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COVID-19 can be spread by building ventilation, say Canadian researchers – Toronto Sun

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Tom Blackwell, Postmedia News

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’ 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,” said Prof. Brian Fleck, part of the project. “There are so many, many, many buildings … This affects 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.

“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.

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COVID-19 study linking hydroxychloroquine, death risk retracted from medical journal – Global News

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Three of the authors of an influential article that found hydroxychloroquine increased the risk of death in COVID-19 patients retracted the study on Thursday, citing concerns about the quality of the data behind it.

The anti-malarial drug has been controversial in part due to support from U.S. President Donald Trump, as well as implications of the study published in British medical journal the Lancet last month.

READ MORE: Medical journal questioning findings of hydroxychloroquine coronavirus study

The three authors said Surgisphere, the company that provided the data, would not transfer the full dataset for an independent review and that they “can no longer vouch for the veracity of the primary data sources.”

The fourth author of the study, Dr. Sapan Desai, the CEO of Surgisphere, declined to comment on the retraction.

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The observational study published in the Lancet on May 22 looked at 96,000 hospitalized COVID-19 patients, some treated with the decades-old malaria drug. It claimed that those treated with hydroxychloroquine or the related chloroquine had higher risk of death and heart rhythm problems than patients who were not given the medicines.






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WHO halts hydroxychloroquine clinical trials


WHO halts hydroxychloroquine clinical trials

Several clinical trials were put on hold after the study was published. The World Health Organization, which paused hydroxychloroquine trials after The Lancet study was released, said on Wednesday it was ready to resume trials.

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Many scientists voiced concern about the study. Nearly 150 doctors signed an open letter to the Lancet last week calling the article’s conclusions into question and asking to make public the peer review comments that preceded publication.


READ MORE:
Hydroxychloroquine doesn’t prevent COVID-19 in people exposed to the virus, study finds

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“I did not do enough to ensure that the data source was appropriate for this use,” the study’s lead author, Harvard Medical School Professor Mandeep Mehra, said in a statement. “For that, and for all the disruptions – both directly and indirectly – I am truly sorry.”

Surgisphere was not immediately available for comment.

The Lancet in a statement said, “there are many outstanding questions about Surgisphere and the data that were allegedly included in this study.”

© 2020 Reuters

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N.B. to welcome Canadians with immediate family, property in province – CBC.ca

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New Brunswick plans to open its borders to Canadians who have immediate family in the province or who own property, starting June 19, provided they self-isolate for 14 days, Premier Blaine Higgs announced Thursday.

Cabinet and the all-party COVD-19 committee have also deemed attending funerals in New Brunswick essential travel, he told reporters during a news conference in Fredericton.

The decision to loosen restrictions comes the same day New Brunswick had its first COVID-19-related death and a new confirmed case —  both linked to a long-term care facility in the Campbellton region, where there is an outbreak.

Daniel Ouellette, 84, who tested positive for COVID-19 at the Manoir de la Vallée in Atholville last week, died Thursday morning at the Campbellton Regional Hospital.

Four other elderly residents and four employees have also tested positive for the respiratory disease, including the latest case, a health-care worker in their 20s.

They are among a cluster of 15 active cases now in the Campbellton region, also known as Zone 5.

Daniel Ouellette, 84, was one of 15 people who tested positive for COVID-19 in the Campbellton region. He died Thursday morning. (Submitted by Michel Ouellette)

Higgs said he, like all New Brunswickers, received the news “with a heavy heart” and offered his condolences.

But the rest of the province will move forward with the next phase of the yellow level of the COVID-19 recovery plan tomorrow, as scheduled, he said. The Campbellton region will remain under the stricter orange phase.

“We are grieving today, but we are also moving forward today,” said Higgs, describing it as a “combination of sadness and hope.”

On Tuesday, Tide Head Mayor Randy Hunter said there were more vehicles with Quebec licence plates in the area than there should be considering COVID-19 restrictions. (Google Maps)

Officials have linked the outbreak that started May 21 to a medical professional who travelled to Quebec for personal reasons and returned to work without self-isolating for the required 14 days.

Dr. Jean Robert Ngola told Radio-Canada’s program La Matinale on Tuesday he’s not sure whether he picked up the coronavirus during the trip to Quebec or from a patient he saw in his office on May 19 who later tested positive.

Ngola, who has been suspended and is under investigation by the RCMP, said he made an overnight return trip to Quebec to pick up his four-year-old daughter because her mother had to travel to Africa for her own father’s funeral.

He drove straight there and back with no stops and had no contact with anyone, he said, and none of his family members had any COVID-19 symptoms at the time.

He did not self-isolate upon returning, he said. He went to work at the Campbellton Regional Hospital the next day.

“Maybe it was an error in judgment,” said Ngola, pointing out that workers, including nurses who live in Quebec, cross the border each day with no isolation required.

Minister defends northern border crossing

The province’s public safety minister is defending a border crossing that residents of a small village near Campbellton fear is letting in too many people from out of the province.

On Tuesday, Tide Head Mayor Randy Hunter said there were more vehicles with Quebec licence plates in the area than there should be considering COVID-19 restrictions and that the province is giving the wrong impression about how much traffic there is at the crossing.

“The premier’s reporting and the news is reporting perhaps 60 to 70 cars a day, well that is not factual,” said Hunter.

Public Safety Minister Carl Urquhart said he’s convinced there isn’t a security issue at the border. (CBC)

“I know people that work for public safety there and the average [number of cars] on that bridge is about 200 a day.”

The checkpoint is located on the New Brunswick side of the border, a short distance from the bridge to Matapédia, Que.

But Public Safety Minister Carl Urquhart said there was a bit missing in that interpretation.

There are about 200 vehicles making that crossing every day, but only 65 of them would be private vehicles.

“Approximately 65 [private vehicles] the other day and then 130 commercial. So you’re looking at approximately 200 all together,” said Urquhart.

Urquhart said public safety officers are the ones that determine whether someone can come into the province or not, but that commercial vehicles are checked to make sure they’re actually making deliveries.

Urquhart said he’s convinced there isn’t a security issue at the border, and while he would love to send more public safety officers up there, they’re needed elsewhere.

“If I had a lot more people I could put them all over the province,” said Urquhart.

“You have to work with all you have.”

What to do if you have symptoms

People concerned they might have COVID-19 can take a self-assessment on the government website at gnb.ca. 

Public Health says symptoms shown by people with COVID-19 have included: a fever above 38 C, a new cough or worsening chronic cough, sore throat, runny nose, headache, new onset of fatigue, new onset of muscle pain, diarrhea, loss of sense of taste or smell, and difficulty breathing. In children, symptoms have also included purple markings on the fingers and toes.

People with two of those symptoms are asked to:

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Study authors retract influential Lancet hydroxychloroquine article – National Post

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NEW YORK — Three of the authors of an influential article that found hydroxychloroquine increased the risk of death in COVID-19 patients retracted the study on concerns about the quality of the data in the study.

They said that Surgisphere, the company that provided the data, would not transfer the full dataset for an independent review and they “can no longer vouch for the veracity of the primary data sources.”

The study was published in British medical journal the Lancet last month. (Reporting by Michael Erman Editing by Chris Reese)

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