Experimental Compatibility of Bulinus truncatus Populations with Schistosoma haematobium in Cameroon

Author(s): Mohamed Bagayan, Alvine Christelle Kengne-Fokam, Hugues Clotaire Nana-Djeunga, Hermann Sorgho, Dramane Zongo, Flobert Njiokou

Purpose: The present study was initiated to estimate the risk of Schistosoma haematobium expansion by assessing the susceptibility of Bulinus truncatus populations to Schistosoma haematobium.

 Methods: Bulinus truncatus snails were harvested from three Cameroonian localities (Loum, Mbafam, Kekem) and one situated in Burkina Faso (Yamtenga). Once G1 samples constituted, they were divided into exposed and control groups and infested with two S. haematobium strains (Loum and Barombi-Kotto). The prepatent period, infection success rate and cercarial chronobiology were studied. Effects of S. haematobium infection on snail oviposition and mortality rates were also investigated.

Results: Results showed that all Cameroonian Bulinus truncatus populations were susceptible to S. haematobium. Their infection success rates varied from 75.5% to 6.3% between sympatric and allopatric couples (p<0.05). The shortest prepatent period was found in an allopatric couple (26.90 days). The mortality rate varied among populations, it was different between exposed and control snail groups in Loum (p=0.001) while it was similar in Mbafam (p=0.423).

Conclusion: Epidemiologically, these susceptible Bulinus populations could induce a reappearance and/or an increase of the urinary schistosomiasis prevalence in Cameroon.