Several more municipalities are also likely to reach the limit, according to the national infectious disease agency State Serum Institute (SSI).
The incidence rate at which local authorities are asked to take measures aimed at reducing transmissions is 400 cases per 100,000 residents during the last seven days.
A minimum of 20 infections in the last seven days is also required, ensuring municipalities with small populations are not affected if they have very low case numbers but hit the threshold because of a low number of residents.
Measures which local authorities can introduce include keeping school classes separated at break times and cancelling larger school events.
Parents can also be asked to ensure they collect children from daycare outside.
Aarhus Municipality, which hit the 400 cases per 100,000 resident-threshold on Tuesday, is among municipalities to have implemented measures at schools and child care facilities.
The municipality’s leader of its Children & Youth and Health & Well-being sections, May-Britt Kullberg, told local broadcaster TV2 Østjylland all recommendations will be followed where possible in an effort to put the brakes on infection numbers.
“A lot of this was also done by schools and daycare institutions last year. But they definitely had longer to prepare last year. It’s come a bit faster this time,” Kullberg said.
Measures will be introduced in Aarhus once the various municipal services are ready to implement them, according to the report.