Where Bang Bua Thong flooded in 2026

According to Siam News, Bang Bua Thong district declared a flood disaster area on 28 September 2026 covering seven subdistricts: Lahan (villages 1 to 9), Lam Pho (villages 1 to 8), Sano Loi (villages 1 to 6), Bang Bua Thong (villages 1 to 3, partly), Phimon Rat (villages 1 to 3, partly), Bang Rak Phatthana (villages 1, 3, 5 and 6) and Bang Rak Yai (villages 1, 2, 6 and 7). Flooding began on 25 September. Daily News reported that Highway 340 in the Bang Bua Thong section had about 30 centimetres of water over a stretch of roughly three kilometres.

Bang Bua Thong mixes housing estates, older canal-side communities, markets and a large number of childcare centres. Many young families who commute into Bangkok and central Nonthaburi leave their children with a nursery or with grandparents during the day. When those homes and centres flood, the risk to small children rises sharply.

The story below is a typical scenario drawn from situations that commonly follow floods. It does not describe any particular family.

Fon brings her eighteen-month-old son back to their house in a Lahan housing estate two days after the water recedes. The family shovels out the mud, hoses the floors and leaves fans running to dry them. Her son is delighted to be back on the living-room floor and immediately chews on a toy car that had been floating around the house. Two days later he starts vomiting, then has watery diarrhoea several times a day with a fever. The nappies run out faster than ever, and Fon takes him to a doctor, who says the symptoms fit a viral gut infection and stresses the importance of preventing dehydration.

What Fon did not know on clean-up day was that hosing with plain water and rinsing toys in still-cloudy tap water is not enough for a hardy virus like rotavirus, and that toys which floated in floodwater should be cleaned and disinfected, or thrown away, before a child touches them.

What is rotavirus, and why is it tougher than it looks?

The name comes from the Latin rota, meaning wheel, because under an electron microscope the virus particle looks like a wheel. Rotavirus belongs to the Reoviridae family, carries double-stranded RNA and, like norovirus, is a non-enveloped virus. That makes it survive well on hands, toys and hard surfaces, and makes it more resistant to ordinary soap residues and alcohol than viruses with a fatty envelope.

WHO and the CDC both identify rotavirus as a major cause of severe diarrhoea in infants and young children. Without vaccination, nearly every child in the world is infected at least once before the age of five. The first infection is usually the most severe; later ones tend to be milder. Adults can be infected too but usually have mild or no symptoms, which means grown-ups can carry it to children without realising.

In Thailand rotavirus is most common in the cooler, drier months, but it occurs all year. When a flood wrecks sanitation, the season stops being what decides the risk.

The good news is that there is an oral rotavirus vaccine for infants that greatly reduces severe disease. It must be given within set age windows. Parents who are unsure whether their child is fully vaccinated should check the maternal and child health record book and ask a paediatrician or the local health-promoting hospital.

How rotavirus spreads after a flood

Rotavirus spreads mainly by the faecal-oral route. A sick child sheds very large amounts of virus in stool, starting before symptoms appear and continuing for a while after they stop. Floods widen every part of that route.

• Sewage in floodwater. Submerged toilets, septic tanks and drains release waste into the water. When it recedes, floors, lower walls, table legs and soaked belongings may carry faecal contamination.
• Toys and baby items. Small children mouth plastic toys, teethers, spoons, bottles and their own fingers after crawling on the floor. That is the shortest path from floor to mouth.
• Nappy changes. During a flood, changes happen on makeshift surfaces with little handwashing water, and used nappies may sit indoors for days because rubbish trucks cannot get in.
• Unsafe water. Preparing formula or rinsing bottles with water that is not clean is a risk many parents overlook in the chaos.
• Caregivers' hands. Adults who shovel mud and then pick up a baby or prepare food without washing with soap are the most important bridge of all.
• Nurseries reopening. When children from many homes gather again and one is shedding virus, shared toys and nap mats become relay points.

Because it takes very little virus to infect a child while a sick child sheds so much, an invisible trace of contamination is enough to start an outbreak in a home or a classroom.

Rotavirus diarrhoea in children: symptoms and danger signs

Symptoms usually begin about two days after exposure. Many children start with fever and vomiting, followed by frequent watery diarrhoea and sometimes stomach pain. The diarrhoea typically lasts three to eight days, long enough for a small child to lose a great deal of fluid and salts.

Dehydration is the main danger. Take the child to a doctor promptly if you see:

• much less urine, or nappies that stay dry for several hours
• crying without tears, a dry mouth and tongue
• sunken eyes, or a sunken soft spot on a baby's head
• drowsiness, unusual floppiness, difficulty waking, or unusual irritability
• vomiting so persistent that the child cannot keep fluids or milk down
• blood in the stool, high fever or severe tummy pain

Those most at risk are babies and children under five, especially those not yet vaccinated, those born prematurely and those with chronic illness or weakened immunity. Older adults and immunocompromised people in the same household can also become ill.

This article does not give medication or treatment advice. The general principle health authorities recommend is to replace fluids and salts as advised by a doctor or pharmacist and to keep breastfeeding as usual if the child is breastfed. If you suspect dehydration, see a doctor straight away rather than waiting.

Other post-flood infections can also cause diarrhoea in children, such as bacterial infections from food or water. For adults who waded through floodwater and then develop a high fever with calf pain, leptospirosis must be considered. Telling the doctor about floodwater exposure helps them reach the right diagnosis.

A rotavirus risk map for homes and nurseries after the flood

Look at the house from the eye level of a crawling child and you will see that almost every risk point is close to the floor.

• Living-room and bedroom floors, especially wood, laminate and tile grout lines that soaked up water. Children crawl and sit here all day.
• Play mats and rugs. Interlocking foam mats trap mud in their joints. If they sat in floodwater, consider throwing them away.
• Toys. Hard plastic toys can be washed, but soft toys, toys with holes, and battery toys that took in water are very hard to clean properly.
• Changing areas and bathrooms: changing pads, potties, toilet seats, taps and nappy bins.
• Bottle-prep corners: bottle sinks, bottle brushes, drying racks and sterilisers that may have been submerged.
• High chairs, small tables and cot rails that children chew and lick.
• In nurseries: nap mats, child-height toilets and sinks, shoe racks and shared toy boxes.

When one child falls ill, the whole household feels it

The child's health. Several days of diarrhoea leave a child weak, eating little and losing weight. Some need hospital care for fluids, and getting to hospital is hard while main roads such as Highway 340 are still under water.

Everyone else at home. Siblings, grandparents and the parents doing the caring can catch it, especially in multi-generation households.

Work and income. Parents take leave to care for a sick child just when they already need leave to repair the house. A nursery with several sick children may have to close temporarily, affecting the owner and every family that relies on it.

Trust in the nursery. Parents will always ask how the centre cleaned and disinfected after the flood. A clear answer backed by records helps them decide to send their children back sooner.

Common mistakes when cleaning a home with small children

1. Hosing the floor and calling it clean. Water carries mud away but does not inactivate viruses stuck to surfaces.
2. Using hand gel instead of handwashing. Rotavirus is non-enveloped, so washing with soap and clean water matters more, particularly after nappy changes.
3. Keeping flood-soaked toys. Soft toys, toys that let water inside and anything that cannot be washed should go.
4. Mixing strong chemicals in a child's room. Over-strong products irritate small children, and different cleaners must never be mixed.
5. Blowing fans over a damp, dirty floor. It dries faster, but if the floor is not clean you are just drying the grime in place.
6. Bringing toddlers home on mud day. Mud dust, dirty water and cleaning chemicals are not for small children. Let them stay elsewhere until the house is ready.
7. Disinfecting only the flooded rooms. People track mud across the house, onto stairs, into upstairs rooms and into the car.

WHD post-flood disinfection spraying and childhood diarrhoea viruses

World Health Disinfection (WHD) provides a disinfection spraying service for homes, housing estates, nurseries, schools and buildings. According to the service information, trained technicians spray and/or apply ULV (Ultra Low Volume) fogging, a fine mist that settles evenly on surfaces, including the low corners where children crawl. The disinfectant is CHEMGENE HLD4H, a medical-grade disinfectant from the United Kingdom containing Benzalkonium Chloride and Didecyldimethylammonium Chloride.

Being clear about rotavirus. According to the product and service information, the disinfectant is broad-spectrum, covering viruses, bacteria and fungi. The organisms the website names are SARS-CoV-2 (COVID-19), Human Coronavirus 229E, RSV, influenza H1N1 and H5N1, HIV, norovirus, hand-foot-and-mouth virus, vaccinia virus, mycobacteria, Salmonella and Bordetella pertussis. The service page states 99.99% effectiveness and the product page states 99.85% against COVID-19 within one minute. Rotavirus is not on that named list, so we do not claim a tested kill result against it. What we can say is that rotavirus belongs to the virus group the product says it covers, and that WHO and the CDC advise cleaning and then disinfecting flood-contaminated surfaces. If a nursery or school wants test data for rotavirus specifically, ask WHD directly before deciding.

The service page lists approvals and endorsements from Thailand's Department of Medical Sciences, Mahidol University, NHS England and EN 14476:2013+A2:2019. Customers include hospitals, schools, shopping malls, airports, offices, airlines, banks and residential buildings.

How the service works for homes with small children

1. Book. Call 065-556-6294 or LINE @whd268. Give the size of the house, the number of floors and how high the water came, and tell the team there are young children in the home.
2. Prepare. Remove mud, wash floors and lower walls with water and detergent, discard soft toys and anything soaked that cannot be washed, and pack bottles, teats, baby spoons, food and personal items into closed boxes.
3. Technicians spray. Floors, lower walls, bathrooms, changing areas and high-touch surfaces are treated. Children, older adults, everyone else in the household and pets stay outside the zone being sprayed.
4. Wait, then return. According to the service information, the space can be used normally after about 30 minutes. Follow the re-entry time the technicians give on site, and ask them before letting a child crawl on the floor or putting mouthed toys back down.

Straight talk on limits: spraying comes after mud removal and washing. It does not replace cleaning, handwashing after nappy changes, vaccination or taking your child to a doctor, and we do not claim it leaves no residue at all. Rinse mouthed toys, bottles and food containers with clean water again before use.

10 reasons Bang Bua Thong homes with young children should book spraying after the flood

1. Children live closest to the floor. The floor that sat in sewage-laced water is your child's playground, so disinfecting surfaces after washing is worth it.
2. Fine mist reaches cracks and gaps: grout lines, skirting boards, table legs and under cabinets that a mop misses.
3. A product stated to cover many germ groups. After floods there are viruses, sewage bacteria and fungi. Details are on the disinfection service page.
4. Parents do not have to mix chemicals at home. Less risk of wrong dilutions or mixing incompatible products.
5. Trained technicians know where to spray and how to advise on re-entry.
6. Short turnaround. According to the service information, about 30 minutes before the home can be used again.
7. Right for nurseries and kindergartens before children return, giving parents evidence-based answers.
8. Endorsements you can check: the Department of Medical Sciences, Mahidol University, NHS England and EN 14476, as listed on the service page.
9. Organism-specific data on request. If you want results for rotavirus in particular, ask WHD before you decide.
10. Something to keep at home. According to the service information, the promotion includes a CHEMGENE spray bottle and WELLGIENIC wet tissues, and tax invoices are available. See details and book.

Before and after: a home ready for crawling again

Example case: a Bang Rak Phatthana nursery before reopening

This example case is assembled from common situations to explain the process. It is not a review from any particular customer.

Prae runs a small childcare centre in a two-storey house in Bang Rak Phatthana. During the flood, water entered the ground floor, where the playroom and nap room are. She closed immediately and carried what she could upstairs. Once the water dropped, parents in the LINE group began asking when she would reopen and how they could be sure the rooms were safe.

Prae started by throwing out the foam play mats, soft toys and nap mattresses that had soaked. She washed floors, lower walls and the children's bathroom with detergent and kept the windows open for several days to dry everything. Then she booked WHD. The technicians walked through first and set zones: playroom, nap room, children's bathroom, food-prep corner and entrance. Nobody was in the house during spraying. After the technicians' re-entry time had passed, Prae ventilated the rooms, rinsed the plastic toys that children mouth with clean water again, and set the rooms back up.

Before reopening she messaged parents to explain every step, asked them to check their children's vaccination records, and asked that any child with diarrhoea or vomiting stay home until fully well. Several parents replied that seeing exactly what the centre had done put their minds at rest.

Rotavirus prevention checklist for homes with young children

Before spraying

• Keep toddlers with relatives or somewhere safe during mud removal and cleaning.
• Adults cleaning wear rubber gloves and boots and wash hands with soap before picking up a child.
• Discard play mats, soft toys, children's mattresses and toys that soaked and cannot be cleaned.
• Wash floors, lower walls and any furniture a child can reach, then dry.
• Throw away formula, baby food and medicines that touched floodwater.
• Show the technicians the changing area, bathrooms and anywhere the toilet overflowed.

After spraying

• Re-enter at the time the technicians give and open the windows.
• Rinse bottles, teats, spoons and mouthed toys with clean water again.
• Use boiled water or sealed bottled water to prepare formula and baby food.
• Wash hands with soap and water after every nappy change, after the toilet and before preparing food.
• Seal used nappies in a tied bag and put them in a lidded bin.
• Check your child's vaccination record and ask a doctor about rotavirus vaccine for their age.
• If your child has diarrhoea or vomiting, watch for dehydration and see a doctor at once if anything worries you.

Frequently asked questions about rotavirus and post-flood spraying

Does CHEMGENE HLD4H kill rotavirus?
Rotavirus is not on the list of organisms the website names, so we do not claim a direct test result. The product is stated to cover several germ groups, including viruses. If you need rotavirus-specific test data, ask WHD directly.

My child has had the rotavirus vaccine. Do I still need to be careful?
The vaccine greatly reduces severe illness, but handwashing, safe water and cleaning after a flood are still needed because other germs also cause diarrhoea. Ask your paediatrician about vaccination.

Can my baby crawl on the floor right after spraying?
Re-enter at the time the technicians give and ask them before letting a child crawl or putting toys on the floor. According to the service information, the space can be used normally after about 30 minutes.

Can I clean with bleach myself?
Yes, if you follow the label, dilute correctly, ventilate well, never mix it with other products and keep children out while you work. Professional spraying is an option when the area is large or you want thorough coverage.

Which toys can I keep?
Hard plastic toys without openings can be washed and disinfected. The CDC advises throwing away soft toys, foam toys and toys that let water inside if they were in floodwater.

Can adults catch rotavirus?
Yes, but usually with mild or no symptoms, so they can pass it to children unknowingly. Soap handwashing matters for everyone in the home.

The house still smells musty. What else can I do?
Get the house completely dry first. For musty air, the residential ozone disinfection service can be a complementary option; it must be done in an unoccupied space.

Get the house ready before your little one crawls again

Talk to WHD about post-flood disinfection spraying for homes, housing estates, nurseries and schools in Bang Bua Thong and across Nonthaburi.

Book disinfection spraying with WHD

Phone 065-556-6294 · LINE @whd268 · worldhealthdisinfection@gmail.com

Related links

• WHD disinfection spraying service
• CHEMGENE HLD4H disinfectant
• Residential ozone disinfection service

References

• Siam News, Bang Bua Thong flood disaster area declaration (28 Sep 2026): siamnews.com, and Daily News reporting on Highway 340
• WHO fact sheets: who.int/news-room/fact-sheets
• CDC Floods: cdc.gov/floods and CDC Rotavirus: cdc.gov/rotavirus
• Thailand Department of Disease Control: ddc.moph.go.th