News of the infection of the world’s most powerful man with the coronavirus drew instant reactions of shock, sympathy, undisguised glee and, of course, the ever-present outrage and curiosity that follows much of what Donald Trump does.

The US president’s announcement that he and US first lady Melania Trump tested positive for Covid-19 permeated the global news cycle, sparking comment everywhere from presidential offices to the thousands weighing in on social media.

Here is a flavour of some of the reaction:

Stock market

The positive test reading for the leader of the world’s largest economy adds more uncertainty to investors’ worries, including how the infection might affect the November 3 election between Mr Trump and Democratic challenger Joe Biden.

US stock futures and Asian shares fell in the wake of the news. The future contracts for both the S&P 500 and the Dow industrials lost 1.9%. Oil prices also slipped.

Stock prices in Japan and Australia tumbled.

“To say this potentially could be a big deal is an understatement,” financial services firm Rabobank said in a commentary. “Anyway, everything now takes a back seat to the latest incredible twist in this US election campaign.”

World leaders

World leaders and officials were quick to weigh in, and there was both sympathy and something approaching schadenfreude.

Indian prime minister Narendra Modi tweeted: “Wishing my friend @POTUS @realDonaldTrump and @FLOTUS a quick recovery and good health.”

US-India ties have prospered under Mr Trump, and India is seen as a partner to balance China’s growing weight in Asia.

Australian agriculture minister David Littleproud, deputy leader of the conservative Nationals party, told the Australian Broadcasting Corp: “Our best wishes go to the president and the first lady, but it demonstrates that no-one is immune from Covid-19 and catching it. So it shows that no matter the precautions, we are all susceptible to this.

“A trying time, and it just goes to show that a global pandemic can in fact touch anybody, even the president of the United States.”

Tokyo governor Yuriko Koike, speaking at a weekly news conference, did not mention Mr Trump’s reluctance to wear masks when asked about his infection, but she said the news “reminded me of how widely masks are worn in Japan”.

Global media

Major media across the globe also played up the announcement, with bulletins appearing on TV screens in Seoul, Tokyo, Taipei and Beijing.

China’s official Xinhua News Agency and state broadcaster CCTV both announced the news, but there was no immediate comment from the government in Beijing on Friday, the second day of an eight-day national holiday.

The positive test result for Mr Trump and his wife was the most searched topic in China – after news about the holiday – on the popular social media app Weibo a few hours after the announcement, with most comments mocking or critical.

One user darkly joked that Mr Trump had finally tweeted something positive.

The Chinese government has bristled at Mr Trump’s attempts to blame China, where the disease emerged, for the pandemic, and called for global cooperation in fighting it, a message that has resonated with the public.

Hu Xijin, the editor of the state-owned Global Times newspaper, tweeted in English that “President Trump and the first lady have paid the price for his gamble to play down the Covid-19”.

Iranian state television announced Mr Trump had the virus, with an anchor breaking the news alongside an unflattering image of the US president surrounded by what appeared to be giant coronaviruses.

US-Iranian ties have suffered since Mr Trump unilaterally withdrew the United States from Tehran’s nuclear deal with world powers and reimposed crushing sanctions.

Social media

Social media platforms in Asia were ablaze with quick reaction.

While the uncertainty seemed palpable on a scroll through various nations’ social media, many of the comments seemed to revel in the announcement.

“Here comes a chance for him to actually try out his idea of injecting disinfectant into himself and fighting back (against allegations that) it was fake news!” tweeted Hiroyuki Nishimura, a Japanese internet entrepreneur, referring to an idea Mr Trump floated earlier this year for treatment.

Keio University economics professor Masaru Kaneko tweeted that populist leaders, like Prime Minister Boris Johnson and Brazilian president Jair Bolsonaro, “got infected because they tended not to take the coronavirus seriously. The two other leaders seriously tackled (the virus) after they get infected themselves. Will the United States follow their examples?”