Ultrafast visual detection of Streptococcus suis via HtpsC ‐targeted LAMP – CRISPR –Cas12a coupled with lateral flow immunochromatography

This study describes a rapid, visual detection platform for Streptococcus suis , a significant zoonotic pathogen, by integrating loop‐mediated isothermal amplification (LAMP) with CRISPR–Cas12a and a lateral flow immunochromatographic strip (LFIA) readout. Targeting the conserved HtpsC gene, specific LAMP primers and a PAM‐compliant CrRNA were designed. Following isothermal amplification, the Cas12a/CrRNA complex recognizes the HtpsC amplicon, initiating target‐specific cleavage and subsequent trans‐cleavage of a dual‐labeled ssDNA reporter (FAM‐BIO), enabling visual detection on a LFIA; a design which reduces false positives. The optimized assay detected HtpsC‐positive S. suis strains within 45 min and achieved a visual detection limit of 1.1 × 10 2 CFU/mL under laboratory conditions, with no cross‐reactivity observed against the tested nontarget bacteria. In addition to pure‐culture dilutions, the assay was further evaluated using spiked porcine blood samples and achieved similar detection performance, supporting its preliminary applicability in a complex biological matrix. Overall, this study provides an HtpsC‐targeted visual detection workflow for screening of S. suis and is expected to be further applied to on‐site rapid detection of clinical samples.