNA, Ribosomal Spacer - chemistry; DNA, Ribosomal Spacer - genetics; Microscopy; Molecular Sequence Data; Phylogeny; Physa; RNA, Ribosomal, 28S - genetics; Schistosomatidae - anatomy & histology; Schistosomatidae - genetics; Schistosomatidae - isolation & purification; Schistosomes; Sequence Analysis, DNA; Trichobilharzia
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2014.06.002

A morphological and molecular study of cercariae of Trichobilharzia found in molluscs from Brazil is presented for the first time. •Physa marmorata is an intermediate host of Trichobilharzia in Brazil.•A morphological and molecular comparison with congeners species is presented.•This is the first molecular study of a South America species of Trichobilharzia.•The potential role of Trichobilharzia in outbreaks of cercarial dermatitis in Brazil is discussed. Species of Trichobilharzia are the main etiological agents of cercarial dermatitis in humans, which is considered a re-emerging disease. Despite the diversity and global distribution of species of this genus, studies of Trichobilharzia are scarce in South America. The goal of our investigations is better understand the diversity, distribution and life cycle of avian schistosomes and their likely role in causing dermatitis in Brazil. As part of this effort, cercariae found in naturally infected Physa marmorata were identified by morphological and molecular (mitochondrial cox1, nuclear ITS1 and 28S gene regions) methods as Trichobilharzia sp. These cercariae are similar morphologically to T. jequitibaensis described previously from Brazil and similar genetically to the North American physid transmitted species T. querquedulae and T. physellae. This is the first report of a potential agent of cercarial dermatitis from naturally infected snails from Brazil and first molecular characterization of a South American species of Trichobilharzia. A discussion follows concerning the potential role of this species has in outbreaks of dermatitis in Brazil.