According to the Robert Koch Institute (RKI), the fourth wave of the corona pandemic has started in Germany.
The proportion of positive samples under the PCR tests in laboratories had risen from four to six percent within a week by mid-August, according to the institute's latest weekly report on Thursday evening.
Younger age groups are particularly affected by infections.
"This clearly shows the beginning of the fourth wave, which is picking up speed, especially due to infections among the young adult population," the report says.
The RKI continues to rate the risk to the health of people who have not yet been vaccinated or who have only been vaccinated once in Germany as high overall.
For fully vaccinated people, the researchers rate it as moderate.
According to the analysis, there has been an increase in the incidence in Germany since the beginning of July, especially in the age groups between 10 and 49 years of age.
A similar increase in this population group was observed in summer 2020 - but only five weeks later, i.e. from the end of September to the beginning of October.
At that time there was no vaccination protection.
So far this summer, the more contagious Delta variant has dominated - now 99 percent.
The incidence in Germany on Thursday was around 44 cases per 100,000 inhabitants - but with strong regional fluctuations.
In total, 63.7 percent of the population received at least one vaccination against Covid-19.
58.2 percent have already been completely immunized against the SARS-CoV-2 virus.
The RKI's weekly report appears with a time delay. Most of the results in the most recent analysis relate to data from the first week of August.