Environmental Contamination of SARS-CoV-2 in a Non-Healthcare Setting Revealed by Sensitive Nested RT-PCR

Wong, J. C. C.; Hapuarachichi, H. C.; Arivalan, S.; Tien, W. P.; Koo, C.; Mailepessov, D.; Kong, M.; Nazeem, M.; Lim, M.; Ng, L. C.

Fomite-mediated transmission has been identified as a possible route for disease spread of the COVID-19 pandemic. In healthcare settings, evidence of environmental contamination by SARS-CoV-2 has been found in patients' rooms and toilets. Here, we investigate environmental contamination of SARS-CoV-2 in non-healthcare settings and assessed the efficacy of cleaning and disinfection in removing SARS-CoV-2 contamination. A total of 428 environmental swabs and six air samples was taken from accommodation rooms, toilets and elevators that have been used by COVID-19 cases. Through the use of a sensitive nested RT-PCR assay, we found two SARS-CoV-2 RNA positive samples from the room resided by a COVID-19 case, highlighting the risk of fomite-mediated transmission in non-healthcare settings and the importance of surface disinfection of spaces occupied by cases. Of note, we did not find evidence for air-borne transmission, nor of environmental contamination of elevators, which were transiently exposed to infected persons.