Odense Municipality confirmed the closure in a statement on Monday after informing parents and pupils on Sunday evening.
The Danish Patient Safety Authority (Styrelsen for Patientsikkerhed) said on Monday morning that the case is suspected of being linked to the new Omicron variant.
The authority recommends contact tracing up to “third” contacts, or people who have been in contact with suspected close contacts to the confirmed or “first” case.
Pupils and teachers in the same class as the confirmed or “first” case are considered “second” contacts, with close contacts to the class the “third” link.
People who fall into these categories are asked to isolate at home until they have tested negative on the fourth and sixth days since the potential contact.
The school is closed as of Monday while contact tracing is undertaken.
On Monday, the World Health Organization said the new Covid-19 Omicron variant poses a “very high” risk globally and stressed that uncertainties remained about how contagious and dangerous the strain was.
“If another major surge of Covid-19 takes place driven by Omicron, consequences may be severe,” WHO said in a technical note, adding though that “to date, no deaths linked to Omicron variant have been reported.”