What is the risk of acquiring SARS-CoV-2 from the use of public toilets?

Abstract

Public toilets may act as a contact hub point for SARS-CoV-2 transmission. • All accepted transmission mechanisms for SARS-CoV-2 co-exist in a public toilet. • Faecal and urinary derived aerosols contain viable SARS-CoV-2 virus. • Issues over space, ventilation, frequency of use, cleaning and maintenance compound the transmission risk. • Actions to prevent COVID-19 infection are offered in lieu of supportive scientific evidence.

Importance of the Precautionary Principle With Regard to the Risk of Exposure to Aerosols Containing Viral Loads of SARS-CoV-2 Present in Feces: In Perspective

“…The originality of this article comes from the fact that it combines the results of different works relating to the characterization of the emissions produced when we flush the toilet, the number of times we have to flush the toilet to significantly reduce the risk of infection as well as the variation in the concentration of the virus in the air as a function of time. Combination of these information linked to the results of work carried out more recently by various researchers ( 19 , 20 , 37 , 38 ) which demonstrated the presence of SARS-COV-2 in emissions from toilets clearly indicates that the risk of exposure to aerosols contaminated by SARS-COV-2 can persist for some time, even in the absence of contaminated stools in the toilet.…”

“…This threat is believed to come from the creation of droplets and aerosols laden with SARS-CoV-2 virus when the toilet is flushed. There is therefore a risk of possible exposure by aerosol for the general population in public toilets ( 19 , 20 ) as well as the healthcare workers caring for patients with COVID-19 Despite the context of the pandemic, this risk of contamination for health personnel is not generally considered by public health authorities because it is not a proven risk, which would require the implementation of preventive procedures. Although this contamination risk has not yet been proven, the various studies carried out so far tend to show that this path presents a plausible danger of contamination.…”

Effect of Relative Humidity on Transfer of Aerosol-Deposited Artificial and Human Saliva from Surfaces to Artificial Finger-Pads

“…The way that the time elapsed between inoculation of the surface and contact interacts with environment conditions suggests that, e.g., frequently contacted surfaces may pose a risk of fomite exposure regardless of environmental conditions, whereas the risk associated with less frequently contacted surfaces is dependent on a combination of both temperature and RH, with risks likely to be persisting longer in more humid environments and at temperatures commonly experienced in indoor settings. Such higher humidity conditions may be more likely to be found in bathroom environments, and several studies have shown that higher levels of contamination have been found in toilets and bathrooms [ 55 ]. Greatest risk would be anticipated to be the initial contact events prior to dilution effects, as subsequent touches redistribute the viral load.…”

Airborne SARS-CoV-2

“…SARS-CoV-2 survives in faeces, urine, and waste water, and aerosol transmission through interconnected sanitary drains (just as for SARS-1) needs further exploration 17. Viral spread in toilet facilities might not feature in the literature, but that does not mean the risk should be ignored.…”

“…Viral spread in toilet facilities might not feature in the literature, but that does not mean the risk should be ignored. Faecal aerosols might have played an important role in transmission during the covid-19 pandemic, especially as diarrhoea is common among infected patients and viral shedding persists in stool despite negative respiratory sample results 1718…”