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Scientists warn of overlooked danger from coronavirus-spreading airborne microdroplets – CTV News

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TORONTO —
Physical distancing and frequent handwashing are not enough to fully protect against airborne transmission of the novel coronavirus, hundreds of scientists say.

Virus-carrying microdroplets pose more of a danger than is currently being communicated, the scientists argue in a new medical commentary, and the result is that poor ventilation is easing the path of the pandemic.

The commentary has been accepted for publication in the journal Clinical Infectious Diseases. It is signed by 239 scientists from 32 countries and a wide variety of science and engineering disciplines, according to a statement from the Queensland University of Technology (QUT) in Australia.

“We are concerned that people may think they are fully protected by following the current recommendations, but in fact, additional airborne precautions are needed to further reduce the spread of the virus,” lead author and QUT air quality expert Lidia Morawska said in the statement.

MICRODROPLETS EXPLAINED

It is not controversial to say that the virus that causes COVID-19 can spread through exhaled airborne droplets. This is why physical distancing was one of the earliest individual measures urged to stop the spread of the virus, because putting space between people allows for particles to fall to the ground rather than latch on to another person.

It is also normal for viruses to be passed through droplets. Measles, for example, has an airborne transmission pathway that poses far more of a danger than has thus far been found with COVID-19.

“I can be in a room with measles, and leave, and somebody walks in hours later and they can get measles,” Dr. Sumon Chakrabati, an infectious diseases physician based in Missisauga, Ont., said Monday on CTV News Channel.

The World Health Organization says the droplets that carry SARS-CoV-2 can be spread through actions including coughing, sneezing and speaking, and recommends that everyone keep a one-metre distance from others. Many countries, including Canada, have gone farther, recommending a distance of two metres.

However, there are signs that the smallest microdroplets can travel beyond the two-metre limit. One American study found that they can move three metres in 12 seconds, and a fourth metre as they linger in the air for up to a minute. Morawska said that there is significant evidence that microdroplets can travel even farther – into the tens of metres – especially when indoors.

“Studies by the signatories and other scientists have demonstrated beyond any reasonable doubt that viruses are exhaled in microdroplets small enough to remain aloft in the air and pose a risk of exposure beyond [one to two metres] by an infected person,” she said.

“Hand-washing and social distancing are appropriate, but … insufficient to provide protection from virus-carrying respiratory microdroplets released into the air by infected people.”

‘IS THERE A DANGER THERE?’

Advice from public health experts in Canada and elsewhere has largely downplayed the risk of airborne transmission of the virus, even as evidence mounts that it is a real threat. In one study cited in the commentary as an example, droplets were found to be the most likely source of transmission among three dining parties at a restaurant in China, in a case where surveillance video footage showed no direct or indirect contact between the groups.

The debate over droplets has been playing out since the pandemic took hold. Dr. Colin Furness, a Toronto-based infection control epidemiologist, described it as “a pretty serious fight, intellectually,” but said the commentary is unlikely to lead to significant changes in virus protection thinking.

“The concern is ‘Are we ignoring those small droplets? Is there a danger there? Are our interventions maybe not enough?'” he said Monday on CTV News Channel.

“It could be that a smaller dose, those smaller droplets, actually matter for [COVID-19] because it’s so good at getting a toehold in your body once it gets in there.”

In Chakrabati’s view, the possibility of airborne transmission is overshadowed by the evidence that Canada and other countries have been able to slow the spread of the virus with the current precautions and restrictions.

“Are there situations where the two metres is a bit too little, for example a karaoke bar or a choir, where you’re singing and your voice is propelling? Perhaps,” he said.

“But I think for the most part, the recommendations that have been there since the beginning are the ones that are truly preventing the spread of this virus.”

REDUCING THE RISK

Morawska said that effective ventilation systems are the best way to reduce the spread of microdroplets. She said the most effective systems minimize the use of recirculated air by bringing in as much clean air from outdoors as possible, and that even opening doors and windows can make a major difference.

These ventilation techniques can be augmented with the use of air filtration and exhaust devices, as well as ultraviolet (UV) lights that kill germs. Another way to lessen the risk of microdroplet transmission is to avoid situations of overcrowding, especially on public transport and in public buildings, Morawka said.

Furness agreed with the suggestion to use UV lights in air filtration systems, saying that there could be a “renaissance” in this practice because the light can be effective against the virus in a way that physical filters cannot.

“I think we will probably see a resurgence in the use of UV light within air circulation systems, because UV light will kill viruses and it doesn’t really matter how small they are,” he said.

Face masks do not play a role in protecting against microdroplets, Furness said, because the droplets are so small that they can fit through the holes in most masks.

“If we were really concerned about aerosol, if we were really concerned about airborne, we would also be finding that wearing face coverings typically didn’t have that much of an effect – but the evidence says that they do,” he said.

“It’s not that we dramatically need to change what we are doing, it’s a question of trying to better understand our adversary and better understand what some of those risks may be.”

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Health Canada approves updated Moderna COVID-19 vaccine

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TORONTO – Health Canada has authorized Moderna’s updated COVID-19 vaccine that protects against currently circulating variants of the virus.

The mRNA vaccine, called Spikevax, has been reformulated to target the KP.2 subvariant of Omicron.

It will replace the previous version of the vaccine that was released a year ago, which targeted the XBB.1.5 subvariant of Omicron.

Health Canada recently asked provinces and territories to get rid of their older COVID-19 vaccines to ensure the most current vaccine will be used during this fall’s respiratory virus season.

Health Canada is also reviewing two other updated COVID-19 vaccines but has not yet authorized them.

They are Pfizer’s Comirnaty, which is also an mRNA vaccine, as well as Novavax’s protein-based vaccine.

This report by The Canadian Press was first published Sept. 17, 2024.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

The Canadian Press. All rights reserved.

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These people say they got listeria after drinking recalled plant-based milks

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TORONTO – Sanniah Jabeen holds a sonogram of the unborn baby she lost after contracting listeria last December. Beneath, it says “love at first sight.”

Jabeen says she believes she and her baby were poisoned by a listeria outbreak linked to some plant-based milks and wants answers. An investigation continues into the recall declared July 8 of several Silk and Great Value plant-based beverages.

“I don’t even have the words. I’m still processing that,” Jabeen says of her loss. She was 18 weeks pregnant when she went into preterm labour.

The first infection linked to the recall was traced back to August 2023. One year later on Aug. 12, 2024, the Public Health Agency of Canada said three people had died and 20 were infected.

The number of cases is likely much higher, says Lawrence Goodridge, Canada Research Chair in foodborne pathogen dynamics at the University of Guelph: “For every person known, generally speaking, there’s typically 20 to 25 or maybe 30 people that are unknown.”

The case count has remained unchanged over the last month, but the Public Health Agency of Canada says it won’t declare the outbreak over until early October because of listeria’s 70-day incubation period and the reporting delays that accompany it.

Danone Canada’s head of communications said in an email Wednesday that the company is still investigating the “root cause” of the outbreak, which has been linked to a production line at a Pickering, Ont., packaging facility.

Pregnant people, adults over 60, and those with weakened immune systems are most at risk of becoming sick with severe listeriosis. If the infection spreads to an unborn baby, Health Canada says it can cause miscarriage, stillbirth, premature birth or life-threatening illness in a newborn.

The Canadian Press spoke to 10 people, from the parents of a toddler to an 89-year-old senior, who say they became sick with listeria after drinking from cartons of plant-based milk stamped with the recalled product code. Here’s a look at some of their experiences.

Sanniah Jabeen, 32, Toronto

Jabeen says she regularly drank Silk oat and almond milk in smoothies while pregnant, and began vomiting seven times a day and shivering at night in December 2023. She had “the worst headache of (her) life” when she went to the emergency room on Dec. 15.

“I just wasn’t functioning like a normal human being,” Jabeen says.

Told she was dehydrated, Jabeen was given fluids and a blood test and sent home. Four days later, she returned to hospital.

“They told me that since you’re 18 weeks, there’s nothing you can do to save your baby,” says Jabeen, who moved to Toronto from Pakistan five years ago.

Jabeen later learned she had listeriosis and an autopsy revealed her baby was infected, too.

“It broke my heart to read that report because I was just imagining my baby drinking poisoned amniotic fluid inside of me. The womb is a place where your baby is supposed to be the safest,” Jabeen said.

Jabeen’s case is likely not included in PHAC’s count. Jabeen says she was called by Health Canada and asked what dairy and fresh produce she ate – foods more commonly associated with listeria – but not asked about plant-based beverages.

She’s pregnant again, and is due in several months. At first, she was scared to eat, not knowing what caused the infection during her last pregnancy.

“Ever since I learned about the almond, oat milk situation, I’ve been feeling a bit better knowing that it wasn’t something that I did. It was something else that caused it. It wasn’t my fault,” Jabeen said.

She’s since joined a proposed class action lawsuit launched by LPC Avocates against the manufacturers and sellers of Silk and Great Value plant-based beverages. The lawsuit has not yet been certified by a judge.

Natalie Grant and her seven year-old daughter, Bowmanville, Ont.

Natalie Grant says she was in a hospital waiting room when she saw a television news report about the recall. She wondered if the dark chocolate almond milk her daughter drank daily was contaminated.

She had brought the girl to hospital because she was vomiting every half hour, constantly on the toilet with diarrhea, and had severe pain in her abdomen.

“I’m definitely thinking that this is a pretty solid chance that she’s got listeria at this point because I knew she had all the symptoms,” Grant says of seeing the news report.

Once her daughter could hold fluids, they went home and Grant cross-checked the recalled product code – 7825 – with the one on her carton. They matched.

“I called the emerg and I said I’m pretty confident she’s been exposed,” Grant said. She was told to return to the hospital if her daughter’s symptoms worsened. An hour and a half later, her fever spiked, the vomiting returned, her face flushed and her energy plummeted.

Grant says they were sent to a hospital in Ajax, Ont. and stayed two weeks while her daughter received antibiotics four times a day until she was discharged July 23.

“Knowing that my little one was just so affected and how it affected us as a family alone, there’s a bitterness left behind,” Grant said. She’s also joined the proposed class action.

Thelma Feldman, 89, Toronto

Thelma Feldman says she regularly taught yoga to friends in her condo building before getting sickened by listeria on July 2. Now, she has a walker and her body aches. She has headaches and digestive problems.

“I’m kind of depressed,” she says.

“It’s caused me a lot of physical and emotional pain.”

Much of the early days of her illness are a blur. She knows she boarded an ambulance with profuse diarrhea on July 2 and spent five days at North York General Hospital. Afterwards, she remembers Health Canada officials entering her apartment and removing Silk almond milk from her fridge, and volunteers from a community organization giving her sponge baths.

“At my age, 89, I’m not a kid anymore and healing takes longer,” Feldman says.

“I don’t even feel like being with people. I just sit at home.”

Jasmine Jiles and three-year-old Max, Kahnawake Mohawk Territory, Que.

Jasmine Jiles says her three-year-old son Max came down with flu-like symptoms and cradled his ears in what she interpreted as a sign of pain, like the one pounding in her own head, around early July.

When Jiles heard about the recall soon after, she called Danone Canada, the plant-based milk manufacturer, to find out if their Silk coconut milk was in the contaminated batch. It was, she says.

“My son is very small, he’s very young, so I asked what we do in terms of overall monitoring and she said someone from the company would get in touch within 24 to 48 hours,” Jiles says from a First Nations reserve near Montreal.

“I never got a call back. I never got an email”

At home, her son’s fever broke after three days, but gas pains stuck with him, she says. It took a couple weeks for him to get back to normal.

“In hindsight, I should have taken him (to the hospital) but we just tried to see if we could nurse him at home because wait times are pretty extreme,” Jiles says, “and I don’t have child care at the moment.”

Joseph Desmond, 50, Sydney, N.S.

Joseph Desmond says he suffered a seizure and fell off his sofa on July 9. He went to the emergency room, where they ran an electroencephalogram (EEG) test, and then returned home. Within hours, he had a second seizure and went back to hospital.

His third seizure happened the next morning while walking to the nurse’s station.

In severe cases of listeriosis, bacteria can spread to the central nervous system and cause seizures, according to Health Canada.

“The last two months have really been a nightmare,” says Desmond, who has joined the proposed lawsuit.

When he returned home from the hospital, his daughter took a carton of Silk dark chocolate almond milk out of the fridge and asked if he had heard about the recall. By that point, Desmond says he was on his second two-litre carton after finishing the first in June.

“It was pretty scary. Terrifying. I honestly thought I was going to die.”

Cheryl McCombe, 63, Haliburton, Ont.

The morning after suffering a second episode of vomiting, feverish sweats and diarrhea in the middle of the night in early July, Cheryl McCombe scrolled through the news on her phone and came across the recall.

A few years earlier, McCombe says she started drinking plant-based milks because it seemed like a healthier choice to splash in her morning coffee. On June 30, she bought two cartons of Silk cashew almond milk.

“It was on the (recall) list. I thought, ‘Oh my God, I got listeria,’” McCombe says. She called her doctor’s office and visited an urgent care clinic hoping to get tested and confirm her suspicion, but she says, “I was basically shut down at the door.”

Public Health Ontario does not recommend listeria testing for infected individuals with mild symptoms unless they are at risk of developing severe illness, such as people who are immunocompromised, elderly, pregnant or newborn.

“No wonder they couldn’t connect the dots,” she adds, referencing that it took close to a year for public health officials to find the source of the outbreak.

“I am a woman in my 60s and sometimes these signs are of, you know, when you’re vomiting and things like that, it can be a sign in women of a bigger issue,” McCombe says. She was seeking confirmation that wasn’t the case.

Disappointed, with her stomach still feeling off, she says she decided to boost her gut health with probiotics. After a couple weeks she started to feel like herself.

But since then, McCombe says, “I’m back on Kawartha Dairy cream in my coffee.”

This report by The Canadian Press was first published Sept. 16, 2024.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

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B.C. mayors seek ‘immediate action’ from federal government on mental health crisis

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VANCOUVER – Mayors and other leaders from several British Columbia communities say the provincial and federal governments need to take “immediate action” to tackle mental health and public safety issues that have reached crisis levels.

Vancouver Mayor Ken Sim says it’s become “abundantly clear” that mental health and addiction issues and public safety have caused crises that are “gripping” Vancouver, and he and other politicians, First Nations leaders and law enforcement officials are pleading for federal and provincial help.

In a letter to Prime Minister Justin Trudeau and Premier David Eby, mayors say there are “three critical fronts” that require action including “mandatory care” for people with severe mental health and addiction issues.

The letter says senior governments also need to bring in “meaningful bail reform” for repeat offenders, and the federal government must improve policing at Metro Vancouver ports to stop illicit drugs from coming in and stolen vehicles from being exported.

Sim says the “current system” has failed British Columbians, and the number of people dealing with severe mental health and addiction issues due to lack of proper care has “reached a critical point.”

Vancouver Police Chief Adam Palmer says repeat violent offenders are too often released on bail due to a “revolving door of justice,” and a new approach is needed to deal with mentally ill people who “pose a serious and immediate danger to themselves and others.”

This report by The Canadian Press was first published Sept. 16, 2024

The Canadian Press. All rights reserved.

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