The True Story: A Repeat Advisory in One Season, the First in Years

On 29 January 2026, the Tokyo Metropolitan Government issued a new flu advisory after suspected flu cases at schools and social welfare facilities passed 6,000 by 25 January, and patients per monitored institution rose to 13.83, above the threshold of 10.

It was the first time since the 2008–2009 season that a new advisory followed a lifted warning in the same season. Officials believed year-end and New Year travel and the reopening of schools contributed, and urged handwashing, disinfection and masks.

The Key Lesson: After a Long Holiday, the Virus Returns with People

Thai student dorms take students back from every region at once after holidays. Points to watch are:

• Shared rooms for 2–4 sleeping close every night
• Shared floor bathrooms used in turn every morning
• Coin laundries and water dispensers everyone touches
• Study and lounge rooms crowded at exam time
• Return from long holidays when students bring infection from home

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 Student Dormitories

1. Sick students sleep in rooms with friends: likelihood high / impact high / level critical. Mitigation: provide a temporary isolation room. Owner: dorm manager
2. Shared bathrooms not cleaned on a schedule: likelihood high / impact medium / level high. Mitigation: clean twice daily and wipe taps. Owner: dorm housekeeper
3. Shared touch points not wiped: likelihood high / impact low / level medium. Mitigation: wipe handles, lift buttons and washers daily. Owner: dorm housekeeper
4. Crowded study rooms at exams: likelihood medium / impact medium / level medium. Mitigation: limit numbers and ventilate. Owner: dorm manager
5. Rooms not disinfected between tenants: likelihood medium / impact medium / level medium. Mitigation: fog and ozone-treat rooms before new tenants. Owner: dorm manager

Ways to Reduce Flu Risk in Student Dorms

1. Ask students with fever to inform dorm staff
2. Provide temporary isolation for sick students
3. Clean shared bathrooms twice daily
4. Wipe shared touch points daily
5. Install hand sanitiser on every floor
6. Fog common areas after long holidays
7. Ozone-treat rooms between tenants or after recovery

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: Why did Tokyo issue a repeat advisory? A: Officials believed New Year travel and school reopening drove cases up again.

Q: What should a sick student do? A: Rest in a separate room, wear a mask outside it, drink plenty of fluids, and see a doctor if breathing is hard or fever persists.

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 dorms or universities 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

The true story from Tokyo shows the return from long holidays is a risky time. Prepared dorms let students study and sit exams without whole floors falling ill. Reduce the risk with the World Health Disinfection disinfection service for shared bathrooms, corridors and common rooms, and the ozone treatment service for student rooms and isolation rooms. To book, call 065-556-6294 or LINE @whd268.

Call 065-556-6294 | LINE: @whd268