Development of multiplex cross displacement amplification combined with lateral flow biosensor assay for detection of virulent .

is the most common spp. in developed areas and the second most common in undeveloped regions. In this study, a multiple cross displacement amplification (MCDA) assay was used in combination with a lateral flow biosensor (LFB) assay to detect virulent strains containing the and genes. The multiplex MCDA-LFB assay detected at ≥1 pg/μL and at ≥10 fg/μL within 30 min in pure cultures maintained at 63°C. This assay was sensitive for ~37 CFU of virulent and ~3.7 CFU of spp. and enteroinvasive in stimulated fecal samples and had 100% specificity among 59 reference strains. The MCDA-LFB assay was also able to differentiate between virulent and other spp. and enteroinvasive among 99 clinical isolates. In summary, a multiplex MCDA-LFB assay was developed for rapid, convenient, point-of-care, and accurate identification of virulent within 30 min and at a constant temperature without the need for expensive lab equipment.