The True Story: South Korea Enters Flu Season Early

Asia Economy reported on 3 November 2025 that the Korea Disease Control and Prevention Agency (KDCA) found suspected flu in week 43 at 13.6 per 1,000 outpatients, 3.5 times last year, highest among children aged 7 to 12 at 31.6 per 1,000. There were 98 inpatients, 7.5 times the previous year, and H3N2 dominated.

Hong Jeongik, director of the Infectious Disease Policy Bureau, said the season started about two months earlier than last year, and KDCA Commissioner Im Seungkwan urged at-risk groups to get vaccinated early.

The Key Lesson: Small Rooms, Shared Equipment, Primary-Age Children

Children's language, music and art schools in Thailand use small rooms with instruments, keyboards and equipment that many children use in turn.

• Primary-age children are often ill and are the core customers of enrichment schools
• Never share wind instruments, and clean other equipment every time
• Small rooms have little airflow, so leave gaps between classes
• The season can come months early; do not rely on the usual calendar
• Offer make-up or online lessons when children are ill

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 Children's Language and Music Schools

1. Sick children attending in small rooms: likelihood high / impact high / level critical. Mitigation: Make-up and online classes, plus classroom fogging. Owner: School owner
2. Shared piano keys, drums and equipment: likelihood high / impact medium / level high. Mitigation: Disinfect after every class. Owner: Teachers
3. Stuffy small classrooms: likelihood medium / impact medium / level medium. Mitigation: Ventilation breaks and ozone after closing. Owner: Branch manager
4. Sick teachers cancelling many classes: likelihood medium / impact high / level high. Mitigation: Backup teachers and teacher vaccination. Owner: Academic office
5. Crowded parent waiting areas: likelihood medium / impact low / level low. Mitigation: Limit waiting and wipe seats. Owner: Front desk

7 Steps to Prevent Flu in Children's Enrichment Schools

1. Announce free make-up lessons for sick children
2. Stop sharing wind instruments; children use their own
3. Wipe piano keys, desks and equipment after every class
4. Leave 10 minutes between classes with doors open
5. Fog every classroom weekly in flu season
6. Ozone-treat classrooms and practice rooms after closing
7. Tell parents about vaccination for children as advised by doctors

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: Does fogging affect musical instruments? A: Tell the team so they can assess and plan fogging suited to rooms with instruments.

Q: Can music practice rooms be ozone-treated? A: Yes, when empty, with ventilation before use.

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 an enrichment school 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

• World Health Disinfection disinfection service
• World Health Disinfection ozone treatment service
• Chemgene HLD4H disinfectant and price
• Influenza information from Thailand's Department of Disease Control, hotline 1422
• WHO seasonal influenza fact sheet

Prevent Flu with Disinfection Fogging and Ozone Treatment

South Korea shows flu can arrive two months early and hit primary-age children hardest, so children's schools must prepare in advance. Reduce the risk with the World Health Disinfection disinfection service for classrooms, waiting areas and corridors, and the ozone treatment service for music practice rooms and small classrooms. To book, call 065-556-6294 or LINE @whd268.

Call 065-556-6294 | LINE: @whd268