LONDON — Once again, the world shuddered at news about President Trump. This time, it wasn’t something Mr. Trump said or did, but rather the announcement that he had tested positive for the coronavirus.
Mr. Trump is not the first world leader to be infected. Prime Minister Boris Johnson of Britain and President Jair Bolsonaro of Brazil both tested positive. Mr. Johnson ended up in an intensive care unit where, he said later, “things could have gone either way.”
But Mr. Trump, 74, is older and at higher risk than either of those men. The news of an American president contracting a potentially lethal virus carried global repercussions beyond that of any other world leader. Financial markets fell in Asia and looked set to open lower in Europe and the United States.
Expressions of concern and good wishes for Mr. Trump’s speedy recovery — as well as that of the first lady, Melania Trump — poured in from officials in India, Britain and other countries.
“Wishing my friend @POTUS @realDonaldTrump and @FLOTUS a quick recovery and good health,” the prime minister of India, Narendra Modi, said in a tweet.
Taiwan’s Foreign Ministry said on Twitter: “Our best wishes to @realDonaldTrump & @FLOTUS for a speedy recovery & return to full health. The government & people of Taiwan stand with the U.S. at this testing time.”
Britain’s housing secretary, Robert Jenrick, said on Sky News, “All of us want to send our best wishes to President Trump, the first lady and the Trump family and wish them a speedy recovery.”
He added, “We know what it’s like to have, in our case a prime minister who tested positive for Covid and setting aside politics we all want to see him and his wife get better soon.”
Some commentators noted that it was a grim reminder of a virus that didn’t distinguish between rich or poor, weak or powerful.
The United Nations Office for Disaster Risk Reduction tweeted, “Nobody is immune from #COVID19.”
In Myanmar, a Baptist minister who met with Mr. Trump in the Oval Office last year and told him about oppression and torture by the military, said that having Covid-19 could help the president better understand the pain of others.
“There are many critics of Trump regarding Covid-19,” said the minister, Hkalam Samson. “Now he is suffering himself and he should be compassionate for his people by now.”
Others saw a degree of justice in his diagnosis, given his record of diminishing the threat of the virus, refusing simple precautions like wearing a mask and holding campaign rallies without little to no social distancing. During the presidential debate on Tuesday, he mocked former Vice President Joseph R. Biden Jr. for wearing a mask.
“When the president of the United States, the most powerful person in the world, can catch this, the virus has no boundaries,” said Wang Huiyao, the founder and president of the Center for China and Globalization, an influential research group in Beijing.
Mr. Wang said that the president’s positive test result might become a global reminder of the value of wearing face masks, which are still widely worn in mainland China even though it has not reported a locally transmitted case in more than six weeks.
“He has also had large crowds, shaking hands and greeting people, and he seldom wears a mask,” Mr. Wang said. “He probably serves as a good reminder to the whole world that, as U.S. experts have said, it is important to wear a mask.”
In China, the news sparked an online firestorm, and within an hour had rocketed to the top of the most-searched topics on Sina Weibo, a popular though heavily censored social media platform. The commentary reflected a mix of sympathy, disbelief and even glee from some online users who saw the development as just retribution for Mr. Trump, who is widely seen in China as having spearheaded the recent downward spiral in relations between the United States and China.
“The whole world rejoices!” read one comment on Sina Weibo that had been liked 55,000 times in the hour after it was posted.
Hu Xijin, the chief editor of The Global Times, a nationalist Chinese state-owned tabloid, put it in brash terms.
“President Trump and the first lady have paid the price for his gamble to play down the COVID-19. The news shows the severity of the US’ pandemic situation,” Mr. Hu tweeted. “It will impose a negative impact on the image of Trump and the US, and may also negatively affect his reelection.”
Others took the opportunity to ridicule Mr. Trump.
“Covid, stand back and stand by,” wrote Raphael Bob-Waksberg, an American comedian, in a viral tweet, referring to comments made by the president about a far-right militant group.
Radoslaw Sikorski, a former Polish foreign minister who is now a member of the European Parliament, wrote on Twitter, “Mr. President @realDonaldTrump, I suggest you do not try to treat yourself with bleach.”
Mark Landler reported from London, and Mike Ives from Hong Kong. Reporting was contributed by Keith Bradsher and Claire Fu from Beijing; Elaine Yu and Yonette Joseph from Hong Kong; Carlos Tejada from Seoul, South Korea; Amy Qin from Taipei, Taiwan; Steven Erlanger from Brussels; Saw Nang from Mandalay, Myanmar; and Richard C. Paddock from Bangkok, Thailand.
