Chancellor Angela Merkel has raised concern over the rising number of coronavirus infections in Germany and the resurgence of what she called a "certain recklessness" among people.

Increasing numbers of hospital admissions with COVID-19 "worry me a great deal," Merkel told the Sunday edition of the Frankfurter Allgemeine Zeitung.

"It should be a concern for all of us," the chancellor said.

The outgoing chancellor was also "very sad" that nearly 3 million Germans above the age of 60 have still not had the shot.

"But the fact that, for example, 2 or 3 million Germans over 60 are still unvaccinated makes me very sad, because that could make a difference for them personally as well as for society as a whole," she said.

The virus caseload in Germany has seen an uptick with the onset of autumn. Germany has not made it mandatory for any groups to get vaccinated against the coronavirus.

The Robert Koch Institute (RKI) on Saturday recorded 21,543 new cases and 90 deaths in the last 24 hours.

The country's seven-day coronavirus incidence rate exceeded 145 infections per 100,000 people on Saturday, after reaching 100 last week for the first time since May.

dvv/sms (AFP, dpa)