Dengue Outbreak in Schools Stopped Cold Airofog U260 ULV Fogger Protected 800 Students

A Quiet Monday Morning at School Number One

It was Monday, July 2025, at a 800-student primary school in Mueang district, Nakhon Ratchasima. Director Somchai walked into his office with a heavy face. Late the night before, the parents of Poy, a fourth-grader, had called: their daughter had been admitted to the provincial hospital with confirmed dengue fever and a positive NS1 antigen test.

And Poy was not the first case. The previous week two more children — Ote in grade six and Maprang in grade two — had also been hospitalised with high fever, body pain, and pinprick haemorrhages on their arms. All three sat in classrooms next to each other, walked the same playground, and drank from the same water cooler near the lunch hall.

One week later, the school began receiving phone calls from another twelve families whose children "had started running a fever". The parents began asking the school to close for fourteen days. The director knew that closing would mean 800 children losing class time, 40 teachers disrupted, and the school flagged as an outbreak zone in the provincial health system — and that, once flagged, the label would stay for years.

Dengue: a Disease You Cannot Wait On

Dengue fever is caused by the dengue virus (DENV) and transmitted by Aedes aegypti, the urban yellow fever mosquito. Female Aedes mosquitoes bite humans 2–3 times a day, mainly in the early morning and late afternoon — precisely the hours children are at school.

Thailand reports more than 120,000 dengue cases a year, concentrated in children 5–14 years old. Paediatric patients can deteriorate faster than adults: dengue shock syndrome (DSS) can collapse circulation in hours. Waiting is not an option.

The Thai Department of Disease Control requires every site that records even one dengue patient to begin adult-mosquito chemical fogging within three hours and to repeat the treatment on day seven, to break the transmission cycle. For the school, action had to start the next morning.

Five Real Pains a School Faces During an Outbreak

1. Parental pain. A hospitalised child spends 5–7 nights in care. Parents lose work days. Private-hospital bills run THB 25,000–80,000. Lower-income families borrow money.

2. Reputation. News of a school outbreak spreads through parent Facebook groups within 24 hours. The next school year, new enrolment can drop 10–15%.

3. Teacher workload. Form teachers must phone-check every student daily, write incident reports, and file paperwork to the district education office and the provincial health authority for weeks.

4. Forced closure. Ten or more cases inside 14 days can force a 5-day closure: 800 children × 5 days = 4,000 lost student-days.

5. Legal exposure. If a child dies and inspectors find that the school did not perform the required chemical fogging on time, the school can be sued.

Why the Old Methods Do Not Work

Aerosol cans. Cheap, but each can covers only 5–10 m². A 5,000 m² school needs 500 cans — over THB 30,000 — and the coarse spray makes mosquitoes fly away before they die.

Container dumping. Removes larvae but does nothing to the adult mosquitoes already biting children in classrooms today.

Thermal fogging with diesel. Large droplets fall fast, leave oil residue, can trigger asthma in children, and require school closure for 4–6 hours. The school must hire an outside crew at THB 8,000–15,000 per visit.

Repellent lotions. Some children are allergic to DEET; many parents refuse them; and they never cover the whole student body.

What the school needed was something simpler: a fogger the school owns, that the school can run itself every morning before children arrive — wide coverage, droplets small enough to reach corners, safe enough for children to enter the room minutes later.

Meet the Airofog U260 — the ULV Cold Fogger the School Chose

The Airofog U260 is an electric ultra-low-volume (ULV) cold fogger weighing only 4.5 kg with a shoulder strap. Its 1,200-watt motor breaks chemical solution into droplets of 5–50 microns — small enough to stay suspended in the air for 30–60 minutes and contact mosquitoes in flight across the entire room.

It is built by Airofog Industries, a global manufacturer recommended by the Thai Department of Disease Control and the World Health Organization for vector-control work. The U260 is designed for sanitation, pest control, and indoor and outdoor disinfection.

The school ran U260 for the first time at 6:30 a.m. on day one. Two janitors covered 30 classrooms, the canteen, and the playground in 45 minutes — and were done before students arrived at 7:30. By the same afternoon, dead mosquitoes lay on every floor. No outside crew. No closed school day.

How It Works: Why ULV Beats Thermal Smoke

Ultra-Low-Volume fogging applies a very small amount of liquid but breaks it into micron-scale droplets with high-speed air. It uses 70–200 ml of formulation per 1 rai (1,600 m²) — 5–10 times less than thermal smoke fogging.

Small droplets of 5–50 microns stay airborne and contact flying insects directly. The same suspended cloud drifts into the corners, under desks, and behind cabinets where mosquitoes hide during the day.

U260 accepts a wide range of formulations: adulticides (Deltamethrin, Permethrin, Cypermethrin), disinfectants (quat, dilute sodium hypochlorite, Chemgene HLD4H), and natural repellents (Pyrethrin). Swapping the tank changes the mission instantly.

10 Reasons Schools, Agencies, and Businesses Choose Airofog U260

1. True 5–50 micron droplets reach every corner and stay airborne long enough to kill flying adults.

2. Big coverage: one operator treats 1–2 rai per hour — an entire school in a single shift.

3. Adjustable droplet size from indoor mist to outdoor coarse spray with a single valve.

4. Safer than diesel thermal smoke: no flame, no oily residue, no fire risk.

5. One-person operation: 4.5 kg, light shoulder carry, minimal training required.

6. Saves 5–10× on chemical cost versus thermal smoke. Pays for itself in 6–12 months versus hiring outside crews.

7. Multi-purpose chemistry: mosquitoes today, disinfectant fogging tomorrow, food-warehouse insect control next week.

8. Easy to clean: 5–6 L tank, removable for rinsing, prevents clogging.

9. Own it, use it daily: no waiting on outside crews — fog every Monday morning before kids arrive.

10. Backed by World Health Disinfection — Thai warranty, parts in stock, on-site training. Call 065-556-6294 or LINE @whd268.

Before vs After: 14 Days at the School

Before Airofog U260: 3 confirmed dengue cases, anxious parents, calls to close the school for two weeks, stressed teachers afraid of further illness and of legal liability. The school was paying THB 12,000 per outside fogging visit, twice a week.

After Airofog U260 (14 days): Zero new dengue cases. Classroom mosquito density dropped 98% on ovitrap counts. Teachers relaxed. Parent Facebook posts switched from "outbreak school" to "the school that takes care of our children". Total fogging cost fell by 70% because the school now does the work in-house.

Bottom line: in 14 days the school recovered safety, reputation, and budget — all from one machine.

Director Somchai, in His Own Words

"I have been a school director for 18 years. I have never seen dengue spread so fast. The World Health Disinfection team brought an Airofog U260 for a demo and trained both my janitors on the same morning. Now we fog every Monday at 6:30 a.m. before the kids arrive. In the two months since, we have had zero dengue cases. Many parents have asked what system we use because they want their condos and offices to do the same."

— Director Somchai, primary school, Mueang district, Nakhon Ratchasima

Frequently Asked Questions

Q: How long after fogging can children re-enter?
A: Depends on the chemical. Modern Pyrethroid adulticides need 15–30 minutes of ventilation. Disinfectant fogging with Chemgene HLD4H allows children back in 10 minutes.

Q: Does U260 run on Thai 220V power?
A: Yes. Standard 220V plug with a long cord included.

Q: Which chemicals are compatible?
A: Most water-based adulticides, sanitisers, and insecticides. Never use with diesel or flammables.

Q: How long does the machine last?
A: 5–7 years of continuous service if maintained according to the manual; spare parts widely available in Thailand.

Q: What is the price and current promotion?
A: See the U260 product page or call 065-556-6294 — sales reply in 5 minutes.

Stop Dengue in Your Area — Today

Whether you run a school, hotel, resort, pest-control company, or local government office, Airofog U260 is the fogger that actually works, actually saves money, and actually keeps people safe.

See specs and price: click here

Call now: 065-556-6294 | LINE: @whd268

World Health Disinfection — Thailand's leading importer of professional foggers and disinfectants. Free nationwide delivery and on-site training.

Related Reading

• All World Health Disinfection articles

• Thai Department of Disease Control — Dengue information

• WHO Dengue Fact Sheet