Cleaning up the home after a flood – developing country situations updated December 2007

This leaflet has been put together to provide advice and background information on cleaning up the home after floods. It also gives advice on post-flood decontamination of drinking water sources and treatment of water for domestic use during the flood. This advice sheet focuses on key issues for middle and lower income communities in developing country situations. For more detailed information consult our other advice sheet entitled “Coping with floods, cleaning up afterwards – and staying healthy”.

Background Flooding is the most common type of natural disaster worldwide – 40% of all natural disasters. Whilst the numbers of other types of natural disasters continue to decrease the number of floods continues to rise.

Every year in South East Asia, hundreds of millions of people living in lowland river- line or coastal areas are affected by flooding.

Quite apart from the devastation caused by the Tsunami in South East Asia, many countries in Asia, Africa and Latin America are regularly devastated by floods during the monsoon season. In South East Asian countries such as India, Bangladesh, Myanmar, Nepal, Laos, Vietnam etc. monsoon floods and cyclones are almost an annual phenomena. The 1999 cyclone in Orissa (India) killed 10,000 people and affected 10-15 million people. In Bangladesh the devastating floods of 1991 and 1998 affected more than 30 million people, and the death toll was 1,40,000. The recent floods in China and Korea have made more than 2 million homeless. Torrential rain and flooding hit the Dominican Republic and Haiti with drastic effects. In Prague, in 2002, more than 35,000 people were evacuated from their homes when the Vltava River burst its banks. In 2003, there was significant flooding in Florida and Jamaica following the hurricanes which hit the area. In the UK five million people live in places with a risk of flooding.

Cleaning up after a Flood. Floods present obvious health risks including drowning, electrical shock and starvation. Advice and fact sheets on what to do before a flood, once the flood arrives and after a flood can be found on the Federal Emergency Management Agency (FEMA) website http://www.fema.gov/. Floods can also bring the risk of epidemic disease, which if not addressed appropriately can persist in the environment a long time after the flooding has ceased. This is exacerbated in hot climates. Flood water affecting the home or other property is likely to be heavily contaminated with sewage and other organic material such as animal carcasses and, therefore, it must be assumed that it is contaminated with human pathogens (germs). It may take a long time to dry out after flooding, especially in humid climates, and moulds can establish and grow on surfaces causing spoilage of items. Thorough cleaning and disinfection is recommended on all surfaces affected. Ventilation is also important in order to assist the drying process.

General guidelines when cleaning up are as follows:  Protect yourself from floodwater and other possible sources of germs as much as possible, taking care to cover open cuts and wounds on exposed skin. Waterproof dressings, rubber gloves and a mask to cover the nose and mouth are ideal if available. It is advisable to wear rubber boots in case there has been a backflow of sewage into the house.  Do not let children play in floodwater and wash their hands frequently, particularly before eating food.  As soon as possible, remove and bury any faecal material from humans or animals to prevent spread of germs. The risk of spread of germs from residues of faecal material can be reduced by application of concentrated bleach solution*. This can also help reduce the infection risk to those involved in cleaning up the area.  Food or drink suspected of being contaminated should be thrown away.  As soon as possible, transfer all refuse to secure plastic bags or other containers to prevent the spread of germs until the refuse can be taken away.  Remove as much silt and water as possible from the home. Good ventilation and heating of the home will speed up the drying process, and prevent mould growth and reduce the risk of spread of germs.  Remove and discard contaminated household materials such as furnishings and fittings that are damaged beyond repair e.g. wall coverings and rugs.  All hard surfaces should be hygienically cleaned either by cleaning followed by disinfection or by using a disinfectant/cleaner**. Be particularly careful to thoroughly disinfect surfaces that may come into contact with food, such as work surfaces, food storage shelves, refrigerators etc. Areas where small children play should also be carefully cleaned and disinfected. Allow all surfaces to dry thoroughly – good ventilation and heating will speed up the drying process.  For areas where mould has already begun to develop, a concentrated solution of bleach* may be used to kill the mould and whiten and remove the black stains that the mould produces. When the surface is visually clean, clean again with a fresh solution of bleach in order to kill any remaining non-visible mould spores. Allow all surfaces to dry thoroughly.  For those items which are not irreparably damaged, but which cannot be washed or dry-cleaned, such as mattresses, air dry them in the sun and then if there is no risk of colour damage spray them thoroughly with a solution of bleach.  Bedding, clothing and other soft / fabric articles including children’s toys etc should be laundered according to IFH guidelines***  Any item that comes into contact with food such as crockery, cutlery, utensils and cooking equipment MUST be “hygienically cleaned”** before re-use. If an adequate supply of hot water is available this can be done by detergent-based cleaning followed by thorough rinsing. Otherwise the items should be cleaned and then disinfected by soaking in a solution of bleach**.

Page 2/6  Do not be tempted to salvage foodstuffs. Any food item that has been in contact with floodwater should be regarded as contaminated and discarded. If it is not possible to reach shops, eat canned food, provided that the can has not been punctured, corroded or damaged in any way and is not showing any signs of bulging or leakage. It is recommended to thoroughly clean and then disinfect the lid of the can with a solution of bleach to prevent any contaminants from entering into the contents on opening. If the contents of the can have an unpleasant odour or colour or if the food looks mushy and the liquid cloudy, dispose of the can in a sealed plastic bag. NEVER even taste the food from cans that show any signs of spoilage in order to avoid the risk of botulism poisoning  Never use untreated floodwater for drinking, food preparation and cooking. Advice on treatment of water is given below.

* Concentrated bleach In situations where concentrated bleach is required a solution containing not less than 4.5% or 45,000ppm available chlorine should be used

**Hygienic cleaning of surfaces Since flood water affecting the home or other property is quite likely to be contaminated with sewage, animal faeces, refuse etc. it is important that all surfaces are “hygienically cleaned” in order to get rid of germs as well as visible dirt. Hygienic cleaning of surfaces can be achieved in a number of ways according to the extent of the contamination and the facilities available:  Cleaning using detergent (liquid or soap) and hot water. Detergent and hot water cleaning can be used to produce a hygienically clean surface provided that the surface is then thoroughly rinsed using clean (potable) running water. Mechanical action using a cloth, sponge or brush to maximise removal of soil and microbes is an important part of the process. Removal of soil by wiping with a cloth without subsequent rinsing is not considered sufficient to achieve a surface that is hygienic. Use of a contaminated cloth can actually spread pathogenic organisms onto previously uncontaminated hands and hand and food contact surfaces.  Cleaning using soap or detergent and a disinfectant product. This process should be used on large surfaces which cannot be rinsed or for situations where an adequate supply of running water is not available. - If the surface is heavily soiled, clean thoroughly to remove the visible soil using a solution of detergent or soap. Using a clean cloth apply a solution of bleach, diluted to 0.5% or 5000ppm available chlorine, to the surface. Since disinfectants are inactivated to a greater or lesser extent by the presence of soil, heavily soiled surfaces MUST be cleaned before application of a disinfectant. - If the surface is only “superficially“ dirty, it may be hygienically cleaned using a combined bleach/cleaner containing 0.5% or 5000ppm available chlorine. The solution should be applied with a clean cloth or via a spray bottle and the surface then wiped. If necessary repeat the process until the surface appears visibly clean. Household bleach (both thick and thin bleach) for domestic use typically contains 4.5 to 5.0% available chlorine. Bleach/cleaner formulations (e.g. sprays) are formulated to be used “neat” (i.e. without dilution). It is always advisable however to check he

Page 3/6 label as concentrations and directions for use can vary from one formulation to another.

*** Hygienic cleaning of laundry Laundry can be made hygienically clean by:  washing at 40-60°C with a bleach-based product (check ingredients on the package)  washing at 60°C or above (using any product as the higher temperature kills germs). Washing at temperatures of 40°C or less with a non bleach product is considered to carry a risk of inadequate decontamination.

Why use Bleach? Bleach contains hypochlorite. It is highly effective against viruses, bacteria, yeast and moulds. Bleach acts very quickly (within 1 minute) but longer times are required for killing moulds and fungi. Bleach is also an excellent “cleaner” for the removal of mould growth. Bear in mind that chlorine-based bleaches can damage and/or bleach fabrics, carpets and soft furnishings. It can also corrode metal surfaces

Post flood decontamination of drinking water sources and treatment of water for domestic use during the flood.

Decontamination of drinking water sources after the flood. In rural areas such as those in South East Asian countries such as Myanmar, Nepal, India, Bangladesh, Laos, Vietnam etc. many or most of the tube wells/dug wells that serve as sources for domestic water supply (both for private and public supply) become grossly contaminated with faecal matter during the floods. Unless they are thoroughly decontaminated (super chlorination), during the post flood situation, water borne infections such as diarrhoea, dysentery, typhoid, infectious hepatitis etc. are likely to occur. Super Chlorination of these contaminated sources can be achieved by adding chlorine to the water (in the form of bleaching powder (calcium hypochlorite) or bleach solution) and ensuring a contact period of 24 hours. The final concentration of chlorine in the water should be 25-50mgm/l available chlorine. For further details on how to prepare and dilute chlorine solutions consult the WHO website: http://www.who.int/water_sanitation_health/hygiene/envsan/tn05/en/index.html

Treating water in the home to make it safe for drinking During the flood, supply of safe and potable water to the isolated population is a serious problem. Point-of-use treatment of the turbid floodwater to make it drinkable can be undertaken with a simple technique of coagulation, flocculation and disinfection.

Pretreatment of turbid water Turbid water should be filtered through a cotton cloth to remove any solid materials, treated with alum and bleaching powder, stored for at least 2h and then decanted or

Page 4/6 filtered through a clean cloth. For pre-treatment add 10g alum and 5g lime per 100l of turbid water.

Treatment to eliminate pathogens 1. Chemical disinfection Where chlorine or iodine tablets are available, they should be used as directed by the manufacturer. Alternatively water should be disinfected with hypochlorite in the form of bleaching powder or hypochlorite solution for 30 mins. The final concentration of chlorine should be 0.5-1mgm/l available chlorine after 30 mins. The amount of chlorine needed depends mainly on the concentration of organic matter in the water and should ideally be determined for each situation using a test kit. If this is not available, a slight smell of chlorine is a crude indicator. For details on preparing chlorine solutions consult: http://www.who.int/household_water/resources/emergencies.pdf

For disinfection with iodine a concentration of 3.7 mg/l, contact time 10 mins, is required (6.3 mg/l if virucidal contamination is suspected).

2. Boiling Bringing water to a rolling boil will kill pathogens effectively, except at high altitudes. A holding period of 3-5 mins will ensure that water is safe, except in situations where contamination with spore-forming bacteria, fungal or protozoal cysts or hepatitis virus is suspected, in which case 10 mins is advised.

Other methods for disinfection of household water are available including filtration, solar disinfection, UV irradiation and combined flocculation/disinfection systems. Further details of these methods can be obtained from the IFH teaching/self learning resource on home hygiene.

Advice on such treatment of water can also be obtained from:  Emergency treatment of drinking water at point-of-use. WHO technical note for emergencies No. 5 http://www.who.int/water_sanitation_health/hygiene/envsan/tn05/en/index.html  Household Water Treatment and Safe Storage Following Emergencies and Disasters http://www.who.int/household_water/resources/emergencies.pdf  IFH information and hygiene advice sheet - “Safe water in the home: household water treatment and safe storage”

Useful sources of Information. IFH teaching/self learning resource on home hygiene: Home Hygiene in Developing Countries: Prevention of Infection in the Home and Peridomestic Setting. A training resource for teachers and community health professionals in developing countries http://www.ifh- homehygiene.org/ IntegratedCRD.nsf/571fd4bd2ff8f2118025750700031676/19155ab46073 e67f8025752200546d83?OpenDocument 1. Storm-Related Mortality by Center for Disease Control and Prevention (CDC). www.bt.cdc.gov/disasters/floods. 2. UNICEF water and sanitation in emergencies. http://www.unicef.org/wes/index_emergency.html Page 5/6 3. IRC water and Sanitation Resource Centre. Information and knowledge support on water sanitation and hygiene issues associated with flooding in developing country situations http://www.irc.nl/page/15675. 4. WHO Technical notes for emergencies http://www.who.int/water_sanitation_health/hygiene/envsan/technotes/en/index. html These four-page illustrated notes have been prepared to assist those working immediately or shortly after an emergency to plan appropriate responses to the urgent and medium-term water and sanitation needs of affected populations. The notes are relevant to a wide range or emergency situations, including both natural and conflict-induced disasters.

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