A rapid visual detection method for Schistosoma japonicum in Oncomelania hupensis snails using recombinase-aided amplification and lateral flow dipsticks.

BACKGROUND

Effective surveillance of infected Oncomelania hupensis snails is pivotal for schistosomiasis elimination, yet traditional methods lack sensitivity and molecular assays require sophisticated equipment.

METHODS

We developed an RAA-LFD method targeting the SjG28 gene, using biotin-labeled primers and FAM-labeled probes, with isothermal amplification at 39°C for 15 min and visual readout on dipsticks.

RESULTS

The assay achieved a detection limit of 1 pg/μL genomic DNA and 10 copies/μL plasmid DNA, with no cross-reactivity against six other parasites. It detected as few as one infected snail among 50 and identified infections from day 7 post-infection.

CONCLUSION

This equipment-free, visual RAA-LFD method offers a practical solution for field-based surveillance, with potential to strengthen schistosomiasis elimination efforts in resource-limited settings.