To explore the retention time and change pattern of the viral RNA of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant on the surfaces of different materials under different temperature, so as to provide a basis for the detection of SARS-CoV-2 on environmental samples and the formulation of relevant prevention and control strategies.

The deactivated throat swab samples of coronavirus disease 2019 (COVID-19) patients stored in the laboratory were selected and added on the surfaces of stainless steel, plastic, wood, cardboard and cotton cloth to get simulated pollution samples. The samples were placed at room temperature and 4℃. Three samples of each material were taken in batches and soaked on the 0 d, 1 d, 3 d, 7 d, 14 d and 30 d for nucleic acid extraction. Real-time RT-PCR was used to detect SARS-CoV-2 viral RNA. The recovery rates, detectable time and changes in Ct values of viral RNA on the surfaces of different materials after contamination were recorded and analyzed.

After contamination, the recovery rates were 1.75%-2.90% in cotton cloth, plastic and stainless steel, while those were much lower in wood and paperboard. On 30 d after contamination, all material surfaces were positive in SARS-CoV-2 RNA testing. The Ct values of viral RNA on the surface of stainless steel, wood, paperboard and cotton cloth increased rapidly in the first 7 days, and then changed slightly. The Ct values of viral RNA on the surface of plastic changed less comparing to the rest four materials.

After the virus contamination on the surface of materials, the viral nucleic acid maintained detective for 30 days with different degradation patterns. In routine environment surveillance, nucleic acid detection and other investigation methods should be integrated to comprehensively evaluation and determine the risk of virus transmission by contaminated goods.

Severe acute respiratory syndrome coronavirus 2; Nucleic acid detection; Environment surveillance; Nucleic acid residue