SARS-CoV-2 surveillance with environmental surface sampling in public areas

Abstract

Contaminated surfaces are one of the ways that coronavirus disease 2019 (COVID-19) may be transmitted. SARS-CoV-2 can be detected on environmental surfaces; however, few environmental sampling studies have been conducted in nonclinical settings. The objective of this study was to detect SARS-CoV-2 RNA on environmental surfaces in public areas in Las Vegas, Nevada. In total, 300 surface samples were collected from high-touch surfaces from high-congregate public locations and from a public health facility (PHF) that was visited by COVID-19 patients. Environmental samples were analyzed with quantitative reverse-transcriptase polymerase chain reaction (RT-qPCR) using SARS-CoV-2 specific primers and probes for three target genes. Results showed that 31 out of 300 (10.3%) surface samples tested positive for SARS-CoV-2, 24 at the PHF and 7 in high-congregate public locations. Concentrations ranged from 102 to 106 viral particles per 3 ml sample on a wide variety of materials. The data also showed that the N gene assay had greater sensitivity compared to the S and ORF gene assays. Besides frequently touched surfaces, SARS-CoV-2 was detected in restrooms, on floors and surfaces in contact with floors, as well as in a mop water sample. The results of this study describe the extent and distribution of environmental SARS-CoV-2 contamination in public areas in Las Vegas, Nevada. A method using the N gene PCR assay was developed for SARS-CoV-2 environmental monitoring in public areas. Environmental monitoring with this method can determine the specific sites of surface contamination in the community and may be beneficial for prevention of COVID-19 indirect transmission, and evaluation and improvement of infection control practices in public areas, public health facilities, universities, and businesses.

A 17-month longitudinal environmental sampling study carried out on public transport vehicles operating in England during the COVID-19 pandemic identified low levels of SARS-CoV-2 RNA contamination

“…Appropriate mitigation strategies should be identified and implemented, particularly during times of high community transmission. However, we found no evidence of public transport contamination with SARS-CoV-2 RNA being higher in comparison to other public spaces including university campuses, public squares, business premises and bus stations (Abrahão et al, 2021; Cardinale et al, 2022; Harvey et al, 2021; Mihajlovski et al, 2022; Zhang et al, 2022).…”

Exploring indoor and outdoor dust as a potential tool for detection and monitoring of COVID-19 transmission

“…These findings suggest that measuring viral concentrations in dust can serve as an indicator to assess the risk of COVID-19 transmission, which is consistent with prior research. 14 , 34 Furthermore, the presence of higher viral concentrations in the dust could indicate a greater likelihood of COVID-19 incidence in the community.…”

Environmental surface monitoring as a noninvasive method for SARS-CoV-2 surveillance in community settings: Lessons from a university campus study

“…We employed qRT-PCR to identify SARS-CoV-2 RNA on high-touch environmental surface samples which provide semi-quantitative information on the viral gene copy present in the environmental surface. This method has been used in other studies to quantify viral gene copy on environmental surface (Mihajlovski et al, 2022;Zhang et al, 2022). However, these data should be interpreted carefully when collecting environmental surface samples from a community setting (Han et al, 2021).…”