LONDON — Even as governments around the world struggle to contain the coronavirus pandemic, many officials are themselves falling victim to the pathogen, undermining global efforts to address the crisis.
Prime Minister Justin Trudeau of Canada put himself in isolation after his wife tested positive, and a number of other senior officials from Britain to Iran to Australia were confirmed to be infected. President Jair Bolsonaro of Brazil said on Friday that he tested negative, after one of his aides tested positive.
There is, though, rising concern that President Donald Trump and members of his staff and cabinet might have been exposed in meetings with different officials from overseas, including with Mr. Bolsonaro’s aide.
In a closely connected political world where officials crisscross the globe as they take part in frequent meetings with heads of state and other policymakers, the cases vividly illustrate how no one is immune from a virus that does not distinguish between the powerful and everyone else.
The exposures follow what has already been a troubled, inconsistent and sometimes chaotic response by many governments around the world.
“It doesn’t matter if you are the leader of one of the greatest democracy in the world or not, you too can get the coronavirus,” Dr. Leslie Vinjamuri, the director of the U.S. and Americas Program at the Chatham House research group in London.
The risk is that entire cabinets or senior government officials could be sidelined at once, potentially undermining an already complex response.
“Any number of cabinets are going to be having endless meetings where they are going to be discussing these scenarios and coming up with plans in real time,” she said.
Mr. Bolsonaro was a guest of Mr. Trump at the Mar-a-Lago resort in Florida last weekend, along with an entourage including his press secretary, who later tested positive. Mr. Bolsonaro posted on Twitter that he had tested negative for the virus, a short time after some local news outlets reported the opposite.
In Canada, Sophie Grégoire Trudeau, Mr. Trudeau’s wife, tested positive for the virus on Thursday after becoming mildly ill. Last week she had traveled to Britain with her daughter and with Margaret Trudeau, the prime minister’s mother, to take part in a charity event. She was part of a panel with Julia Gillard, the former Australian prime minister.
Mr. Trudeau will remain in isolation for the next two weeks, his office said in a statement, as will some members of his cabinet. Because he has not been out of the country recently and displays no symptoms, Canadian doctors followed current medical protocols and have not tested the prime minister.
Several other Canadian politicians who feel ill, including members of his cabinet and Jagmeet Singh, the leader of an opposition party, have also voluntarily quarantined themselves.
On Friday, lawmakers voted unanimously to suspend Parliament in Canada until April 20.
Australia’s minister for home affairs, Peter Dutton, announced on Friday that he had tested positive for the virus.
He had woken up with a fever and a sore throat just a week after he met with Attorney General William P. Barr, Ivanka Trump and senior security officials from the so-called “five eyes” alliance of the United States, the United Kingdom, Canada and New Zealand.
Only a week ago, Mr. Dutton, a hard-line conservative and former police officer, thought nothing of promoting the series of meetings on Twitter.
He posted a photo of himself standing at a podium in front of Mr. Barr, and the Australian embassy in the United States later posted a photo on Twitter showing Mr. Dutton alongside Ms. Trump.
On Friday, after the announcement was made, the gathering took on a more ominous tone.
Mr. Dutton tried to downplay his illness. “I feel fine and will provide an update in due course,” he said, though noted that he had been admitted to the hospital, as is policy in Australia.
But his travel and subsequent meetings with Prime Minister Scott Morrison of Australia and other cabinet officials have thrust the virus into an insular circle of government elites, where handshakes and close conversation is the norm, and youth is rare. The virus is more dangerous for older people.
Fabio Wajngarten, Mr. Bolsonaro’s press secretary and part of his entourage in Florida last week, came into contact with Mr. Trump during that time. A photo posted to his Instagram account showed him standing alongside the president, wearing a “Make Brazil Great Again” hat.
The White House said on Thursday that Mr. Trump and Vice President Mike Pence, who also attended the meeting and is seen in the photograph, did not intend to get tested or go into quarantine.
When asked about the contact he had with the Brazilian delegation, Mr. Trump said, “I’m not concerned.”
Human-to-human transmission of the virus happens when infected people produce tiny respiratory droplets as they breathe, talk, cough or sneeze, allowing the virus to travel through the air. While most of these droplets fall to the ground, people who are in close contact with those infected may catch the virus this way.
Studies have found that even those infected by the virus who are experiencing few symptoms can pass the virus on to others.
Dr. Vinjamuri of the research organization in London said the potential for leaders to contract the virus could also drive home the gravity of the situation.
“In some ways, when it’s one of our world’s leaders — whether it’s Trudeau or a cabinet minister or a health secretary or a health minister, I think it resonates with people,” she said. “It sort of shows them no one is invincible.”
Elsewhere across the world, as the virus has spread more widely through populations, numerous government officials and prominent leaders have become infected.
In Italy, where there is a nationwide lockdown and where cases have risen to more than 15,000, Nicola Zingaretti, the leader of the governing coalition’s Democratic Party, said he had tested positive last week. Some members of that country’s Parliament have been quarantined.
Spain’s equality minister, Irene Montero, and the leader of the far-right opposition party Vox, Santiago Abascal, and his deputy, Javier Ortega Smith, all tested positive for the virus. Other members of that party were self-isolating, and the country decided to halt the meeting of the country’s parliament.
At least eight lawmakers in Spain have tested positive.
Nadine Dorries, Britain’s health minister, has tested positive for the virus. She attended a reception with Prime Minister Boris Johnson and his fiancé, Carrie Symonds, in Downing Street last week. Mr. Johnson said he would not be tested for the virus.
Another British cabinet minister, Anne-Marie Trevelyan, the international development secretary, came into close contact with Ms. Dorries, and was self-isolating. Her initial test for the virus came back negative, a spokesperson told the Independent newspaper. She was among at least four British lawmakers taking similar precautions.
Several of Iran’s senior government officials, including the deputy health minister, have also been found to have the virus. Two vice presidents, several ministers and dozens of parliament members were among the infected.
Iranian state media also reported that Mohammad Mirmohammadi, 71, a member of the Expediency Council, which advises Iran’s supreme leader, had died from the virus.
It was unclear how recently the adviser had been in contact with the supreme leader, Ayatollah Ali Khamenei, 80.
Megan Specia reported from London and Damien Cave from Sydney. Ian Austen contributed reporting from Ottawa and Ernesto Londoño from Buenos Aires.