Although the share of the Covid-19 Delta variant in Germany is only 6 per cent of the new cases, the strain is spreading at a fast pace, Lothar Wieler, president of the Robert Koch Institute (RKI), said.
"It is really not a question of whether Delta will become the leading variant, but just when," Wieler told reporters here on Friday. "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, reports Xinhua news agency.
If people in Germany remain cautious despite the falling case rates, it could be a "good summer", Health Minister Jens Spahn told reporters. However, if the seven-day incidence rate rises again, the response should be swift, with regional rollbacks of relaxations, he added.
The number of new daily Covid infections decreased as well as 1,076 new cases were registered on Friday, 1,364 less than one week ago, according to the RKI. Germany's overall infection tally currently stood at 3,728,601, while the death toll was 90,277.
Meanwhile, almost 24.7 million people in Germany had been fully vaccinated, bringing the country's inoculation rate to 29.6 per cent, the RKI said. Almost 42 million people have received at least one Covid vaccine dose.