An unusual and early outbreak of influenza A has been detected in Denmark, with a significant number of cases linked to the recent Smukfest music festival in Skanderborg. The Statens Serum Institut (SSI) reports that this is the first time in 15 years of monitoring that such an early influenza outbreak has been recorded in the country.

The SSI describes the situation as “atypical” in their latest weekly update on respiratory diseases.

A spike in influenza A cases has been observed nationally. In week 33, the number of cases rose to 115, a sharp increase from the 19 cases reported the previous week.

A number of these cases can be traced back to Smukfest, which took place from August 3rd to 10th. According to Ramona Trebbien, section leader at the Statens Serum Institut, those infected with the identical virus had attended the festival, suggesting a strong link between the event and the outbreak. Other cases had a different source of infection.

Influenza typically causes major infections during the winter months. The SSI is closely monitoring the development of this early outbreak, which is considered highly unusual for August.