Identification of Bulinus forskalii as a potential intermediate host of Schistosoma hæmatobium in Senegal

Understanding the transmission of Schistosoma hæmatobium in the Senegal River Delta requires knowledge of the snails serving as intermediate hosts. Accurate identification of both the snails and the infecting Schistosoma species is therefore essential. Cercarial emission tests and multi-locus (COX1 and ITS) genetic analysis were performed on Bulinus forskalii snails to confirm their susceptibility to S. hæmatobium infection. A total of 55 B. forskalii , adequately identified by MALDI-TOF mass spectrometry, were assessed. Cercarial shedding and RT-PCR assays detected13 (23.6%) and 17 (31.0%), respectively, B. forskalii snails parasitised by S. hæmatobium complex fluke. Nucleotide sequence analysis identified 6 (11.0%), using COX1, and 3 (5.5%), using ITS2, S. hæmatobium , and 3 (5.5%) S. bovis . This result is the first report of infection of B. forskalii by S. hæmatobium complex parasites.