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Coronavirus vaccine: what we know so far – a comprehensive guide by academic experts – CanadianManufacturing.com

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Since the early days of the pandemic, attention has focused on producing a vaccine for COVID-19. With one, it’s hoped it will be able to suppress the virus without relying purely on economically challenging control measures. Without one, the world will probably have to live with COVID-19 as an endemic disease. It’s unlikely the coronavirus will naturally burn itself out.

With so much at stake, it’s not surprising that COVID-19 vaccines have become both a public and political obsession. The good news is that making one is possible: the virus has the right characteristics to be fended off with a vaccine, and the economic incentive exists to get one (or indeed several) developed.

But we need to be patient. Creating a new medicine requires a large amount of thought and scrutiny to make sure what’s produced is safe and effective. Researchers must be careful not to allow the pressure and allure of creating a vaccine quickly to undermine the integrity of their work. The upshot may be that we don’t have a highly effective vaccine against COVID-19 for some time.

Here, authors from across The Conversation outline what we know so far. Drawing upon their expertise, they explain how a COVID-19 vaccine will work, the progress a leading vaccine (developed by the University of Oxford with AstraZeneca) is making, and what challenges there will be to manufacturing and rolling a vaccine out when ready.

How will vaccines work for COVID-19?
How the spike protein is produced
The benefits of different designs
Why boosters may be needed
What determines how we respond to vaccines
Why vaccines provide strong immunity
How to use a vaccine when it’s available

How is the Oxford vaccine being developed, tested and approved?
The many steps of vaccine development
The results of phase 1 and phase 2 trials
How the phase 3 trial will work
Why testing was paused – and why we shouldn’t be alarmed
Why vaccine makers need to be more open
Why we need to know what’s in placebos

How will the vaccine be made and rolled out?
How to prepare enough vaccines for the whole world
How tobacco could play a role in producing a vaccine
Why vaccines need to be kept cold
Will rich countries buy up the supply when vaccines are available?
How to stop rich countries from depriving poorer ones
Who should get a vaccine first?

How do you counter resistance and scepticism?
Vaccine hesitancy is nothing new
Are anti-vaxxers that big a problem?
How the far right is exploiting the pandemic
How to build trust in vaccines


How will vaccines work for COVID-19?

Producing the spike protein

Although the way the body interacts with SARS-CoV-2 isn’t fully understood, there’s one particular part of the virus that’s thought to trigger an immune response – the spike protein, which sticks up on the virus’s surface. Therefore, the two leading COVID-19 vaccines both focus on getting the body to produce these key spike proteins, to train the immune system to recognise them and destroy any viral particles that exhibit them in the future.

The pros and cons of different designs

The leading vaccines both work by delivering a piece of the coronavirus’s genetic material into cells, which instructs the cell to make copies of the spike protein. As Suresh Mahalingam and Adam Taylor explain, one (Moderna’s) makes the delivery using a molecule called messenger RNA, the other (AstraZeneca’s) using a harmless adenovirus. These cutting-edge vaccine designs have their pros and cons, as do traditional methods.

Boosters may be needed

The strongest immune responses, says Sarah Pitt, come from vaccines that contain a live version of what they’re trying to protect against. Because there’s so much we don’t know about SARS-CoV-2, putting a live version of the virus into a vaccine can be risky. Safer methods – such as getting the body to make just the virus’s spike proteins, or delivering a dead version of the virus – will lead to a weaker response that fades over time. But boosters can top this up.

What governs how we respond to vaccines?

A vaccine’s design isn’t the only factor that determines how strong our immune response is. As Menno van Zelm and Paul Gill show, there are four other variables that make each person’s response to a vaccine unique: their age, their genes, lifestyle factors and what previous infections they have been exposed to. It may be that not everyone gets long-lasting immunity from a vaccine.

Why vaccines provide strong immunity

If well-designed, a vaccine can provide better immunity than natural infection, says Maitreyi Shivkumar. This is because vaccines can focus the immune system on targeting recognisable parts of the pathogen (for example the spike protein), can kickstart a stronger response using ingredients called adjuvants, and can be delivered to key parts of the body where an immune response is needed most. For COVID-19, this could be the nose.

How to use a vaccine when it’s available

Scientists think between 50% and 70% of people need to be resistant to the coronavirus to stop it spreading. Using a vaccine to rapidly make that many people immune might be difficult, says Adam Kleczkowski. Vaccines are rarely 100% effective, and hesitancy and potential side effects may make a quick, mass roll-out unrealistic. A better strategy might be to target people most at risk together with those likely to infect many others.


How is the Oxford vaccine being developed, tested and approved?

The many steps of vaccine development

Vaccine development is quicker now than it ever has been, explain Samantha Vanderslott, Andrew Pollard and Tonia Thomas. Researchers can use knowledge from previous vaccines, and in an outbreak more resources are made available. Nevertheless, it’s still a lengthy process, involving research on the virus, testing in animals and clinical trials in humans. Once approved, millions of doses then need to be produced.

Phase 1 and phase 2 trials are successful

After showing promise in animals, the University of Oxford’s vaccine moved onto human testing – known as clinical trials, which are split into three phases. Here, Rebecca Ashfield outlines the joint phase 1 and 2 trial that the vaccine passed through to check that it was safe and elicited an immune response, and explains how the vaccine actually uses a separate virus – a chimpanzee adenovirus – to deliver its content into cells.

How the phase 3 trial works

Earlier trial phases showed that the vaccine stimulated the immune system, as expected. But the million-dollar question is whether this actually protects against COVID-19. Finding out means giving the vaccine to thousands of people who might be exposed to the coronavirus and seeing whether they get sick. As Ashfield and Pedro Folegatti show, this requires running vaccination programmes in countries across the world.

Testing was paused – and that’s OK

In September, the phase 3 trial of the Oxford vaccine was paused after a patient fell ill with a possible adverse reaction. Understandably this caused dismay, but it shouldn’t have, says Simon Kolstoe. Pauses like this are common, as independent moderators are needed to assess exactly what has happened. Often illnesses in trials are unrelated to what’s being tested. But even if they are, that’s exactly what we want these tests to show.

But vaccine makers need to be more open

AstraZeneca didn’t publicly reveal what caused the pause but did share this information with investors. This, says Duncan Matthews, was an example of an attempt to apply old methods of operating to a new situation.

Why we need to know what’s in placebos

A key part of clinical trials are placebos – alternative or inactive treatments that are given to participants for comparison. But a key problem, Jeremy Howick explains, is that some vaccine trials don’t reveal what their placebos contain. Without knowing what benchmark is being used, it’s then difficult for outsiders to understand the relative effect (and side effects) the vaccine has.


How will the vaccine be made and rolled out?

Preparing enough for the whole world

Universal demand for a COVID-19 vaccine means production bottlenecks are a risk. For the Oxford vaccine, production involves growing key components in human embryonic kidney cells, before creating the actual vaccine and then purifying and then concentrating it. Running this process at industrial scale, say Qasim Rafiq and Martina Micheletti, is one of the biggest challenges AstraZeneca faces.

Tobacco – an unexpected ally?

Vaccines contain organic products, which traditionally have been grown using cell cultures in containers called bioreactors. Recently plants have been adapted to function as bioreactors too, which could help production be massively increased. Tobacco may be especially useful: it grows quickly, is farmed all over the world, is leafy and easily modifiable. The tech hasn’t been approved for mass producing medicines – but demand may change that.

Keeping vaccines cool will be crucial

Because COVID-19 vaccines will contain biological material, they’ll need to be kept cold right up until they’re delivered, explains Anna Nagurney. Fail to keep them cool and they’ll become ineffective. Refrigeration will therefore be a major challenge in any roll-out campaign; an estimated 25% of vaccines are spoiled by the time they reach their destination. A potential solution could be to encase their heat-sensitive parts in silica.

‘Vaccine nationalism’ threatens universal access

Some governments are signing agreements with manufacturers to supply them with vaccines ahead of other countries. Poorer nations risk being left empty handed – putting people at risk and preventing any attempt to coordinate suppressing the coronavirus worldwide. It’s also unclear how access is being priced in these deals.

How to counter vaccine nationalism

India can play a key role in avoiding this “richest-takes-all” scenario, says Rory Horner. It’s traditionally been a major supplier of medicines to the global south, and has the capacity to create more vaccines for COVID-19 than any other country in the world. India’s Serum Institute has signed up to make 400 million doses of the Oxford vaccine this year, but with a population of 1.35 billion, how many will go abroad isn’t yet clear.

Who will get the coronavirus vaccine first?

We need to plan now, say Laurence Roope and Philip Clarke. Governments have big decisions to make. The pandemic is akin to a war situation, so there’s an argument these vital goods should be rationed and banned from private sale. Authorities also need to decide who should be prioritised: those most vulnerable, people most likely to spread the virus, or those who can kickstart the economy by returning to work.


How do you counter resistance and scepticism?

Public resistance is a sizeable problem – but nothing new

Surveys show that one in four New Zealanders remain hesitant about a coronavirus vaccine, while one in six British people would refuse one. But vaccine hesitancy has been around for a long time, writes Sally Frampton. And Steven King argues the past – such as when smallpox vaccines were resisted – may provide some solutions to this problem.

Are anti-vaxxers a problem?

Not all hesitancy is the same, says Annamaria Carusi. As well as the hardcore anti-vaxxers, plenty may resist COVID-19 vaccines on safety or animal welfare grounds. Indeed, while anti-vaxxers attract a lot of attention, their influence on vaccination rates is often overstated, argues Samantha Vanderslott. In fact, desire for a vaccine is so widespread and strong that anti-vaxxer positions may be harder to defend right now.

The far right is exploiting the pandemic

A recent report from the United Nations Security Council warned that extreme right-wing groups in the US are using the pandemic to “radicalise, recruit, and inspire plots and attacks”. Blyth Crawford gives a run-down of the major groups at work in America – what their aims are, the methods they’re using to reach people, and the key pieces of misinformation that they’re peddling.

How to build trust in vaccines

The usual strategy is to double down on positive messaging. But a better strategy, Mark Honigsbaum argues, would be to acknowledge that there’s a lot we don’t know about how some vaccines work, but that the benefits of taking vaccines far outweigh the risks. A further step could be to make sure that manufacturers are liable should vaccine recipients suffer negative effects. Often manufacturers are exempt.


Looking ahead

The future is full of possibility. COVID-19, Sars, Mers and the common cold are all caused by coronaviruses, and scientists are considering whether it’s possible to create a vaccine that could offer protection against them all – and perhaps even against an as yet unknown coronavirus we’re yet to encounter. Admittedly, having a vaccine that can do this seems unlikely in the near future.

We shouldn’t get ahead of ourselves, though, says Sarah Pitt. No vaccine has yet completed its safety trials, and we can’t yet be sure that any vaccine will permanently prevent people from catching COVID-19. We need to prepare ourselves for the very real possibility that a COVID-19 vaccine only reduces the severity of symptoms or provides temporary protection.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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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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