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COVID-19: Why high standards matter in developing coronavirus vaccine –



This article, written by Byram W. Bridle, University of Guelph; Samira Mubareka, University of Toronto, and Shayan Sharif, University of Guelph, originally appeared on The Conversation and has been republished here with permission:

Athletes understand that there are two very different approaches that can be taken when training their bodies. For example, lifting heavy weights is a great way to achieve maximum strength. In contrast, low-load high-repetition training is ideal for developing the stamina required for endurance sports.

Remarkably, our immune system can be trained in a somewhat similar fashion. It must choose between two different responses to dangerous pathogens, both of which lead to white blood cells called T cells and antibodies targeting the infecting microbe. However, the types of these T cells and antibodies is different depending on whether the pathogen lives outside of our cells, as many bacteria do, or inside our cells, as viruses do.

Mounting an anti-bacterial response against a virus may not be an ideal way to clear a viral infection. In fact, the wrong kind of immune response can actually exacerbate disease, as was observed in vaccinated mice challenged with the severe acute respiratory syndrome coronavirus (SARS-CoV) identified in 2003.

Importantly, our first exposure to a pathogen, either naturally or via vaccination, can train our immune system to adopt one of these two biases when we respond in the future to the same or a similar pathogen for the rest of our lives. Immunologists call this “trained immunity.”

First exposure

Our research programs span the fields of viral transmission, immune responses to viruses, respiratory pathogens such as influenza viruses and vaccine development, including vaccines against SARS-CoV-2, which is the causative agent of the coronavirus disease that emerged in 2019, COVID-19.

We would like to convey the importance of trained immunity in the context of COVID-19 vaccines since this can have implications for the ability of our immune systems to respond appropriately to highly pathogenic coronaviruses in the future.

Over the past 17 years, there have been three major outbreaks of highly pathogenic coronaviruses: the original SARS-CoV in 2003, Middle East Respiratory Syndrome coronavirus in 2012 and now SARS-CoV-2. Based on this history of having a new highly pathogenic coronavirus emerge approximately every decade, we should expect to have to deal with more of these viruses in the future. That means that the current drive to develop vaccines for COVID-19 should consider future coronavirus outbreaks.

The way we train our immune systems now to respond to SARS-CoV-2 could impact how well our bodies can respond to future coronaviruses. Vaccines, if developed properly, provide an opportunity to induce the type of trained immunity that is optimal for mounting protective immune responses, not only against SARS-CoV-2, but also against future infections with coronaviruses and/or their associated vaccines.

Tuberculosis response

Interestingly, some scientists have proposed to harness the concept of trained immunity in a related context. Specifically, there is evidence to suggest that individuals who received a vaccine against tuberculosis may be partially protected against SARS-CoV-2.

Tuberculosis is a respiratory disease caused by a bacterium. In contrast to many bacteria, this one, like viruses, lives inside cells. The vaccine formulation uses a live, but attenuated (modified or weakened) bacterium that is very similar to the one that causes the disease. Since it is a live bacterium, it can infect cells in the same way that the disease-causing bacteria do.

The result is an appropriate immune response that happens to be of the same type that is optimal against viruses. Scientists have concluded, therefore, that the tuberculosis vaccine might be training the immune system in such a way that it can respond ideally to other pathogens that live inside cells, including viruses like SARS-CoV-2.

Evaluating responses

A heavy emphasis is being placed on quantitative aspects of candidate COVID-19 vaccines, such as whether they generate high levels of antibodies. Many health regulatory agencies are poised to approve COVID-19 vaccines that reduce the burden of disease but do not induce immunity to completely prevent infection and transmission. But they should be cautious and ensure that these vaccines do not train our immune system for a response that is not optimal.

By thoroughly evaluating the nature and duration of the immune response induced by a prospective COVID-19 vaccine, we can ensure specific, effective and sustained responses against SARS-CoV-2. Specifically, vaccine developers should be able to answer these questions:

  1. Did the vaccine induce an immune response that is optimal against viruses? A balanced antiviral response should include antibodies to prevent the virus from infecting host cells and replicating inside them, and T cells to kill viruses that get past the antibody barrier. Importantly, the antibodies should be of antiviral types.

  2. Were there antibody responses in the respiratory tract, and do these antibodies efficiently neutralize the virus? There is significant focus placed on measuring antibody responses in the blood, but SARS-CoV-2 infects mucosal surfaces including the respiratory tract, and it is important to ensure that the vaccine induces antibodies at these relevant locations. Also, it must be noted that appropriate antibody responses against viruses are usually of much lower magnitude than those directed against extracellular bacteria. A large quantity of antibodies may seem promising, but the amount is not nearly as important as the types and locations of these antibodies.

The take-home message is that we should insist on maintaining a very high standard for a COVID-19 vaccine; one that will induce a qualitatively appropriate immune response that will protect us from infection with SARS-CoV-2.

Like an athlete, we need to avoid training our immune system in a way that contradicts the end goal. For long-term health, we must ensure that our immune systems are trained in a way that will allow us to respond most effectively against future highly pathogenic coronaviruses, some of which may prove to be more dangerous than the current one.

Byram W. Bridle, Associate Professor of Viral Immunology, Department of Pathobiology, University of Guelph; Samira Mubareka, Clinician-scientist, Laboratory Medicine and Pathobiology, University of Toronto, and Shayan Sharif, Professor of Immunology and Associate Dean, Research and Graduate Studies, University of Guelph

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

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Manitoba offers temporary $5/hour pay bump to staff helping vulnerable people –



Caregivers who provide direct or residential care to vulnerable Manitobans during the pandemic are being thanked with a pay bump.

The province will provide $5 per hour wage increase to eligible staff, including health-care aides, housekeeping staff, direct service workers and recreation workers, for a period of two months, Families Minister Heather Stefanson announced at a briefing Friday.

“This is really targeted at those lower-income folks that are working … frankly, as heroes within our system right now,” Stefanson said.

The $35-million caregiver wage support program will also support workplaces that are low on staff due to positive cases of COVID-19, she said.

Individuals at personal care homes or in disability services, child welfare services, homeless and family violence prevention shelters or long-term care facilities are eligible for the top-up. To qualify, workers must earn less than $25 an hour.

It’s expected as many as 20,000 workers can benefit.

Saluting front-line workers

“It recognizes the dedication and heroism of our front-line workers who are serving vulnerable Manitobans each and every day,” Stefanson said.

The program is partly funded by a $17-million commitment from the federal government. Ottawa’s contribution was part of money originally set aside for wage subsidies, an official said.

The top-up is based on the number of hours an employee works from Nov. 1 to Jan. 10. Regular and overtime hours are accepted. There is no limit to the amount of hours an eligible employee could apply for the wage bump.

Manitoba Families Minister Heather Stefanson announces a two-month wage subsidy for front-line care providers. It’s expected that 20,000 Manitobans will be eligible. (John Einarson/CBC)

Applications will be accepted twice. The first intake period will close on Dec. 14 and the money will be paid directly to workers that week, the province said. Applications will also be received in the second week of January. 

A full-time worker could receive an extra $1,800, the province said.

Shannon McAteer, health care co-ordinator for the Canadian Union of Public Employees Manitoba, said the extra $5 an hour will supplement the incomes of people who need it.

“This also highlights the fact that this this category, this sector … is definitely underpaid,” McAteer said, and that was the case even before the pandemic. The pay scale in some positions doesn’t go much higher than minimum wage, she said.

Some workers in this sector only have a few days of sick pay, said McAteer. She’d like to see additional funding for support workers who get sick with COVID-19 or must isolate.

Meanwhile, Stefanson described the wage subsidy announcement Friday as a first step toward helping employees already working in the sector. 

She didn’t say, however, how facilities are coping with limited staffing. Stefanson said 16 Community Living disABILITY Services agencies have reported positive COVID-19 cases among participants or staff.

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B.C. sees new daily high of 911 COVID-19 cases, reports 11 deaths – News 1130



VANCOUVER (NEWS 1130) — As the province’s second wave pushes new COVID-19 cases and hospitalizations to new records on a nearly daily basis, health officials are urging British Columbians to keep each other safe.

Provincial Health Officer Dr. Bonnie Henry announced 911 new infections Friday, pushing B.C. over the 30,000 mark of confirmed cases since the pandemic began.

It is also another day deaths were in the double digits, with 11 more people losing their lives to COVID-19.

Henry said she’s concerned about recent reports of aggression over mask wearing, where employees have been assaulted or confronted over the order.

“Please remember that this requirement to wear a mask in indoor public locations is a provincial order that everyone must follow,” she said, while comparing masks to seatbelts and helmets. “It’s a layer of protection for everybody and a courtesy to those around you. And if you are opposed to wearing a mask, then I asked you to shop online, order takeout, or stay home and not put other people at risk.”

RELATED: Burnaby couple confronted by maskless neighbour over COVID-19 rule

She again offered a reminder that we don’t always know each other’s story, and we need to show each other respect.

“We have people who are suffering in our hospitals, right now, and their families are suffering too. And that these small simple actions, make a big difference for all of us,” Henry added.

There are a record 301 patients currently hospitalized, with 69 of them in intensive care.

While Health Minister Adrian Dix assures there is enough capacity in acute care, there is still the challenge of having ample staffing and resources.

“We do for the moment, but it is important, I think, for everyone to understand how critical is for those waiting for other procedures and for everyone that we do everything we can to stop the spread over the last number of days as well.”

Given there are more than 10,000 people under public health monitoring because they’re been in close contact with an infected person, nearly 8,000 active cases, and rising daily infections, Henry reminded British Columbians that there can be a delay in receiving a negative test result.

“Public health teams may conduct, or may ask and offer widespread testing of people whether symptomatic or asymptomatic in settings like workplaces like schools and long-term care homes even if there’s not widespread community transmission in that area. The priority is to contact those who are positive first to make sure that people are isolating so there may be a delay in people getting results,” she explained.

Meanwhile, three more outbreaks in health-care facilities were reported at the German-Canadian Benevolent Society, Villa Cathay Care Home, and Morgan Place Care Home. The Peace Portal Senior Village outbreak has ended.

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N.B. could have COVID-19 vaccine by January. Now comes deciding who gets it first –



All things considered, it’s a good problem to have: eight months into managing the COVID-19 pandemic, Public Health officials in New Brunswick now must start sorting out who to vaccinate first.

It won’t be easy, given that the number of New Brunswickers old enough to be considered high-risk far exceeds the number of doses coming in the first wave of vaccines early next year. 

The province could receive enough doses for 60,000 people early in January. 

But the number of people over the age of 60 — the point at which the risk of serious COVID-19 impacts increases dramatically — is more than 200,000.

Chief Medical Officer of Health Dr. Jennifer Russell said choosing who will be at the front of the line will be a complicated calculation.

“That’s the point of prioritizing,” she said. “We know there’s not going to be enough, and this is going to be the most complex immunization program ever delivered in this country and around the world.” 

Chief Medical Officer of Health Dr. Jennifer Russell says choosing who will be at the front of the line will be a complicated calculation. (Submitted by the Government of New Brunswick)

Federal distribution plan based on population

The federal government has agreed to distribute the first batch of vaccines, due in the first three months of 2021, using a formula roughly based on population.

With enough doses for three million people, that would translate into about 60,000 New Brunswickers vaccinated by April.

Russell said she and her counterparts federally and in other provinces have agreed on a general plan that will be hammered into place in time for expected regulatory approval of the first vaccines next month. 

Distribution could begin as early as January. 

“I think long-term care nursing home facilities would be priority one, certainly, as a very vulnerable section of our population,” said Premier Blaine Higgs.

The New Brunswick Association of Nursing Homes said there are 4,800 beds in its member homes.

“I think you would move quickly into the health-care workers and protecting them, and then the likely next step would be seniors,” Higgs said.

Premier Blaine Higgs thinks long-term care nursing homes would be ‘priority one’ for getting the vaccine in New Brunswick. (CBC News file)

Nursing home workers would account for 4,800 doses

First responders would also be near the top of the list, Higgs said.

“And then you just kind of work through the age demographics.”

Vaccinating unionized nursing home workers around the province would require more than 4,800 doses.

That’s how many members of the Canadian Union of Public Employees work in more than 50 nursing homes, according to union spokesperson Simon Ouellette. 

Vulnerable people should be prioritized, but so should the people who work with them.– Simon Ouellette, CUPE spokesperson

Five long-term care or nursing homes have been hit by outbreaks in New Brunswick.

Some nursing home workers, including maintenance and cleaning staff, must move from room to room, creating the risk of becoming a super-spreader, Ouellette said.

“Vulnerable people should be prioritized, but so should the people who work with them.”

There are also 1,875 doctors in the province, according to Dr. Jeff Steeves, president of the New Brunswick Medical Society. The New Brunswick Nurses Union estimates 6,400 nurses are in the workforce now.

Those doctors include emergency department and critical care physicians who are potentially exposed to COVID-19 frequently.

“Those most exposed to those being ill are going to need it first,” Steeves said.

New Brunswick Medical Society president Dr. Jeff Steeves says ER doctors and critical care physicians are potentially exposed to COVID-19 frequently and so should be among the first to get the vaccine. (New Brunswick Medical Society)

People with chronic conditions on high-priority list

And there are 950 ambulance paramedics who are “seeing folks that they don’t have a really good understanding of when they initially respond about what may or may not be wrong with them,” said Chris Hood, executive director of the Paramedic Association of New Brunswick.

“The association feels strongly that to protect the members, who are obviously in short supply, and to protect the public that they serve, they should be one of the first groups to be done,” he said.

Russell said New Brunswickers with chronic conditions are also “somewhere on that list” of high-priority patients.

According to the New Brunswick Health Council, 11.6 per cent of adults in the province have been diagnosed with asthma and 11.4 per cent have been diagnosed with diabetes, two conditions that COVID-19 can quickly make life-threatening.

Russell said Indigenous people will also be a high priority because COVID-19 has had a disproportionate impact on them.

But it’s possible the federal government, which has responsibility for Indigenous issues, will hang on to a small percentage of vaccine doses and do that itself, along with immunizing some military members and federal inmates.

She said the goal is to have 75 per cent of the province vaccinated, enough to create herd immunity in the population. She doesn’t see that happening until next fall or later.

Education and Early Childhood Development Minister Dominic Cardy said he would support immunizing school children soon after the high-priority groups are done. (Submitted by the Government of New Brunswick)

Cardy wants schoolchildren to follow high-priority groups

Higgs said Thursday that the fact some people will want to wait to ensure the vaccines are safe could make the process easier.

“There’s a number of people that want to be vaccinated early, and there are probably others that want to kind of wait a bit,” he told CBC’s Power and Politics. “So it may not be a rush to the front of the line immediately.”

Last week Education and Early Childhood Development Minister Dominic Cardy said he would support immunizing schoolchildren soon after the high-priority groups are done. 

“We’re seeing, unfortunately, in the last few months, a significant increase in the number of young people who are becoming not just infected with COVID-19 but are then passing it on,” he said.

“Younger people get less sick, but they can be just as efficient a disease vector as anyone of any age, so I’d certainly argue that. I think that would make sense.”

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