Detection of SARS-CoV-2 RNA on contact surfaces within shared sanitation facilities

Abstract

Contamination of contact surfaces with SARS-CoV-2 has been reported as a potential route for the transmission of COVID-19. This could be a major issue in developing countries where access to basic sanitation is poor, leading to the sharing of toilet facilities. In this study, we report SARS-CoV-2 contamination of key contact surfaces in shared toilets and the probabilistic risks of COVID-19 infections based on detection and quantification of the nucleic acid on the surfaces. We observed that 54–69% of the contact surfaces were contaminated, with SARS-CoV-2 loads ranging from 28.1 to 132.7 gene copies per cm 2 . Toilet seats had the highest contamination, which could be attributed to shedding of the virus in feces and urine. We observed a significant reduction in viral loads on the contaminated surfaces after cleaning, showing the potential of effective cleaning on the reduction of contamination. The pattern of contamination indicates that the most contaminated surfaces are those that are either commonly touched by users of the shared toilets or easily contaminated with feces and urine. These surfaces were the toilet seats, cistern handles and tap handles. The likelihood (probability) of infection with COVID-19 on these surfaces was highest on the toilet seat (1.76 × 10 −4 (1.58 × 10 −6 )) for one time use of the toilet. These findings highlight the potential risks for COVID-19 infections in the event that intact infectious viral particles are deposited on these contact surfaces. Therefore, this study shows that shared toilet facilities in densely populated areas could lead to an increase in risks of COVID-19 infections. This calls for the implementation of risk reduction measures, such as regular washing of hands with soap, strict adherence to wearing face masks, and effective and regular cleaning of shared facilities.

Utilization of SARS-CoV-2 Wastewater Surveillance in Africa—A Rapid Review

“…These articles were imported into Convidence and nine duplicates were removed, leaving 35 articles included in the abstract screening. A total of 23 studies were excluded following abstract screening, leaving 12 articles [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ] for full-text screening. Four articles [ 27 , 28 , 30 , 34 ] were excluded after full-article screening, leaving eight articles for data extraction ( Supplementary Table S1 ).…”

“…A total of 23 studies were excluded following abstract screening, leaving 12 articles [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ] for full-text screening. Four articles [ 27 , 28 , 30 , 34 ] were excluded after full-article screening, leaving eight articles for data extraction ( Supplementary Table S1 ). Of the excluded articles, two were commentaries [ 30 , 34 ], and one did not report on the utilization of SARS-CoV-2 wastewater surveillance [ 27 , 28 ].…”

“…Four articles [ 27 , 28 , 30 , 34 ] were excluded after full-article screening, leaving eight articles for data extraction ( Supplementary Table S1 ). Of the excluded articles, two were commentaries [ 30 , 34 ], and one did not report on the utilization of SARS-CoV-2 wastewater surveillance [ 27 , 28 ]. More details are presented in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart in Figure 1 .…”

Longitudinal, virological, and serological assessment of hospitalized COVID-19 patients

“…Particular attention should be paid in healthcare settings, where COVID-19 patients are forced to share the facilities or to stay in the bed constantly, without the possibility of using the bathroom, but with the continuous use of diapers. The repeated use of shared toilets, together with the infrequent cleaning, might result in progressive accumulation of virus, on the toilet seats, sink, and door handle (Amoah et al 2021 ; Chia et al 2020 ; Ding et al 2021 ; Li et al 2020b ; Ong et al 2020 ), where the virus may persist for up to 4 days (Chin et al 2020 ). Additionally, the risk of SARS-CoV-2 fecal contamination may be much higher in poor-setting countries, characterized by poor sanitation (Jones et al 2020 ).…”

Can SARS-CoV-2 be transmitted via faeces?

“…As the presence of SARS-CoV-2 genetic material and live virus in patients’ faeces became apparent, apprehension increased as COVID-19 patients can also present gastrointestinal symptoms such as diarrhoea [ 3 – 9 , 17 ▪▪ ]. The occurrence of loose stools in COVID-19 patients extends the risk of environmental contamination of toilets and contact surfaces through aerosols or faecal matter deposition [ 23 ]. Facilities in areas shared by individuals more susceptible to severe illness such as wards or care homes are of particular concern, as patients are deemed virus-free upon negative nasopharyngeal tests, even though the presence of virus in the intestine can outlast its presence in the respiratory tract [ 10 ▪ , 14 ▪ , 19 , 21 ].…”