BERLIN — Polish President Andrzej Duda has tested positive for the novel coronavirus, his spokesman announced on Saturday, the latest in a string of world leaders to be infected.

Duda is doing “fine,” Blazej Spychalski, secretary of state in the president’s chancellery, posted on Twitter.

“We are in constant contact with the relevant medical services,” he added.

The 48-year-old president, an ally of the ruling populist Law and Justice party, narrowly won reelection in a tightly fought race in July. While his role is largely ceremonial, the president has the power to veto laws and plays a part in formulating foreign policy.

Duda’s positive test comes as Poland, like much of Europe, faces a surge in coronavirus cases. The entirety of the country was classed domestically as a “red zone” as of Saturday, putting all its 40 million citizens under the highest level of restrictions. Bars and restaurants have been instructed to close.

Poland reported more than 13,600 new cases on Friday, with the number of infections doubling in less than three weeks.

Health authorities across the continent have been warning of a dangerous rise in infections since August.

Most European countries have a “highly concerning epidemiological situation,” Andrea Ammon, the director of the European Centre for Disease Prevention and Control, said on Friday. Action is needed to avoid health-care systems being overwhelmed, she said.

In neighboring Germany, Health Minister Jens Spahn also tested positive for the coronavirus this week, with his ministry saying he was experiencing cold-like symptoms. Meanwhile, Belgian Foreign Minister Sophie Wilmès was admitted to intensive care.

In addition to President Trump, British Prime Minister Boris Johnson, Brazilian President Jair Bolsonaro and Belarus President Alexander Lukashenko are among other world leaders to have contracted the virus.