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What scientists are doing to develop a vaccine for the new coronavirus – The Conversation Africa

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With an increasing number of confirmed cases in China and 24 other countries, the COVID-19 epidemic caused by the novel coronavirus (now known as SARS-CoV-2) looks concerning to many. As of Feb. 19, the latest numbers listed 74,280 confirmed cases including 2,006 deaths. Four of these deaths have occurred outside of mainland China: one each in the Philippines, Japan, Hong Kong and France. The case in France is the first COVID-19 death outside of Asia.

The World Health Organization (WHO) declared on Jan. 30 that the outbreak constituted a Public Health Emergency of International Concern.

In light of these events, health experts around the world are now divided as to whether this event will become a pandemic, or whether it will be possible to contain transmission of this virus.

Towards a pandemic?

In a recent New York Times article Dr. Thomas R. Frieden, former director of the Centers for Disease Control and Prevention, said it was “increasingly unlikely that the virus can be contained.” In the same article, Dr. Anthony S. Fauci, director of the U.S. National Institute of Allergy and Infectious Disease (NIAID), said, “It’s very, very transmissible, and it almost certainly is going to be a pandemic.”

On the other hand, the WHO remains optimistic. Its head of emergency responses, Dr. Michael Ryan, told STAT News, “there’s enough evidence to suggest that this virus can still be contained” and that “until [containment] is impossible, we should keep trying.”

This brings us to the scientists and experts who are doing just that, throwing everything they have at this public health issue. Some are focused on treating patients with existing or novel therapeutics, others are focused on stopping transmission between individuals by developing a vaccine. Luckily for scientists, lessons learned during the 2013-16 West African Ebola epidemic are now enabling the fast-track development of vaccines, without compromising their safety and efficacy.

Of course, it is critical to learn more about this specific novel virus, including its source and why transmission appears to be more efficient than with other coronaviruses.

Vaccine development

CEPI, the Coalition for Epidemic Preparedness Innovations, is an international, not-for-profit organization with the mandate of accelerating the development of vaccines against emerging infectious diseases. On Jan. 23, it announced financial support to three institutions for the development of a vaccine against the newly identified coronavirus: Inovio Pharmaceuticals Inc. and its “DNA platform,” the University of Queensland and its “protein clamp platform” and a Moderna Inc. partnership with NIAID using its “mRNA platform.”

On Jan. 31, CEPI also announced an extended partnership with CureVac, a biotechnology company, to adapt its RNA vaccine platform to SARS-CoV-2. Four days later, CEPI launched a call for proposals to develop new vaccines against the novel coronavirus, open to all organizations meeting its criteria and in possession of a readily available platform.

People wearing surgical masks sitting in the Shanghai metro in January 2020. The novel coronavirus that originated in Wuhan has spread to many cities in China.
(Robert Wei/Shutterstock)

Johnson & Johnson has also announced its participation in vaccine development, using its “adenovirus platform,” which consists of a virus that is modified to look like SARS-CoV-2, but is unable to cause disease in humans. GlaxoSmithKline, another large pharmaceutical company, recently announced a partnership with CEPI to offer access to anyone who would like to use its adjuvant platform (adjuvants are components that can be added to vaccines to increase the generation of an immune response).

Finally, adding its name to the list, the University of Hong Kong also announced it already had a vaccine, designed from a modified influenza virus vaccine.

Issues and solutions

But what do these platforms mean? Why are so many different organizations working towards the same goal of developing a vaccine against one pathogen? Wouldn’t it be easier if everyone worked together, instead of trying such a wide variety of approaches? The answers to these questions are not so simple.

Vaccine platforms are tools that scientists can use to develop a new vaccine, using a similar system to previously successful approaches. For example, one well-known and straightforward approach is the “inactivated platform,” where the pathogen is safely replicated in laboratories, inactivated and then administered as a vaccine.

Although these platforms use different approaches, they all have the same overall goal of training the immune system of the vaccinated individual to quickly recognize a pathogen inside the body.




Read more:
Coronavirus grown in lab outside China for first time, aiding the search for vaccine


So why are there so many different platforms? Well, each platform has its own advantages and disadvantages. Some are easier to mass produce, some are known to induce fewer side effects, and some are just better at training particular aspects of the immune system.

The human immune system is divided into two major arms: innate and adaptive. Our innate immune system is non-specific and provides an immediate, but limited level of protection against a foreign intruder inside the body. The adaptive immune system can target a specific pathogen, but needs time to develop its full effect, about 21 to 28 days following infection, or vaccination. The adaptive side can be further sub-divided into humoral and cellular immunity.

With new pathogens like SARS-CoV-2, scientists don’t know which sub-division of the immune system will provide protection, so they aren’t certain which platform will produce the most successful vaccine.

What are scientists doing then?

Vaccine design looks simple on paper, but making it work all the way to human use is a whole other story.

Currently, scientists are working on identifying which parts of SARS-CoV-2 they can use in their vaccines. These parts have to be carefully selected, because they need to mimic what a real infection would look like to our bodies. This has to be done in conjunction with selection of an appropriate vaccine delivery method: the platform that will be used.

Coronaviruses, like MERS CoV seen here, are named for their appearance under a microscope: projections give the edges of these viruses a characteristic corona, or crown-like shape.
(NIAID)

For ethical reasons, once a vaccine candidate is available, it needs to undergo safety and efficacy testing in animals (although exceptions are possible). Not all laboratory animals are susceptible to infection in the same way as humans. This is why scientists are also working to identify an animal model suitable for evaluating candidate vaccines. At this point, many months and tens of thousands of dollars have been invested in vaccine development.

Once animal trials are satisfactory, the vaccine can be administered to humans in a clinical trial to evaluate the vaccine’s safety and efficacy. This means additional months to years (if not decades), and millions of dollars in investment.

The last steps are often out of the scientists’ hands. The vaccine must be registered and receive regulatory approval, produced at large-scale and distributed. Although these steps take only a few lines to list here, they can take years to actually achieve.

On the other hand, health experts tell us over and over again that if we’re lucky and everything goes well, we could have a safe and effective vaccine in about a year. It remains to be seen at what stage of the process we will be in early 2021. If China has managed to build a 1,000-bed hospital in 10 days to counter the spread of the epidemic, who knows what can be achieved in a year on the vaccine side.

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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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