BERLIN • A spike of more than 1,500 coronavirus infections within days has dealt a sudden blow to Germany's efforts to reopen the country, calling into question the durability of what had been widely considered a success story in managing the outbreak in Europe.
The new clusters have been concentrated in slaughterhouses and crowded, low-income apartment blocks, which have been quarantined, but they are generating increasing concern that the infections could break out and spread among the broader public.
This week, the authorities in the state of North Rhine-Westphalia imposed lockdowns in two counties - the first since the country's broader reopening last month - after hundreds of workers at the Tonnies meatpacking plant in Gutersloh county tested positive for the coronavirus.
Neighbouring Warendorf county, where many plant workers live, was also locked down.
The outbreak at the slaughterhouse now stands as one of the most severe in Europe, outside of Sweden, according to figures gathered by the European Union.
Since then, several hundred workers from two other slaughterhouses have been isolated as well.
Hundreds of police and health workers have fanned out over the region during the past week in an effort to find and test all of the Tonnies plant's 7,000 workers - many of them seasonal labourers from Eastern Europe who were not properly registered with the authorities, raising fears that it might be hard to contain the outbreaks with a targeted approach.
Nationwide, the health authorities registered 630 new cases on Thursday - hundreds more than the daily total just 10 days ago.
The Robert Koch Institute said the number of new cases rose by more than a quarter in much of the country over the past week, spreading rapidly in states that had experienced an outbreak.
The number of cases and the tenacity of the virus are now challenging an approach that had made Germany a model for European states looking to return to a semblance of normal life.
When the virus first began spreading rapidly in early March, Chancellor Angela Merkel overcame the obstacles of Germany's decentralised federal system, forging consensus among the governors of the country's 16 states to impose one of the strictest lockdowns in Europe.
But several weeks later, with the number of new infections dropping and people itching to get out, the governors grew restless too.
The country's opening has been accompanied by a rise in cases - so far manageable but increasingly concerning. Germany has reported over 193,000 infections, with over 9,000 deaths.
"The numbers are going up in almost all German states," lawmaker Karl Lauterbach wrote on Twitter. "It may be that we have already gone too far with the easing" of curbs.
Despite the flare-up, the pandemic is subsiding in Europe, World Health Organisation chief Tedros Adhanom Ghebreyesus said on Thursday.
Speaking with members of the European Parliament's health committee, Dr Tedros also said that once the pandemic was over, the world should not return to its previous state, but build a "new normal" that would be fairer, greener and help prevent climate change.