The spread of the SARS-CoV-2 virus caused a global health emergency and severe damage on societies, especially in least developed, fragile and crisis affected countries. In response to the pandemic, access to safe water, sanitation and hygiene is vital to minimise virus transmission, maintain public health and to assure functioning medical service.
SARS-CoV-2 viruses are mainly transmitted via droplets and aerosols through e.g. exhaling or coughs and sneezes (the latter with a higher transmission risk). Transmission routes are :
So far, there is no evidence that the virus is spreading via water. This has been confirmed by the WHO . Some coronaviruses can potentially survive in the gastrointestinal tract and be spread by the faecal-oral route via contaminated surfaces or via inhalation of contaminated wastewater droplets and aerosols.  However, the infection risk from faecal matter, faecal sludge or raw wastewater is considered to be low.
The overarching recommendations of WHO and UNICEF on COVID-19 prevention and mitigation that WASH actors should follow can be summarised as follows :
To prevent the virus transmission, it is important to ensure access to a minimum daily volume of drinking water, to basic household sanitation and enhance safe hygiene behaviour for all. A quarter of the world’s population lacks access to a reliable water supply and over half lack access to safely managed sanitation. In the least-developed countries, about 22 percent of healthcare facilities lack access to improved water and improved sanitation services.
But not only the access deficits need to be addressed in the WASH response. Stronger emphasis than ever needs to be put on all recipients of WASH services (people and institutions), securing the continuity and affordability of products and services . This means that also humanitarian actors may need to focus more strongly on supporting local markets or utilities running supply systems to prevent them from further deterioration.
Safely managed water and sanitation services, good hygiene practice and waste management creates substantial benefits not only by supporting the prevention of COVID-19 and other infectious diseases  but also by improving people’s livelihood, education, safety, dignity and equity in times of a severe social crisis.
Special precautions are required in situations and sanitation facilities with high infection risks. These include health care facilities, situations where shared sanitation facilities are used as in schools, public buildings, informal/high-density settlements or refugee and IDP camps. Similar can apply to densely populated low-income communities and emergencies situations. All points mentioned above apply especially in these high-risk conditions. Additional points are summarised below.
In health-care and in other shared sanitation facilities physical distancing between users and hand washing with soap must be ensured. Soap and water or an alcohol-based hand sanitiser that contains at least 60% alcohol must be provided. If soap is in short supply, soapy water may be an alternative (or a 0.05% chlorine solution if chlorine is sufficiently available and does not compete with other uses such as drinking water disinfection. Note that soap and 0.05% chlorine solution should not be used together). People, who are infected or suspected to be infected should be provided with their own toilets. The obligatory use of an appropriate mouth-nose masks inside of the facility is recommended. A regular ventilation and effective circulation with fresh air can significantly reduce the risk of infection through aerosols . Flush toilets should be flushed with the lid down to prevent droplet splatter and aerosol clouds . Cleanliness of shared facilities need to be maintained strictly . This includes at least daily disinfection of sanitation facilities (toilets, bathrooms, showers) with detergents with 70% ethanol and/or 0.5% sodium hypochlorite and even more frequent cleaning of frequently touched surfaces. Personal Protective Equipment (PPE), ideally disposable gloves, disposable gown, FFP2/N95/KN95 mask and safety goggles must be worn when handling potentially infective material. Workers should be properly trained in how to put on, remove and how to dispose PPE.
If health-care facility toilets are not connected to sewers, hygienic on-site containment and treatment systems should be ensured such as pit latrines and septic tanks. When pits or tanks are full, sludge needs to be transported for off-site treatment or treated on-site where space and soil conditions permit. For unlined pits, regular precautions should be taken to prevent contamination of the environment (minimum distance of 1.5m between the bottom of the pit and the groundwater table; at least 30 m horizontally from any groundwater source). There is no reason to empty latrine pits and holding tanks of excreta from suspected or confirmed COVID-19 cases unless they are at capacity. Untreated faecal sludge and wastewater from health facilities should never be released on land used for food production, aquaculture or disposed of in recreational waters. 
The risk of being infected is rather limited if people working along the entire sanitation service chain or with contaminated matter follow occupational safety regulations and use the recommended PPE . The risks from contaminated surfaces (e.g. in shared sanitation facilities) can substantially be reduced by cleaning and disinfection, with e.g. 0,5% sodium hypochlorite solution or 70 % ethyl alcohol .
Detecting of SARS-CoV-2 or its RNA fragments in wastewater and sludge may complement public health data and provide, for example, information on when cases may increase a few days in advance of such peaks being detected by the responsible health institutions . For further details refer to .
To enable effective hygiene practices to prevent transmission of the SARS-CoV-2 virus, it is important to ensure access to safe drinking water, sufficiently available for drinking, frequent handwashing, personal hygiene and cleaning practices in households as well as in institutions (e.g. schools, health care facilities) and shared facilities in informal/high-density settlements or refugee/IDP camps. As always in WASH emergency response a Free Residual Chlorine (FRC) of ≥0.2–0.5mg/l after at least 30 minutes contact time should be maintained. All storage tanks and containers must be regularly cleaned .
In places where a safe water supply is not available; household water treatment technologies and practices are effective. These include among others: Boiling (H.9), Membrane Filteration (H.4), Solar Disinfection (H.12) and, in non-turbid waters, Ultraviolet (UV) Irradiation (H.11) and appropriately dosed Chlorination (H.6 and H.7).
The quality of water used for handwashing does not need to meet drinking-water standards. Evidence suggests that even water with moderate faecal contamination when used with soap and the correct technique and a higher frequency can be effective in removing pathogens from hands .
At shared WASH facilities (e.g. water points) social distancing measures need to be applied, so that services can be accessed safely . This includes effective communication of the importance of social distancing when using communal services and marking social distance intervals on/near facilities. Queuing times can be reduced by increasing operation times, installing additional temporary facilities. Regular disinfection of common contact surfaces (e.g. door handles and taps) with 0.5% chlorine solution needs to be ensured. For indoor facilities the obligatory use of an appropriate mouth-nose masks is recommended. A regular ventilation and effective circulation with fresh air can significantly reduce the risk of infection through aerosols inside of shared facilities .
No evidence that the COVID-19 virus is found in drinking-water, surface waters or groundwater. No additional measures for the operation of safe water supply systems, beside the ones described in the existing WHO guidelines on the safe management of drinking water and sanitation need to be applied.
Water services should not be cut off because of consumers’ inability to pay, and governments should prioritise providing access to people without access to water services, through other immediate actions such as Protected Boreholes (I.8), Water Trucking (D.3), or extending piped supplies (D.7 and D.8) . Individuals and organisations involved in providing water, sanitation and hygiene services should be designated as providing essential services and be allowed to continue their work during movement restrictions .
Due to the lock-down many premises may experience low or no water flow over a longer period (e.g. in schools). This may result in water stagnation and an associated deterioration of water quality (e.g. survival or regrowth of microbial pathogens due to chlorine decay and leaching of harmful metals from pipework). To minimise the risks of infection, flushing pipes should be undertaken before re-occupancy. This should ensure that all stagnant water is replaced with disinfected fresh water from the distribution main . Before use, hot water systems should be returned to an operating temperature of 60°C or greater and a circulation temperature exceeding 50° C to manage microbial risks, including those from Legionella.
Hand hygiene is extremely important to prevent the spread of SARS-CoV-2. Good hand hygiene practices need to be promoted, necessary equipment and supplies provided and operation and maintenance procedures imparted. Hand hygiene is required after the following critical times 2:
The handwashing technique is very important and includes wetting the hands with clean water, lathering the hands (including thumb, back of the hands, arm wrist, between the fingers and under the nails) by rubbing them with soap, scrubbing hands for at least 20 seconds, rinsing the hands under clean water and drying them either with a clean towel, on clean clothes or by air drying.
Handwashing frequency is important too, as evidence indicates that washing hands more frequently, even if for shorter durations, may be more effective and it directs and may have an influence on corresponding interventions (e.g. making handwashing as easy and convenient as possible). Handwashing facilities with water and soap or hand disinfectants should be available at homes, schools and public spaces (e.g. markets, places of worship, transportation centres). Water and soap should be available within 5m of toilets and at entrance and exit of all public spaces . When soap and water are not available within households, the use of ash can be considered. Ash may inactivate pathogens by raising the pH. Finally, washing with water alone, although the least effective option, can result in reductions in faecal contamination on hands and in diarrhoea .
Ideally pedal-operated taps, self-closing taps, elbow-operated levers or devices with sensors should be used to minimise hand contact. However, for people with disabilities (e.g. wheelchair users) a hand operated option may still need to be considered. Where standard taps are in use, ensure taps are regularly disinfected. If possible provide paper towels to use when opening/closing taps . Hygiene promotion and behaviour change campaigns are important to actively engage with individuals and communities and to inform the public about the risks of SARS-CoV-2 and protection measures against it. The following recommendations should be considered for campaigns :
When the use of mass media communication is not possible and physical meetings are required to reach the target population hygiene promoters should follow special safety measures to reduce transmission risks. Transmission risks are particularly high in facilities like health care or shared sanitation facilities and indoors, when several people meet and stay for a longer period of time or when aerosols are released through speaking, singing, laughing or eating.
Key behaviours to be addressed (besides handwashing) include:
Special SWM precautions are required in situations with high infection risks. These include health care facilities as well as waste disposal points of personal protective equipment (PPE) of workers working in high-risk situations (e.g. cleaning of shared toilets). Workers who handle health care or infectious waste should wear appropriate PPE (long-sleeved gown, heavy-duty gloves, boots, mask, and goggles or a face shield) during all steps of the waste processing and perform hand hygiene after removing it.
Health care waste includes all the waste generated by healthcare facilities, medical laboratories and biomedical research facilities, as well as waste from minor or scattered sources . About 85% of the total amount of waste generated by health-care activities is non-hazardous waste, comparable to domestic waste. The remaining 15% is considered hazardous material that may be infectious, like COVID-19, chemical or radioactive.
Infectious waste either generated by quarantined people with confirmed COVID-19 infection (e.g., sharps, dressings, pathology waste), or PPE from people who worked under infective conditions need to be safely packed in plastic bags and disposed-off. Preferred treatment options include high temperature dual chamber incineration or autoclaving . Where no standard waste managed processes exist burying or burning can be a temporary emergency solution . Where there is no off-site treatment for faecal sludge, in-situ treatment can be done with 10% lime slurry . Chlorine is not effective for disinfecting matter containing large amounts of solid and dissolved organic matter as faecal sludge .
Many municipalities report a large increase of medical waste generated in hospitals (5 times greater than before the pandemic), especially through the use of PPE . Therefore, it is important to increase capacity to handle and treat it without delay.
Health care waste can have negative health and environmental impacts, such as the unintended release of chemical or biological hazards or drug-resistant microorganisms. Taking steps to ensure safe and environmentally sound waste management can protect the health of patients, healthcare workers, and the environment .
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