Rapid development and field evaluation of a portable CRISPR-based assay for Mpox during the 2025 Sierra Leone outbreak

Abstract In early 2025, Sierra Leone experienced a large outbreak of mpox clade IIb, underscoring the urgent need for portable, low-cost diagnostics in decentralized settings. We rapidly developed and field-deployed Mpox SHINE, a CRISPR–Cas13 assay that integrates lyophilized reagents, ambient-temperature lysis, and automated fluorescence detection on a portable device, the DxHub. The assay achieved analytical sensitivity down to 10 copies/µL with minimal hands-on time. In-country evaluation of 56 clinical specimens showed complete concordance with qPCR, with 100% sensitivity (45/45) and 100% specificity (11/11) at the sample level. Mpox SHINE also detected the virus directly from unextracted lesion swabs, maintaining 100% sensitivity and specificity in 16 samples (8 positive, 8 negative). Across extracted and unextracted samples, the mean time-to-result was ∼35 minutes, with all positives detected within 45 minutes. Thus, Mpox SHINE performed on the DxHub demonstrates how CRISPR-based pathogen detection can be rapidly translated into portable tools for the front lines of outbreak response. Teaser CRISPR-Cas13 assay and portable device bring rapid, reliable mpox testing to outbreak settings.