Delta COVID-19 variant spreading fast in Germany, says government agency

"It is really not a question of whether Delta will become the leading variant, but just when," Wieler warned. "It depends very much on the vaccination rates, and on how we deal with the relaxation of restrictions."

Germany's incidence rate of COVID-19 cases in the past seven days fell from 12 per 100,000 population on Thursday to 10.3 on Friday, according to the RKI, the federal government agency and research institute responsible for disease control and prevention. A week ago, the country's seven-day incidence rate still stood at 19.

If people in Germany remain cautious despite the falling case rates, it could be a "good summer," Germany's federal Health Minister Jens Spahn said at the press conference. However, if the seven-day incidence rate rises again, the response should be swift, with regional rollbacks of relaxations.

The number of new daily COVID-19 infections decreased as well as 1,076 new cases were registered in Germany on Friday, 1,364 less than one week ago, according to the RKI.

As of Thursday, almost 24.7 million people in Germany had been fully vaccinated, bringing the country's vaccination rate to 29.6 percent, the RKI said. Almost 42 million people have received at least one COVID-19 vaccine dose.