An outbreak of coronavirus in a restaurant in the northern German town of Leer has cast doubt on the effectiveness of the strategy to reopen gastronomy venues in Germany under strict hygiene measures.

The federal state of Lower Saxony, where Leer is located, was the first to allow the reopening of restaurants with restrictions on the number of customers per table and with distance rules between the different tables on the premises.

During a week in Leer there had been no new case of coronavirus contagion.

Now the cases of seven people have been announced, all of them allegedly infected in a restaurant. Fifty other people have had to go into preventive quarantine.

“It is an outbreak with various infections and many contacts,” the Leer Health Office said in a statement, which it believes cannot be discussed in an isolated case.

The seven cases, which are related to each other, were reported between Tuesday and Friday and it is not easy to follow the chain of contacts.

Leer district chief Mathias Grotte said “the outbreak clearly shows us that the coronavirus is still present,” the EFE news agency reported.

Grotte added that it is expected that the cases of people who have to go into quarantine will have extreme growth in the coming days.

A spokeswoman for the Federation of German Hotels and Restaurants (Dehoga) said in statements to Lower Saxony public radio, NDR1, that contagion should not be possible with the hygiene plan in place.

It is currently being examined whether in the restaurant in Leer customers or staff did not respect some of the hygiene rules.

Some experts had warned against visiting closed premises and, for example, the director of the Virology Department of the University of Rostock, in the east of the country, Andreas Podbielski, had been in favor of attending only on the terraces.

Restaurants and bars were closed in Germany in mid-March in the fight against the coronavirus.

Lower Saxony was one of the first federated states to allow the reopening, and premises in that state have been open since May 11.