Germany's Robert Koch Institute (RKI) for disease control on Wednesday reported 1,226 new cases within 24 hours. The last time infections were higher was on May 9th when 1,251 new cases were registered.

Health Minister Jens Spahn has called the development “undoubtedly worrying”.

The peak in the number of new infections reported daily was at the beginning of April when there were more than 6,000 cases.

The number fell in May, but has been rising again since the end of July. Experts are concerned there could be a sharp increase in the number of cases, which would push health authorities to their limits in tracking chains of infection.

Spahn said the rise in cases was a warning sign. “This is undoubtedly worrying,” the Christian Democrat (CDU) politician said on Wednesday during an interview on Deutschlandfunk radio.

“Here we see that due to the return of travel, but also due to parties of all kinds, due to family celebrations in many places in the country, we have small and large outbreaks in almost all regions of the country.

“And of course, if we don't all pay attention to each other now, this can create a dynamic.”

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Spahn said everyone in Germany must remain alert. RKI head Lothar Wieler has also warned against carelessness, which causes rising infection rates.

The current infections are spread across the country rather than the hotspots we've seen in the previous two months, such as the Tönnies meat processing plant outbreak earlier in the summer. This development makes it trickier to trace infection chains and stamp out the virus.

Since the beginning of the coronavirus crisis, at least 218,519 people in Germany have contracted the Sars-CoV-2 virus, the RKI reported on Wednesday morning.

Since the previous day, six new deaths have been reported. According to RKI, the number of deaths stands at 9,207. Around 198,800 people have survived coronavirus in Germany, according to estimates.

Spahn said the health care system is well able to cope with the current infection numbers. But with every new infection, it would become more difficult for the health authorities.

READ ALSO: Is Germany heading for a second lockdown amid rise in coronavirus cases?

Renewed appeal to stick to the rules

Spahn again appealed to citizens to observe the rules of hygiene, wear masks, keep their distance and maintain the setting at events.

He was sceptical about the prospects for major events. They are currently banned in Germany until the end of October.

“Whether it's football matches, whether it's other major events, that's something where I continue to be very cautious, because these are of course the very events that have a symbolic effect on the smaller ones,” he said.

On Wednesday some 2.5 million children were returning to 5,500 schools in North Rhine-Westphalia, Germany's most populous state.

The country is watching this development closely because in this densely populated state, it could become particularly clear how health and protection concepts in schools are working.

But President of the Medical Council, Klaus Reinhardt, spoke out against closing entire schools in case of individual coronavirus infections.

“If a corona case occurs in a school, the school does not have to be closed directly for 14 days,” he told the newspaper Rheinische Post. It would be sufficient if individual classes or courses stayed at home instead, he said.