Rapid visual detection of Giardia duodenalis in faecal samples using an RPA-CRISPR/Cas12a system

Parasitol Res. 2024 Apr 4;123(4):176. doi: 10.1007/s00436-024-08197-y.

Abstract

Giardiasis is a common intestinal infection caused by Giardia duodenalis, which is a major economic and health burden for humans and livestock. Currently, a convenient and effective detection method is urgently needed. CRISPR/Cas12a-based diagnostic methods have been widely used for nucleic acid-based detection of pathogens due to their high efficiency and sensitivity. In this study, a technique combining CRISPR/Cas12a and RPA was established that allows the detection of G. duodenalis in faecal samples by the naked eye with high sensitivity (10-1 copies/μL) and specificity (no cross-reactivity with nine common pathogens). In clinical evaluations, the RPA-CRISPR/Cas12a-based detection assay detected Giardia positivity in 2% (1/50) of human faecal samples and 47% (33/70) of cattle faecal samples, respectively, which was consistent with the results of nested PCR. Our study demonstrated that the RPA-CRISPR/Cas12a technique for G. duodenalis is stable, efficient, sensitive, specific and has low equipment requirements. This technique offers new opportunities for on-site detection in remote and poor areas.

Keywords: Giardia duodenalis; Lateral flow strips; RPA-CRISPR/Cas12a; Recombinase polymerase amplification; Visual detection.

MeSH terms

  • Animals
  • Biological Assay
  • CRISPR-Cas Systems
  • Cattle
  • Giardia / genetics
  • Giardia lamblia* / genetics
  • Giardiasis* / diagnosis
  • Giardiasis* / veterinary
  • Humans