Rapid and sensitive on-site detection of SARS-CoV-2 RNA from environmental surfaces using portable laboratory devices

Abstract

Monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA on inanimate surfaces plays a crucial role in environmental surveillance, enabling the indirect detection of infected individuals and facilitating rapid infection control responses. However, developing a practical on-site, end-to-end method for detection remains a challenge. In this study, we established protocols for on-site detection of SARS-CoV-2 RNA on surfaces using two portable laboratory devices: The PicoGene PCR1100 and Bento Lab. Test particles comprised of inactivated viral particles containing partial sequences of SARS-CoV-2, type 1 poliovirus, coxsackie virus A16, and norovirus genogroups I and II were applied to reference materials as simulated contaminants. The direct detection method with the PicoGene PCR1100 achieved a recovery efficiency of 35.1% for the dried reference material. Furthermore, the Bento Lab, equipped with a microcentrifuge for on-site RNA purification, successfully detected a low concentration of inactivated SARS-CoV-2 reference standard. The recovery efficiency of the on-site RNA purification method on plastic, stainless steel, glass, and polyvinyl chloride surfaces ranged from 15.5% to 21.2%. Through the combination of these portable devices, SARS-CoV-2 RNA was detected within 1 h of swab sampling. This study contributes to the on-site risk assessment of infectious diseases by enabling the rapid detection of viral genomes. IMPORTANCE This study presents the development of a highly sensitive on-site method for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA on various surfaces, including doorknobs and tables. Identifying SARS-CoV-2 RNA on these surfaces can be crucial in guiding decision-making for implementing non-pharmaceutical interventions, such as zoning strategies, improving ventilation, maintaining physical distancing, and promoting increased hand hygiene practices. Moreover, the on-site detection system can facilitate the swift initiation of mitigation responses in non-laboratory settings, including long-term care facilities and schools. The protocols established in this study offer a comprehensive approach for achieving both sensitivity and rapidity in on-site SARS-CoV-2 RNA detection. Furthermore, since the RT-qPCR assay serves as the gold standard for detecting viral RNAs, the developed protocol holds potential for application to other viruses, including enteroviruses and noroviruses.