Development of a Platform for in-situ Airborne Virus Detection by Interfacing RT-LAMP Assay with a Condensational...

Collection and identification of airborne viruses conventionally involve two separate processes: air sampling in the field and subsequent laboratory-based detection and analyses. They are time-consuming, which delays early warnings and hinders timely implementation of public health countermeasures. In-situ virus detection methods that enable preliminary identification at the sampling site can improve timeliness, eliminating the need for sample transport and allowing rapid decision-making. Herein, we developed and evaluated an integrated system that connects a water condensation-based aerosol collector called VIVAS with an in-situ detection platform known as VLEAD. We designed and fabricated an interface to serve both as the VIVAS' collection chamber and as a conduit for fluid transfer into the VLEAD. The design achieved over 90% collection efficiency for particles ≥3 μm after computational fluid dynamics simulation optimization, and experimental testing confirmed a physical collection efficiency of approximately 95%. When exposed to lab-generated aerosols containing human coronavirus OC43 (HCoV-OC43), the system achieved a 100% detection rate for samples containing > 10³ genome equivalents (GE) of virus per sample (4-5 GE/μL, triplicates), verified by RT-qPCR. The integrated system replaced the standard Petri dish in the commercially available VIVAS and enabled seamless transfer for RT-LAMP-based detection. The limit of detection was comparable to the level at which viruses such as SARS-CoV-2 have been collected using the VIVAS during environmental sampling reported in other studies. That performance demonstrated strong potential for rapid, in-situ detection of airborne coronaviruses and potentially other viruses in field settings or public spaces during respiratory viral disease outbreaks.