BRUSSELS, Nov 26 (Reuters) - Belgium detected Europe's first confirmed case of the new variant of COVID-19 on Friday (Nov 26), and at the same time announced measures aimed at curbing a rapidly spreading fourth wave of coronavirus infections.

Health Minister Frank Vandenbroucke told a news conference that a case of variant B.1.1.529 had been found in an unvaccinated person who had developed symptoms and tested positive on Nov. 22.

"It is a suspicious variant. We do not know if it is a very dangerous variant," he said.

The new coronavirus variant, first detected in South Africa, has caused global alarm, with the EU and Britain among those tightening border controls as researchers seek to find out if the mutation is vaccine-resistant.

Belgium's national reference laboratory said the infected person was a young adult woman who had developed symptoms 11 days after returning from a trip to Egypt via Turkey. She had flu-like symptoms, but no signs to date of severe disease.

None of her household members developed symptoms, but were being tested.

The new variant has emerged as Belgium and many other European countries are battling a surge in coronavirus infections.

Belgian Prime Minister Alexander De Croo announced that nightclubs would close and bars and restaurants would have to shut by 11pm for three weeks from Saturday, and have a maximum six people per table.

The strain on the health service was mounting, De Croo told a news conference, adding,"If we did not have such a high rate of vaccination today, we would be in an absolutely drastic situation".

A previous package of coronavirus restrictions imposed a week ago included enforcing wider use of masks and more working from home.

Under the new rules, private parties and gatherings are also banned, unless they are for weddings or funerals, and Belgians will have to do shopping on their own.

The country's health ministers will meet on Saturday to discuss accelerating the roll-out of vaccine booster doses.

Belgium, home to European Union institutions and the headquarters of NATO, has the sixth-highest number of cases per capita rate in Europe, behind the likes of Austria and Slovakia that have re-entered lockdowns.

The fatality rate though is just below the EU average, with 75 per cent of the population vaccinated against COVID-19.