A sudden outbreak of norovirus, commonly known as winter vomiting disease, has affected over 100 children and at least ten teachers at Skärgårdsskolan in Holmsund, near Umeå, Sweden.

The rapid spread of the virus, which is unusual in such numbers, is suspected to have been transmitted through the school's food services.

In response, the school has implemented measures such as increased adult supervision during meal times and enhanced cleaning protocols.

Despite the outbreak, Umeå municipality is hosting a large event at the local swimming pool, trusting attendees to be symptom-free.

Norovirus is highly contagious, with symptoms including nausea, vomiting, and diarrhea, typically resolving within a few days.

Health officials advise thorough handwashing to prevent further spread.