Donald Trump was reportedly taken to underground bunker during White House protests

Washington, Apr 28: After nearly three weeks in an intensive care unit in Los Angeles, doctors treating 41-year-old Broadway actor Nick Cordero for COVID-19 were forced to amputate his right leg.

The flow of blood had been impeded by a blood clot: yet another dangerous complication of the disease that has been bubbling up in frontline reports from China, Europe and the United States.

To be sure, so-called "thrombotic events" occur for a variety of reasons among intensive care patients, but the rates among COVID-19 patients are far higher than would be otherwise expected.

"I have had 40-year-olds in my ICU who have clots in their fingers that look like they'll lose the finger, but there's no other reason to lose the finger than the virus," Shari Brosnahan, a critical care doctor at NYU Langone said.

One of these patients is suffering from a lack of blood flow to both feet and both hands, and she predicts an amputation may be necessary, or the blood vessels may get so damaged that an extremity could drop off by itself.

Blood clots aren't just dangerous for our limbs, but can make their way to the lungs, heart or brain, where they may cause lethal pulmonary embolisms, heart attacks, and strokes.

A recent paper from the Netherlands in the journal Thrombosis Research found that 31 percent of 184 patients suffered thrombotic complications, a figure that the researchers called "remarkably high" -- even if extreme consequences like amputation are rare.

Behnood Bikdeli, a doctor at New York-Presbyterian Hospital, assembled an international consortium of experts to study the issue. Their findings were published in the Journal of The American College of Cardiology.

The experts found the risks were so great that COVID-19 patients "may need to receive blood thinners, preventively, prophylactically," even before imaging tests are ordered, said Bikdeli.

What exactly is causing it? The reasons aren't fully understood, but he offered several possible explanations.

People with severe forms of COVID-19 often have underlying medical conditions like heart or lung disease -- which are themselves linked to higher rates of clotting.

Next, being in intensive care makes a person likelier to develop a clot because they are staying still for so long. That's why for example people are encouraged to stretch and move around on long haul flights.

It's also now clear the COVID-19 illness is associated with an abnormal immune reaction called "cytokine storm" -- and some research has indicated this too is linked to higher rates of clotting.

There could also be something about the virus itself that is causing coagulation, which has some precedent in other viral illnesses.

A paper in the journal The Lancet last week showed that the virus can infect the inner cell layer of organs and of blood vessels, called the endothelium. This, in theory, could interfere with the clotting process.

According to Brosnahan, while thinners like Heparin are effective in some patients, they don't work for all patients because the clots are at times too small.

"There are too many microclots," she said. "We're not sure exactly where they are."

Autopsies have in fact shown some people's lungs filled with hundreds of microclots.

The arrival of a new mystery however helps solve a slightly older one.

Cecilia Mirant-Borde, an intensive care doctor at a military veterans hospital in Manhattan, told AFP that lungs filled with microclots helped explain why ventilators work poorly for patients with low blood oxygen.

Earlier in the pandemic doctors were treating these patients according to protocols developed for acute respiratory distress syndrome, sometimes known as "wet lung."

But in some cases, "it's not because the lungs are occupied with water" -- rather, it's that the microclotting is blocking circulation and blood is leaving the lungs with less oxygen than it should.

It has just been a little under five months since the virus emerged in Wuhan, China, and researchers are learning more about its impact every day.

"While we react surprised, we shouldn't be as surprised as we were. Viruses tend to do weird things," said Brosnahan.

While the dizzying array of complications may seem daunting, "it's possible there'll be one or a couple of unifying mechanisms that describe how this damage happens," she said.

"It's possible it's all the same thing, and that there'll be the same solution."

New Delhi, May 28: Twitter CEO Jack Dorsey today reinforced his stance on pointing out "incorrect or disputed information about elections globally", a day after US President Donald Trump threatened to shutter social media over Twitter's actions on his posts.

Mr Dorsey appealed to "leave our employees out of this" as the face-off with Mr Trump is likely to escalate.

"Fact check: there is someone ultimately accountable for our actions as a company, and that's me. Please leave our employees out of this. We'll continue to point out incorrect or disputed information about elections globally. And we will admit to and own any mistakes we make," Mr Dorsey tweeted.

"This does not make us an 'arbiter of truth.' Our intention is to connect the dots of conflicting statements and show the information in dispute so people can judge for themselves. More transparency from us is critical so folks can clearly see the why behind our actions," said the Twitter CEO.

Fact check: there is someone ultimately accountable for our actions as a company, and that's me. Please leave our employees out of this. We'll continue to point out incorrect or disputed information about elections globally. And we will admit to and own any mistakes we make.

— jack (@jack) May 28, 2020

"Per our Civic Integrity policy (https://help.twitter.com/en/rules-and-policies/election-integrity-policy), the tweets yesterday may mislead people into thinking they don't need to register to get a ballot (only registered voters receive ballots). We're updating the link on

@realDonaldTrump tweet to make this more clear," Mr Dorsey tweeted.

Twitter had tagged two of Mr Trump's tweets in which he claimed that more mail-in voting would lead to what he called a "rigged election" this November. There is no evidence that attempts are being made to rig the election, and under the tweets Twitter posted a link which read: "Get the facts about mail-in ballots."

Five states in the US already conduct elections primarily by mail-in vote: Utah, Colorado, Hawaii, Washington and Oregon.

For years, Twitter has been accused of ignoring the US President's violation of platform rules with his daily, often hourly barrages of personal insults and inaccurate information sent to more than 80 million followers, news agency AFP reported.

But Twitter's slap on the wrist was enough to drive Mr Trump into a tirade - on Twitter - in which "Republicans feel that Social Media Platforms totally silence conservatives voices. We will strongly regulate, or close them down, before we can ever allow this to happen," Mr Trump said.

He said that an increase in mail-in ballots - seen in some states as vital for allowing people to avoid crowds during the COVID-19 pandemic - will undermine the election.

"It would be a free for all on cheating, forgery and the theft of Ballots," wrote Mr Trump, whose re-election campaign has been knocked off track by the coronavirus crisis. His torrent of angry tweets earned a top-10 trending hashtag: #TrumpMeltdown.

Facebook chief Mark Zuckerberg also waded in to the row, telling Fox News that his social network - still the biggest in the world - has a different policy. "I just believe strongly that Facebook should not be the arbiter of truth of everything that people say online," Mr Zuckerberg said in a snippet of the interview posted online Wednesday by Fox.

"I think, in general, private companies, especially these platform companies, shouldn't be in the position of doing that," he said.

 he claimed that the political right in the US is being censored.

"Republicans feel that Social Media Platforms totally silence conservatives voices. We will strongly regulate, or close them down, before we can ever allow this to happen," Mr Trump said.

He said that an increase in mail-in ballots - seen in some states as vital for allowing people to avoid crowds during the COVID-19 pandemic - will undermine the election.

"It would be a free for all on cheating, forgery and the theft of Ballots," wrote Mr Trump, whose re-election campaign has been knocked off track by the coronavirus crisis. His torrent of angry tweets earned a top-10 trending hashtag: #TrumpMeltdown.

Facebook chief Mark Zuckerberg also waded in to the row, telling Fox News that his social network - still the biggest in the world - has a different policy. "I just believe strongly that Facebook should not be the arbiter of truth of everything that people say online," Mr Zuckerberg said in a snippet of the interview posted online Wednesday by Fox.

"I think, in general, private companies, especially these platform companies, shouldn't be in the position of doing that," he said.

Mar 13: Canadian Prime Minister Justin Trudeau and his wife announced they were self-isolating Thursday as she undergoes tests for the new coronavirus after returning from a speaking engagement with "mild flu-like symptoms."

Sophie Gregoire-Trudeau's symptoms have subsided since she recently got back from Britain, but as a precaution the prime minister "will spend the day in briefings, phone calls and virtual meetings from home," according to a statement.

Trudeau also cancelled a meeting Thursday and Friday with Canada's provincial and territorial leaders in Ottawa, but still planned to speak with them and world leaders by phone about measures being taken to curb the spread of the virus in Canada.

Gregoire-Trudeau's symptoms had included "a low fever late last night." She immediately sought medical advice and testing.

Trudeau has exhibited no symptoms, and was advised by doctors "to continue daily activities while self-monitoring."

"However, out of an abundance of caution, the prime minister is opting to self-isolate and work from home until receiving Sophie's results," said his office.

Since the novel coronavirus first emerged in late December 2019, 127,070 cases have been recorded in 115 countries and territories, killing 4,687 people, according to an AFP tally compiled at 1200 GMT on Thursday based on official sources.

Canada has so far reported more than 100 cases in six provinces, and one death.

Also Thursday, the Canada's Juno music awards cancelled its upcoming gala show, planned for Sunday evening in Saskatoon, Saskatchewan.

"We are devastated to cancel this national celebration of music, but at this time of global uncertainty, the health, safety and well-being of all Canadians must stand at the forefront of any decisions that impact our communities," organisers said in a statement.

And in Quebec province, Premier Francois Legault unveiled a series of measures to prevent the spread of the coronavirus, including placing all travellers returning from overseas under quarantine for two weeks.

Quebec also banned indoor gatherings of more than 250 people.