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COVID-19 can be spread by building ventilation, say Canadian researchers working on an HVAC fix – National Post

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The outbreak of COVID-19 at a restaurant in the southern Chinese city of Guangzhou was a puzzle.

The suspected index patient was a visitor from the coronavirus’s epicentre in Wuhan. But the eight other customers who later tested positive were not sitting close enough for droplet transmission, and most of the patrons and staff avoided infection altogether.

A team of local scientists eventually came to an eye-opening conclusion about the episode: tiny particles of virus had hitched a ride on currents created by the eatery’s air-conditioning.

That runs counter to the prevailing view that the novel coronavirus is transmitted only by heavier “droplets.” But for a group of civil engineers at the University of Alberta, the finding was no surprise. In their world, they say, it’s well known that building ventilation systems are efficient disseminators of viruses and other pathogens, and they believe the COVID-19 bug is no exception.

Aided by a $440,000 federal-government grant, they’re now working on ways that buildings could change their HVAC set-ups to curb the risk of infection, what the researchers call a “non-pharmaceutical” intervention against the disease.

We want to save lives, let’s cut right to the chase

“We want to save lives, let’s cut right to the chase,” said Prof. Brian Fleck, part of the project. “There are so many, many, many buildings … This effects absolutely everybody. Billions of people. If we are able to cut down the transmission rate by a per cent, that’s a lot of people.”

The engineers’ belief in the importance of building ventilation as a transmitter of the COVID-19 virus is not universally held.

The World Health Organization and other public-health bodies, citing the science to date, say the pathogen is spread almost entirely by droplets, heavier particles emitted mostly when infected people cough or sneeze, and which fall down within a short distance. Hence the two-metre rule for social distancing, and the emphasis on washing hands after touching surfaces where virus may have alighted.

“The HVAC systems in most non-medical buildings play only a small role in infectious disease transmission, including COVID-19,” argued the American Society of Heating, Refrigerating, and Air-Conditioning Engineers last month.

It’s just smaller and lighter aerosol particles that can spread through a ventilation system and “the truth is that we still don’t really know if the (COVID-19) virus can be spread by aerosols,” said Matthew Miller, a virus expert at McMaster University in Hamilton.

But Chinese and Australian air-quality experts, citing in part the experience with SARS, another coronavirus, argued in a paper earlier this month that as droplets from an infected person start to evaporate, the resulting smaller particles can indeed become airborne.

They point to evidence that passengers confined to their cabins on cruise ships like the Diamond Princess may have been infected through the vessels’ air ducts.

“It is highly likely that the SARS-CoV-2 virus also spreads by air,” they conclude, urging “all possible” action in response, including modifications to ventilation systems. “We predict that … failure to immediately recognize and acknowledge the importance of airborne transmission and to take adequate actions against it will result in additional cases.”

Then there was the Guangzhou restaurant case, detailed in a U.S. Centers for Disease Control online journal recently. Researchers concluded flow from an air conditioner moved over three tables, carrying virus from the infected patron at the middle one to the far table, then back to the diners closest to the air conditioner.

Even if it turned out SARS-CoV-2 does not spread that way, influenza viruses can, and the University of Alberta research would be valuable for that reason alone, said Miller.

Heating, ventilation and air conditioning (HVAC) engineers have long known that tiny particles of pathogen travel in the air that is circulated, heated and cooled in modern buildings, said Fleck. He pointed to Legionnaires disease, a bacterial pneumonia first traced to a hotel’s air-conditioning system.

The particle can stay airborne long enough to go all the way through the system and then pop out in somebody else’s office

“This has been on people’s radar for quite a while,” he said. “Somebody on a different floor sneezes …The particle can stay airborne long enough to go all the way through the system and then pop out in somebody else’s office.”

There are various ways that the risk can be lessened, including use of filters that catch a greater number of those particles, and drawing more fresh air into a system. It also is likely that higher levels of humidity – a factor that only some Canadian buildings can adjust – will help kill off the virus, said Fleck.

But each of those changes carries a cost. Adding more fresh air can require additional heat or air conditioning. Heavier filters means more energy is needed to push the air through them. And more humidity can lead to mould, he noted.

“This will make for difficult decision making.”

Funded by the Canadian Institute for Health Research, the University of Alberta project is led by engineering professor Lexuan Zhong and also involves pediatrics professor Lisa Hartling. It consists of three phases: systematically reviewing literature on air circulation and viruses, determining what strategies would be effective and then carrying out a detailed audit of all the buildings on the Edmonton campus to create a real-world model of what should be done.

The team hopes to have solid results by the summer of 2021, said Fleck.

(Modified 12:40 April 26 to add comments by Matthew Miller.)

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Mother mystified by Winnipeg toddler's 'terrifying' condition after coming down with COVID-19 – Yahoo News Canada

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Mother mystified by Winnipeg toddler’s ‘terrifying’ condition after coming down with COVID-19

Doctors are investigating the case of a Winnipeg toddler with symptoms suggesting a rare, inflammatory illness potentially linked to COVID-19, the girl’s mother says.

The 21-month-old child is fighting to recover, even after she no longer tested positive for COVID-19.

The mother says health-care providers treating her daughter are concerned the girl may have developed Kawasaki disease, which is also known as multi-system inflammatory syndrome (MIS-C) in children.

Inflammatory syndromes can result from the body’s reaction to new viruses — not just the new coronavirus. But doctors in Canada, and scientists around the world, are investigating for a link to COVID-19.

Public health officials say no cases of the conditions connected with COVID-19 have been confirmed in Manitoba so far.

“Honestly, it’s just terrifying … Doctors don’t have the answers,” said the girl’s mother, who CBC is not naming due to concern about stigma.

The toddler’s parents didn’t know what to make of the her symptoms. She had a red, puffy rash, vomiting and diarrhea, a tender abdomen and a recurring fever that spiked to 38.9 C (102 F).

“She refused to eat, barely had anything to drink,” said her mother.

Pediatricians they contacted were cautious about sending the child to a hospital, and told the mother to try Tylenol, thinking the girl had a flu.

On April 28, two days after the girl’s symptoms arose, the family learned the husband has been exposed to a co-worker who later tested positive for COVID-19.

They went for testing immediately, and blood work confirmed the toddler had COVID-19, the mother said.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="WATCH | Toronto doctor answers questions about inflammatory syndrome following COVID-19” data-reactid=”34″>WATCH | Toronto doctor answers questions about inflammatory syndrome following COVID-19

At that point, Manitoba had fewer than 25 active cases of the disease and was announcing plans for reopening.

“It was absolutely devastating,” the mother said. “How could it possibly be COVID … with the cases being so low?”

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="‘More unknowns than knowns’” data-reactid=”37″>‘More unknowns than knowns’

A provincial spokesperson said since Kawasaki disease isn’t required to be reported in Manitoba, officials can’t confirm investigations into the illness in Manitoba.

The spokesperson said Manitoba pediatric infectious disease experts are in constant communication with specialists in Ontario and Quebec.

Hospitals in Ontario, Quebec, B.C. and Alberta are examining possible cases of MIS-C. Experts say the illness is difficult to diagnose and cases remain ill defined.

“There are way more unknowns than knowns,” said Rae Yeung, a professor of pediatrics, immunology and medical sciences at the University of Toronto, and staff pediatrician and rheumatologist at the Hospital for Sick Children.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content=""Right now, the big challenge is that there is not one diagnostic test&nbsp;… that can actually tell us whether a child has MIS-C or Kawasaki disease, [which are] all one hyper-inflammatory syndrome," said Yeung.” data-reactid=”42″>”Right now, the big challenge is that there is not one diagnostic test … that can actually tell us whether a child has MIS-C or Kawasaki disease, [which are] all one hyper-inflammatory syndrome,” said Yeung.

“As we’re learning, the one common denominator is that they have massive immune activation. But many things can cause massive immune activation.”

When she’s not sick, the child in Winnipeg is “very chatty. She’s energetic, running around,” said her mother. 

COVID-19 sucked that energy away as the toddler mostly slept.

Eventually, “she was only awake approximately three hours in a 24-hour period,” her mother said.

After she tested positive, doctors admitted the toddler to the hospital for treatment and testing to rule out anything else that may have been making her sicker.

Initially, doctors hoped her body could fight off the disease on its own, her mother said. But the family has been in and out of the hospital for weeks as her condition remained serious.

Last week, the toddler’s health took a turn for the worse. But on May 28, tests showed she’s now negative for COVID-19 and is fighting a new medical battle.

Doctors then raised the possibility of MIS-C or Kawasaki, the mother said, and will now begin further tests to help understand exactly what is making her daughter so ill.

“You just kind of feel helpless because you can’t make [your children] feel better,” she said.

“You don’t want to see them sick, especially with something so serious as a pandemic. You just wish you could take their pain away.”

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="The syndrome with many names” data-reactid=”57″>The syndrome with many names

Yeung calls MIS-C “the syndrome with many different names,” because depending on where you are in the world, it might be called different things.

“I think this is part of the reason why it’s led to some confusion and a lot of anxiety, in fact, among not only families, but also caregivers and health-care professionals,” she said.

Much of what’s known about the disease remains hypothetical, she said, and research is needed to understand more. At its core, the syndrome can be characterized by inflammation, especially in blood vessels, caused by a hyperactivation of the immune system.

“What we’re seeing in all of these syndromes is hyper inflammation —  just an overactive immune system that’s gone into overdrive, affecting multiple organs in the body,” she said.

The illnesses in that family are triggered by a “tickle” to the immune system, Yeung said, starting with anything from strep throat to the novel coronavirus. Canada documents roughly 100 to 150 cases of Kawasaki disease a year, she said.

But epidemiology in Europe, the U.S. and Canada has suggested a pattern, as cases of inflammatory syndromes in children emerge roughly four to six weeks following the peak coronavirus outbreak in each population.

Many, even most, of the children diagnosed with these illnesses don’t initially test positive when swabbed for COVID-19, Yeung said, but blood work often shows the children had the disease previously.

It’s still not clear exactly how many cases of the inflammatory illness there are in Canada, Yeung said. She said at Toronto’s Hospital for Sick Children, they’re seeing roughly three to four times the volume of these illnesses over normal years.

Yeung is helping lead research, in partnership with the Canadian Paediatric Society and the Public Health Agency of Canada, with doctors across the country to determine where cases are and help understand them better.

“I think sharing knowledge and alerting the public is a very important component of this,” Yeung said.

The mother of the Winnipeg toddler said she wanted to share her story to spread information and urge caution from parents.

“It’s rare, but it’s serious,” the mother said. “If you’re in doubt, take your child to the hospital.”

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Scenes of SpaceX launching NASA astronauts into orbit, moment by moment – CNET

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SpaceX’s Crew Dragon spacecraft, perched atop the company’s Falcon 9 rocket, takes off from launch pad 39A at the Kennedy Space Center in Cape Canaveral, Florida, carrying NASA astronauts Robert Behnken and Douglas Hurley to the International Space Station. The May 30 launch was the first US rocket launch with a crew since the Space Shuttle program ended in 2011 and SpaceX’s first crewed mission ever. The mission is called Demo-2 since its primary purpose is to test out SpaceX’s spacecraft.

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An Asteroid Bigger Than The Empire State Building Poses ‘No Danger’ On Saturday Night, Says NASA – Forbes

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A huge near-Earth asteroid will pass our planet tonight at a safe distance of 3.2 million miles, according to NASA.

After a spate of doom-laden headlines the space agency felt the need yesterday to update a previous post about near-Earth asteroids with the following note:

“Asteroid 2002 NN4 will safely pass by the Earth on June 6 at a distance of approximately 3.2 million miles (5.1 million kilometers), about 13 times further away from the Earth than the Moon is. There is no danger the asteroid will hit the Earth.”

Asteroid 2002 NN4’s closest approach to Earth will be at 11:20 p.m. EDT. on Saturday, June 6, 2020.

NASA also tweeted the same advice:

NASA Asteroid Watch then tweeted this image of the asteroid’s trajectory:

How big is Asteroid 2002 NN4?

Asteroid 2002 NN4 is huge. Measuring between 820 feet and 1,870 feet (250 meters to 570 meters) according to Space.com. New York City’s Empire State Building is 443.2 meters tall, including its antenna.

That’s over a dozen times bigger than the asteroid that exploded over Chelyabinsk, Russia, in 2013. That was the biggest meteor for over a century.

Would asteroid 2002 NN4 be dangerous if it hit Earth?

Yes—asteroid 2002 NN4 is city-killer size, but it’s not going to cause any harm to anyone.

Wishing you clear skies and wide eyes.

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