BERLIN -- The head of Germany's disease control agency warned Friday that a decline in new coronavirus infections the country saw has levelled off while the share of cases involving more contagious variants is rising.

Robert Koch Institute President Lothar Wieler said Germany may be heading toward another "turning point" in the pandemic after weeks of falling infections.

"The decline of recent weeks doesn't appear to be continuing," Wieler told reporters in Berlin, noting that in one German state -- Thuringia -- weekly case numbers are on the rise again.

His agency reported 9,113 new COVID-19 infections in the past day, and 508 more virus-related deaths. Germany has recorded almost 2.4 million confirmed infections and 67,206 deaths from the coronavirus since the start of the pandemic.

The number of new infections reported each week per 100,000 inhabitants has fallen to just under 57.

Dozens of counties have posted infection rates below 35 per 100,000, which the government has said is the level at which certain lockdown measures could be lifted.

But no German state as a whole has achieved that threshold. Thuringia's rate currently stands at almost 117 new cases per 100,000 inhabitants in a week.

The trend comes as several German states prepare to reopen elementary schools and kindergartens next week, a move criticized by some teachers' unions that say there are insufficient measures to protect students and staff members.

Wieler stressed that the hygiene policies developed for schools need to be put into practice.

"We have about 8 million students in Germany and almost 700,000 teachers," he said. "The safety plans that exist...must be implemented. That's the precondition for opening elementary schools and kindergartens."

German Health Minister Jens Spahn expressed concern about the rising share of more contagious virus variants among known infections.

Earlier this week, he said the variant first detected in Britain accounts for 22 per cent of the cases in Germany, up from 6 per cent two weeks ago.

Spahn told reporters in Berlin on Friday that the government wants to double the number of vaccinations in the coming weeks, from about 140,000 per day at present.

Germany has administered almost 3 million first doses since late December. More than 1.5 million people have received their second shot.

Spahn confirmed a report by weekly news magazine Der Spiegel that the government has appointed a special adviser for vaccine production to co-ordinate with manufacturers and speed up the delivery of additional doses to Germany.

Markus Soeder, the governor of Bavaria, said Friday that higher rates of vaccination would give officials greater certainty when deciding whether to further loosen the country's lockdown, which is currently scheduled to continue until at least March 7.

Soeder, who has been mentioned as a possible successor to Chancellor Angela Merkel, cautioned against relaxing restrictions too soon.

"What we do shouldn't result in us having to reverse everything again in three weeks and start from scratch," he told reporters after a video call with Merkel and regional officials. "Better to follow a wise path than have another wave (of infections)."