Hong Kong Records 602 School Flu Outbreaks Since Term Began as a Paediatrician Warns It Is Worse Than Previous Years: A True Story from 2025 and Lessons for Primary Schools
Last updated: 9 Nov 2026 | 16 Views |
Hong Kong Records 602 School Flu Outbreaks Since Term Began as a Paediatrician Warns It Is Worse Than Previous Years: A True Story from 2025 and Lessons for Primary Schools
Hong Kong recorded 602 school flu outbreaks within weeks of term starting, and a University of Hong Kong paediatrician warned that more than half of schools had some level of outbreak. It holds lessons for Thai primary schools with hundreds of pupils per grade.
The True Story: 602 School Outbreaks Since Term Began
On 23 October 2025, Hong Kong's Centre for Health Protection (CHP) had recorded 602 influenza outbreaks in schools since the new academic year began, compared with 88 in the whole previous winter season, and 13 severe or fatal child cases this term.
Professor Patrick Ip Pak-keung of the University of Hong Kong's paediatrics department said more than half of Hong Kong's schools had reported some level of outbreak, calling it more serious than previous years and warning it could continue into November and December. He advised daily temperature checks, masks for symptomatic students and keeping sick children home.
The Key Lesson: When Over Half of Schools Have Outbreaks, Nobody Escapes by Luck
Thai primary schools have hundreds of children learning, eating and playing together every day. Points to watch are:
- Classrooms of 40 sitting close all day
- Canteens where every grade eats at once
- Restrooms and sinks where soap often runs out
- Playgrounds and sports equipment touched in turn
- Small sick bays where sick children wait for parents
How Flu Spreads
According to the World Health Organization, seasonal influenza spreads easily where people gather, such as schools and nursing homes. It spreads through droplets when people cough or sneeze, and through hands that touch contaminated surfaces and then the eyes, nose or mouth. Most people recover within a week, but young children, older adults, pregnant women and people with chronic illness are at risk of severe disease. Influenza is an enveloped virus, which suitable disinfectants can inactivate.
Risk Register for Primary Schools
- Children with fever attend: likelihood high / impact high / level critical. Mitigation: daily fever checks and parent pick-up. Owner: gate duty teacher
- Soap often runs out: likelihood high / impact medium / level high. Mitigation: check and refill soap daily. Owner: caretaker
- Crowded canteen: likelihood high / impact medium / level high. Mitigation: stagger meal times and wipe tables every round. Owner: facilities team
- Sick bay not cleaned after sick children: likelihood medium / impact medium / level medium. Mitigation: change sheets and ozone-treat the sick bay on a schedule. Owner: school nurse
- No procedure when several children in a class fall ill: likelihood medium / impact high / level high. Mitigation: inform health officials and fog the classroom at once. Owner: head teacher
Ways to Reduce Flu Risk in Primary Schools
- Check temperatures every morning at the gate
- Give masks to symptomatic children and call parents
- Refill soap at every sink daily
- Stagger meal times to reduce crowding
- Wipe desks, handles and rails several times a day
- Hold a vaccination day with the local health centre
- Fog and ozone-treat classrooms when several fall ill
How ULV Disinfection Fogging Helps
The World Health Disinfection disinfection service uses ULV fogging machines that turn the disinfectant into a fine mist. It settles across the whole area, including corners, curtains, upholstery and surfaces that hand wiping cannot reach.
- Whole-area coverage without relying on wiping spot by spot
- Quick return to use, typically about 30 minutes after fogging
- Uses Chemgene HLD4H, which meets EN 14476 for virucidal activity according to the product page
- The team wears full protective equipment, so owners and staff do not take the risk themselves
- Report and photos after the job for customers, management or authorities
- Tax invoice with 3% withholding tax for companies and agencies
Ozone Treatment for Closed Rooms and Stuffy Spaces
The World Health Disinfection ozone treatment service uses machines that generate ozone gas from oxygen in the air. It suits closed rooms such as meeting rooms, bedrooms, classrooms, sick bays and vans, helping reduce germs in the air and on surfaces and removing stale odours. Ozone breaks back down into oxygen after treatment, leaving no residue.
- Works alongside disinfection fogging: spray or wipe surfaces first, then use ozone for the air and corners of closed rooms
- No people or pets in the room during treatment: the team seals the room and runs a timer
- Ventilate after treatment before normal use resumes
- Machines tested by Intertek, according to WHD's service page
- Ideal after someone has been ill, such as recovered patients' rooms, shared bedrooms and shuttle vans
Before and After
Frequently Asked Questions
Q: How many school outbreaks did Hong Kong have? A: The CHP recorded 602 from the start of term to late October 2025, against 88 in the whole previous winter season.
Q: Should schools close when children fall ill? A: Hong Kong experts said closure was not yet needed, but screening and keeping sick children home were key. In Thailand, consult local health officials.
Q: Does the fogging disinfectant work on flu? A: The team uses Chemgene HLD4H, which meets EN 14476 for virucidal activity according to the product page, and influenza is an enveloped virus that suitable disinfectants can inactivate. Fogging does not replace vaccination or handwashing.
Q: Can I enter the room right after ozone treatment? A: No one should be in the room during treatment. Ventilate afterwards before normal use; the team will advise the right time for the room size.
Q: Can schools get a tax invoice? A: Yes. Tax invoices are issued and 3% withholding tax is supported. Call 065-556-6294 or LINE @whd268.
Related Links and Sources
Prevent Flu with Disinfection Fogging and Ozone Treatment
The true story from Hong Kong shows flu can sweep through schools very quickly. Prepared primary schools cut absences and class closures. Reduce the risk with the World Health Disinfection disinfection service for classrooms, canteens and restrooms, and the ozone treatment service for sick bays and air-conditioned classrooms. To book, call 065-556-6294 or LINE @whd268.
Keywords: school flu outbreak, Hong Kong flu, primary school flu, class closure flu, school disinfection, classroom ozone treatment
