Liu, Xu, Cao and team developed a CRISPR‑based diagnostic that detects BK and JC polyomaviruses in post‑kidney transplant patients. The assay combines sequence‑specific CRISPR detection with rapid amplification to identify viral DNA at low copy number, enabling earlier identification of reactivation events that threaten graft function. The platform promises faster, point‑of‑care‑adaptable surveillance compared with standard PCR, with potential to reduce graft loss by informing preemptive antiviral or immunosuppression adjustments.