US confirms 1,069,534 coronavirus cases, death toll at 63,001

Apr 26: The Chinese city of Wuhan, where the global coronavirus pandemic began, now has no remaining cases in its hospitals, a health official told reporters on Sunday.

"The latest news is that by April 26, the number of new coronavirus patients in Wuhan was at zero, thanks to the joint efforts of Wuhan and medical staff from around the country," National Health Commission spokesman Mi Feng said at a briefing.

The city had reported 46,452 cases, 56% of the national total. It saw 3,869 fatalities, or 84% of China's total.

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."

Beijing, Jan 21: The Chinese official investigating a pneumonia outbreak stemming from a new coronavirus said the disease can spread from person to person but can be halted with increased vigilance, as authorities on Tuesday confirmed a fourth death.

Zhong Nanshan said there was no danger of a repeat of the Severe Acute Respiratory Syndrome (SARS) epidemic that killed nearly 800 people globally during a 2002-2003 outbreak, which started in China, as long as precautions were taken.

"It took only two weeks to identify the novel coronavirus," state news agency Xinhua quoted Zhong as saying late on Monday.

The outbreak was still in its early stages and China had good surveillance and quarantine systems to help control it, he added.

The outbreak has spread from the central city of Wuhan to cities including Beijing and Shanghai, with more than 200 cases reported so far. Four cases have been reported outside China - in South Korea, Thailand and Japan.

Australia on Tuesday said it would screen passengers on flights from Wuhan amid rising concerns that the virus will spread globally as Chinese travellers take flights abroad for the Lunar New Year holiday starting this week.

Authorities around the globe, including in the United States and many Asian countries, have stepped up screening of travellers from Wuhan.

Chinese authorities confirmed a total of 217 cases of the virus in China as of 6 p.m. (1000 GMT) on Monday, state television reported, 198 of which were in Wuhan.

A fourth person died on Jan. 19, the Wuhan Municipal Health Commission said. The 89-year-old man, who had underlying health diseases including coronary heart disease, developed symptoms on Jan. 13 and was admitted to hospital five days later, it added.

Zhong, who is renowned in China for his work fighting SARS in 2003, confirmed that the virus can pass from person-to-person.

Fifteen medical workers in Wuhan had been diagnosed with pneumonia, with one other suspected case, the Wuhan Municipal Health Commission said. Of the infected staff, one was in critical condition.

In Shanghai, officials on Tuesday confirmed a second case involving a 35-year-man who had visited Wuhan in early January, and said they were monitoring four other suspected cases.

The virus causes a type of pneumonia and belongs to the same family of coronaviruses as SARS. Symptoms include fever and difficulty in breathing, which are similar to many other respiratory diseases and pose complications for screening efforts.

The World Health Organisation (WHO) said on Monday an animal source appeared most likely to be the primary origin of the outbreak and that some "limited human-to-human transmission" occurred between close contacts.

The Geneva-based U.N. agency convened an emergency committee for Wednesday to assess whether the outbreak constitutes an international health emergency and what measures should be taken to manage it.

So far, the WHO has not recommended trade or travel restrictions, but a panel of independent experts could do so or make other recommendations to limit spread.