SARS-CoV-2 RNA contamination of inanimate surfaces and virus viability in a health care emergency unit

Colaneri, Marta; Seminari, Elena; Novati, Stefano; Asperges, Erika; Biscarini, Simona; Piralla, Antonio; Percivalle, Elena; Cassaniti, Irene; Baldanti, Fausto; Bruno, Raffaele; Mondelli, Mario U.

OBJECTIVES: To detect possible SARS-CoV-2 RNA contamination of inanimate surfaces in areas at high risk of aerosol formation by patients with COVID-19. METHODS: Sampling was performed in the emergency unit and the sub-intensive care ward. SARS-CoV-2 RNA was extracted from swabbed surfaces and objects and subjected to real-time reverse transcriptase–polymerase chain reaction (RT-PCR) targeting RNA-dependent RNA polymerase and E genes. Virus isolation from positive samples was attempted in vitro on Vero E6 cells. RESULTS: Twenty-six samples were collected and only two were positive for low-level SARS-CoV-2 RNA, both collected on the external surface of Continuous Positive Airway Pressure (CPAP) helmets. All transport media were inoculated onto susceptible cells, however, none induced a cytopathic effect on day 7 of culture. CONCLUSIONS: Even though daily contact with inanimate surfaces and patient fomites in contaminated areas may be a medium of infection, our data obtained in real life conditions suggest that it might be less extensive than hitherto recognized.