The True Story: Flu in Midsummer

A report published via Newswav, citing Denmark's Statens Serum Institut (SSI), said Denmark recorded 115 flu cases from 11 to 17 August 2025, up from 19 the week before, which is highly unusual for summer.

The outbreak was linked to the Smukfest music festival in Skanderborg, attended by about 60,000 people, and the virus found was genetically identical H1N1. Ramona Trebbien of SSI said large crowds in close contact helped the virus spread quickly.

The Key Lesson: Days in a Crowd, Singing and Sleeping in Tents Close Together

Thai outdoor music festivals and camping events are busiest in the cool season, with attendees together for days. Points to watch are:

• Front of stage where people sing packed together
• Shared toilets and showers used all night
• Tents pitched close together
• Food stalls and bars reusing cups
• Artist dressing rooms and crew rooms

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 Outdoor Music Festivals and Campsites

1. Crowded front of stage: likelihood high / impact medium / level high. Mitigation: zone the area and plan crowd flow. Owner: organiser
2. Shared toilets without handwashing: likelihood high / impact medium / level high. Mitigation: handwash points and hourly cleaning. Owner: sanitation team
3. Reused cups not sanitised: likelihood high / impact medium / level high. Mitigation: personal cups or hot-water washing. Owner: bar manager
4. Sick attendees stay on site: likelihood medium / impact high / level high. Mitigation: first-aid point and separate tent for the sick. Owner: event medical team
5. Dressing rooms not disinfected between artists: likelihood medium / impact medium / level medium. Mitigation: fog and ozone-treat dressing rooms daily. Owner: stage manager

Ways to Reduce Flu Risk at Music Festivals

1. Set up handwash points across the site
2. Clean toilets hourly
3. Zone the front of stage
4. Encourage personal cups
5. Provide a separate tent for the sick
6. Announce that feverish people rest and see a doctor
7. Fog and ozone-treat dressing and crew rooms

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 much did Denmark's flu rise after the festival? A: From 19 to 115 cases from 11 to 17 August 2025.

Q: What virus was found? A: Genetically identical H1N1, linked to Smukfest, attended by about 60,000 people.

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 event organisers 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 real news from Denmark shows flu can spread even out of season when tens of thousands gather. Prepared festivals send everyone home with good memories. Reduce the risk with the World Health Disinfection disinfection service for toilets, showers and bar areas, and the ozone treatment service for artist dressing rooms and crew rooms. To book, call 065-556-6294 or LINE @whd268.

Call 065-556-6294 | LINE: @whd268