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Could new virus variants derail COVID-19 vaccination efforts? Scientists hope not – CBC.ca

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After the virus behind COVID-19 spent 2020 wreaking havoc around the globe, this year started with a bit more hope — vaccination efforts were ramping up, after all — and a tinge of fear.

Multiple new coronavirus variants have been discovered across several continents, from Europe to Africa to South America. Confirmed cases keep popping up in dozens of countries, Canada included.

Scientists are now racing to understand these sets of mutations, all while concerns are growing over their ability to infect people more easily or, in some cases, potentially evade the army of antibodies we create after being infected or vaccinated.

And since widespread transmission means this virus has ample opportunities to mutate again and again and again, these variants won’t be the last. They’re just the ones we know about.

“The more opportunity we give to the virus to replicate, to make more viruses, the more opportunity there is to see that variant of concern — one that won’t be mitigated by our vaccines that we’ve developed,” warned Alyson Kelvin, a virologist at Dalhousie University and the IWK Health Centre in Halifax.

After months of work to develop safe, effective vaccines against SARS-CoV-2, the scientific community now faces a race against time to ward off that scenario.

There’s also a looming question: What happens if we don’t?

Variants could ‘very rapidly’ become prevalent

Kelvin, one of the many Canadian researchers involved in vaccine development, said preliminary data shows that the sets of mutations identified so far don’t yet seem to be an issue for current coronavirus vaccines.

That’s the good news. It’s the “yet” she finds troubling.

“We have to stay on top of this problem,” Kelvin said.

Alyson Kelvin, a virologist at Dalhousie University and the IWK Health Centre in Halifax, says preliminary data shows that the sets of mutations identified so far don’t yet seem to be an issue for current coronavirus vaccines. (Liam Richards/The Canadian Press)

But while new variants might throw a wrench in efforts to suppress transmission by popping up like a game of global whack-a-mole, those ongoing mutations were actually expected, not surprising.

That’s because each virus has a singular goal of replicating itself. With tens of millions of people helping move the coronavirus back and forth between hosts, that means countless replications. Some of those contain random, insignificant mistakes. And when the mistakes prove beneficial to the virus, helping it produce more copies, those errors can become a new normal of sorts — a variant.

It’s just evolution at work, said Angela Rasmussen, a virologist at Georgetown University’s Center for Global Health Science and Security in Washington, D.C., and incoming research scientist at the Vaccine and Infectious Disease Organization at the University of Saskatchewan in Saskatoon.

“What concerns me the most is that the epidemiological data that goes along with some of these variants suggests they could very rapidly become very prevalent — effectively out-competing the other variants in a given area — in a short period of time,” she said.

WATCH | How countries can control emerging coronavirus variants:

Alongside the use of vaccines, virologist and researcher Angela Rasmussen says countries can strive to control emerging coronavirus variants by beefing up surveillance efforts and encouraging the usual public health measures, from mask-wearing to avoiding gatherings. 1:13

Could new variants decrease immune response?

Researchers speculate that may be what happened with B117. The variant was first discovered in the U.K. late last year and is now the country’s dominant strain of the coronavirus — with various officials suggesting it’s at least 50 per cent more transmissible. (Cases have been confirmed in several provinces in Canada as well, and testing is ongoing.)

In the short term, more transmission means more infections, hospitalizations and deaths, Rasmussen said, which offers an incentive for countries to slow case growth. Doing so would both save lives and cut off channels for the virus to spread and mutate.

“It’s also possible that variants may arise that decrease the effectiveness of our immune response to the virus,” said Matthew Miller, a member of the Institute for Infectious Disease Research at McMaster University and the McMaster Immunology Research Centre in Hamilton.

“But also, of course — and perhaps more worryingly — the immune responses elicited by the currently approved vaccines.”

WATCH | A new coronavirus variant spreads through Brazil:

Three COVID-19 variants are now worrying health officials. The ones first identified in Britain and South Africa are already here. The third is spreading fast in Brazil and beyond. It may be better at dodging the immune response, and even reinfecting survivors. 3:36

For scientists in Brazil, there’s already legitimate cause for alarm.

“We have detected a new variant circulating in December in Manaus, Amazonas state, north Brazil, where very high attack rates have been estimated previously,” read the preliminary findings posted online by a research team led by Imperial College London virologist Nuno Faria.

The new lineage, dubbed P1, contains a “unique constellation” of mutations in the crucial spike protein, which helps the virus penetrate human cells, the report continues. The variant was detected in 42 per cent of samples collected during a stretch in December, but not in samples collected in the months before.

Those new cases also appeared even though an estimated three-quarters of people living in Manaus, the largest city in the Amazon region, had already been infected.

Faria’s report stressed that could mean an increase in transmissibility — the same issue with B117 — or even an ability to reinfect people.

Vaccines ‘modifiable’ in face of new mutations

According to Rasmussen, antibodies seem to have a reduced capacity to neutralize this kind of virus variant based on the spike protein mutations. Echoing Kelvin and Miller’s concerns, she said that’s a key problem, “because if you acquire enough of those mutations, you may get to a point where you have a variant capable of evading vaccine-induced immunity completely.”

But again, it’s not all dire news. Just because antibodies are less effective doesn’t necessarily mean someone would have reduced immune protection, Rasmussen explained, since the body’s immune response is looking at the entire spike protein, not just certain areas that might have a set of mutations.

Miller also noted that while the spike protein tends to be most prone to changing in the face of immunological pressure, there are other vaccine candidates in development that are designed to elicit broader immune responses against a greater array of viral targets to stay one step ahead.

WATCH | Scientists still researching whether vaccine prevents COVID-19 transmission:

As COVID-19 vaccines are administered around the world, scientists continue conducting research to determine how effective the shots are at preventing transmission of the virus. 4:44

“Even in the worst-case scenario, that we see some of these variants spreading and we get a partial response, it’s probably going to mean that the health-care complications, the deaths, are still going to be greatly controlled by a mass vaccine campaign,” said Dr. Zain Chagla, an infectious disease specialist at McMaster University.

And, thankfully, research teams can also pivot, redeveloping existing coronavirus vaccines to target any variants that may prove capable of evading the ones already rolling out globally.

The novel mRNA vaccines, including the Pfizer-BioNTech and Moderna options currently approved in Canada, are among those that can be more easily tweaked. Those vaccines provide instructions — messenger RNA — to cells, allowing them to make their own spike protein, which someone’s immune system can recognize and fight off in the future.

“That is their genius, that they’re completely and rapidly modifiable,” Chagla said. “The packaging is there, the delivery method is there, all you need to do is change the mRNA sequence.”

The sooner people get vaccinated, ‘the better’

But while the flexibility of vaccination development is reassuring for the long term, it doesn’t tackle the problem at hand: COVID-19 still has its grip on much of the world, the death toll keeps climbing and vaccination efforts remain a race against time as emerging variants keep throwing a wrench in efforts to curb transmission.

“The sooner that we can get a vaccine into people, the better,” Kelvin said.

To save lives and keep health-care systems from collapsing while vaccination programs scale up, she stressed that Canadians also need to ramp up the basic public health precautions that should now be routine.

Physical distancing, mask-wearing, hand-washing, staying away from crowds and enclosed spaces — it all matters, perhaps now more than ever, to slow transmission and give the virus fewer opportunities to spread and evolve.

That buys time for Canada to hit its tenuous goal for 2021: getting everyone vaccinated, without any variants getting in the way.

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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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