Use of FTA® card methodology for sampling and molecular characterization of Echinococcus granulosus sensu lato in Africa
Résumé
Cystic Echinococcosis is a parasitic disease caused by the cestode Echinococcus granulosus widely distributed in Africa. Monitoring of this parasite requires access to cyst samples on intermediate hosts observed at the slaughterhouse. In order to facilitate sampling in the field and analysis, the French National Reference Laboratory for Echinococcus spp. has developed a tissue derived from DNA sampling with FTA® card technology. The DNA samples were taken by applying the FTA® paper on the germinal layer after opening the cysts. The sampling technique was validated using frozen cysts (n = 76) stored in the laboratory and from field samples (n = 134) taken at the slaughterhouse by veterinarian technicians during meat inspection in Morocco, Mali and Mauritania. DNA was extracted after several weeks of storage at room temperature. PCR assays were performed using primers for generic cestode (cox1) and amplified fragments were sequenced. All samples taken in the lab and 80% of field samples were capable of molecular characterization. Cyst-derived DNA from FTA® samples can be useful for easy sampling, storage and rapid, safe and cheap shipment. The use of the FTA methodology will facilitate studies in the field to investigate the presence and genetic characterization of E. granulosus sensu lato in African countries.