BERLIN -- German Chancellor Angela Merkel's chief of staff fears the number of new coronavirus cases will soar in the next few weeks and could hit 100,000 a day by the end of September, causing big problems for many businesses, he told Bild am Sonntag weekly.
After more than two months of steady decline, cases have been rising in Europe's biggest economy since early July, due mainly to the spread of the more infectious Delta variant.
Merkel's chief of staff, Helge Braun, told Bild am Sonntag cases were increasing by 60% per week, even though nearly half the population has been fully vaccinated.
"If the Delta variant were to continue to spread at this rate and we don't counter it with a very high vaccination rate or change in behaviour, we would have an incidence of 850 (per 100,000 people) in just nine weeks," he said.
"That would equate to 100,000 new infections a day," he said, adding the effect would be huge as so many people would have to quarantine.
"The impact on work processes in factories would be massive. We are already seeing this in the UK," he said.
The number of cases has risen by 1,387 in the last day to 3.76 million, the Robert Koch Institute for infectious diseases said on Sunday, with the 7-day incidence inching up to 13.8 per 100,000 people.
Braun urged Germans to get vaccinated. Around 60% of Germany's 83 million people have had a first shot and about 48% are fully vaccinated.
While Germany has made clear it will not force people to get vaccinated, Braun said those who refused would have to face some restrictions.
"This could mean some things such as restaurant, cinema and stadium visits would not be possible for tested unvaccinated people because the residual risk is too high," he said, adding, however, that a full lockdown would probably not be needed.
Some 91,524 people have died of COVID-19 related causes in Germany.