In a new research paper, titled “Severe acute respiratory syndrome coronavirus 2 RNA contamination of inanimate surfaces and virus viability in a health care emergency unit” (published in Clinical Microbiology and Infection), virologists have looked at patterns relating to the presence of viral RNA in the healthcare setting. The study looks at the recovery of viral RNA, although tests for viability were not conducted.
The virologists took a series of samples, to examine for the presence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA, from various inanimate surfaces. The locations selected were areas that were potentially subject to a high risk of aerosol formation by patients with coronavirus disease 2019 (COVID-19). Earlier studies have shown how the virus is recoverable from surfaces like plastic, stainless steel, copper, and cardboard.
The samples were taken within an emergency unit and from a an intensive care ward. After the swabs had been taken from different surface materials, any SARS-CoV-2 RNA was then extracted from each swab and a real-time RT-PCR targeting RNA-dependent RNA polymerase and E genes assay was run. After this, virus isolation from positive samples was attempted in vitro on Vero E6 cells (a lineage of cells used in cell cultures).
The analysis of the data found that of 26 samples taken, just two were positive for the virus. With the positive samples, only low-level SARS-CoV-2 RNA was detected. Both positive samples were from the same items, these were isolated from the external surface of continuous positive airway pressure helmets.
From this study, the relative risk of coronavirus from surfaces was assessed as relatively low. This is in contrast to what has been established for viral recovery from aerosols. It remains prudent to consider the risks from daily contact with inanimate surfaces, but such real-life data indicates that the possibility of contamination could be less extensive than some earlier studies have alluded.
