Primer design and positive control plasmids
The 18S ribosomal RNA sequence (18S rRNA) of S. japonicum (FJ176682) and S. mekongi (U89871) were selected and used to differentiate the 2 species. The PCR primers (Schis_F; 5´-GAC TTT CGG GTT GCC TGA TC -3´ and Schis_R; -5´- ACC GGA TCG CTT CAA CAG T-3´) were designed to amplify a particularly variable region [24].