I’m over 50 and can now get my COVID vaccine. Is the AstraZeneca vaccine safe? Does it work? What else do I need to know?


from www.shutterstock.com

Meru Sheel, Australian National University; Cyra Patel, Australian National University, and Margie Danchin, Murdoch Children’s Research InstituteFrom today, Australians aged 50 or older are eligible to receive their COVID-19 vaccine from special respiratory clinics or mass vaccination hubs in some states. Appointments with selected GPs are available from May 17.

However, a recent poll shows many people over 50 are hesitant to get vaccinated, particularly with the AstraZeneca vaccine earmarked for them. That’s mostly due to reports of very rare, but serious, blood clots that can develop after vaccination.

So it’s understandable why people want to know about any safety issues and how they relate to age. It’s also natural to want to know how well the vaccine works to protect people over 50.

Here’s what we know about this safe and effective vaccine from clinical trials and around 136 countries using it so far.

Does the AstraZeneca vaccine protect people over 50?

Clinical trials, which have included more than 57,000 people to date, found the AstraZeneca vaccine to be safe and effective.

When researchers pooled the results from four large trials — including about 8,600 vaccinated people and a similar number of unvaccinated persons — there were 81% fewer COVID-19 cases in vaccinated people than in unvaccinated ones. No one who got the vaccine was hospitalised due to COVID-19.

While the studies haven’t been designed specifically to look at efficacy in distinct age groups yet, there is good evidence the AstraZeneca vaccine protects both the elderly and younger adults from COVID-19. In clinical trials, adults aged 18-55 and those older than 55 had similar immune responses.

How about serious disease and death?

When it comes to protecting people from serious disease, there’s good news again. We have data from England and Scotland that one dose of it reduces COVID-19 hospitalisations by 80-88% in the elderly, similar to that of the Pfizer vaccine (88-91%).

Based on our understanding of how vaccines work — generally, vaccines are more effective in younger adults — it’s safe to assume the vaccine is at least 80% effective in preventing severe COVID-19 in people over 50.

Emergency sign
We want to avoid people ending up in hospital with serious COVID-19. With the AstraZeneca vaccine, hospitalisations are down around 80%.
from www.shutterstock.com

What about the new variants?

New variants of SARS-CoV-2, the virus that causes COVID-19, affect the efficacy of the AstraZeneca vaccine, but only slightly for the B.1.1.7 strain (the UK variant). It’s about 70% effective against this strain, compared with about 82% for the original strain.

However, there have been some concerns about protection against the B.1.351 strain (the South African variant). This is because the AstraZeneca vaccine provides less protection against mild COVID-19 disease in people infected with it.

Does the AstraZeneca vaccine limit spread of COVID-19?

We still need more long-term data to say for certain whether the vaccine prevents transmission of COVID-19.

However, preliminary UK research provides some welcome news. Researchers looked at more than 365,000 households and nearly one million contacts of COVID-19 cases. They found the vaccine reduced transmission from people vaccinated with one dose by 40-50%. This is great news in terms of slowing the spread of the disease.

How safe is the AstraZeneca vaccine in people over 50?

Both clinical trials and real-world data confirm the AstraZeneca vaccine has a good safety profile similar to other vaccines commonly used in Australia.

Side-effects are common and are mostly mild to moderate, with few recipients needing medical attention. The most common are reactions at the injection site, fatigue, headache and muscle pain. These occur in half to three-quarters of people under 55 after their first dose, and are less common in older people. The side-effects generally start within 24 hours and last around one or two days, and indicate your immune system is working.

In Australia, data from the AusVaxSafety vaccine surveillance system shows about 22% of people vaccinated with the AstraZeneca vaccine missed a day or more of work or studies as they were unwell. Fewer than 2% needed to see a doctor.




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What about the blood clots I’ve been hearing about?

Serious reactions to the vaccine have been very rare, one of which includes thrombosis with thrombocytopenia syndrome, which is on everyone’s mind right now.

This is a very rare condition in which blood clots (thrombosis) and low levels of platelets (thrombocytopenia) occur 4-28 days after receiving the vaccine. This can lead to disability and 20-25% of people with these clots die.

About six in every million people vaccinated with the AstraZeneca vaccine develop the condition. And it tends to be more common in people under 50. Other than younger age, there are no other risk factors for these clots we know of yet.

In Australia, there have been six cases of this type of blood clotting: one person in their 30s, four in their 40s, and one in their 80s. Of these, a person in their 40s has died from it.




Read more:
What is thrombocytopenia, the rare blood condition possibly linked to the AstraZeneca vaccine?


As Australia is largely COVID-free, is it worth me getting the AstraZeneca vaccine?

The risk-benefit analysis for Australians right now differs depending on the amount of COVID-19 in the community, your age and the availability of alternative vaccines.

Based on a small amount of data so far, the risk of these blood clots after the AstraZeneca vaccine, for people aged 50-59 is about 0.4 per 100,000 and for those aged 60-69, 0.2 per 100,000.

But the risk of getting severe COVID-19 or the risk of admission into intensive care from COVID-19 is much higher for the over 50s — nearly ten-fold higher than the risk of clots after the vaccine.

It’s about 6.5 per 100,000 people aged 50-59 and 7.0 per 100,000 for people aged 60-69, based on data from Victoria’s second wave in July 2020. There are different risk-benefit calculations for different scenarios.

In a scenario similar to the second wave of COVID-19 in Victoria, the risk of ICU admission due to COVID-19 is much higher than the risk of blood clots from the AstraZeneca vaccine.
from the Australian Government Department of Health

Australia has almost no disease in the community. However, this could change very quickly if there were new outbreaks. We also have no alternative to the AstraZeneca vaccine for most people over 50 (more Pfizer vaccine is not available until the last quarter of 2021). So balancing the risks and benefits of the vaccine, is extremely challenging. People may not perceive their risk of COVID-19 as high enough to warrant vaccination and are preferring to wait, perhaps six months or more until other vaccines are available.

However, the potential benefits of the vaccine go far beyond what we’ve already mentioned. Vaccination will contribute to the prevention of long COVID-19 (symptoms that linger for months) as well as increased ability to move around freely in society, including being able to attend large events. Vaccination will help us avoid lockdowns or school closures, allow us to travel overseas and return to normal life.




Read more:
A balancing act between benefits and risks: making sense of the latest vaccine news


How do I get vaccinated?

You can use the government’s vaccine eligibility tracker to check whether you can receive your COVID-19 vaccine from today, and to make an appointment.

This will give you details of the state- and territory-run vaccination clinics near you that are open from today (not all are taking appointments for the over 50s yet). From May 17, you can receive your vaccine at some GP clinics.

Two doses of the AstraZeneca vaccine are needed for best protection, preferably 12 weeks apart.The Conversation


Department of Health/The Conversation, CC BY-ND

Meru Sheel, Epidemiologist | Senior Research Fellow, Australian National University; Cyra Patel, PhD candidate, Australian National University, and Margie Danchin, Paediatrician at the Royal Childrens Hospital and Associate Professor and Clinician Scientist, University of Melbourne and MCRI, Murdoch Children’s Research Institute

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

3 doses, then 1 each year: why Pfizer, not AstraZeneca, is the best bet for the long haul


Nathan Bartlett, University of NewcastleLast week, the chief executive of Pfizer said anyone who receives its COVID-19 vaccine will probably need to have a third dose within 6-12 months after being fully immunised, and then likely one dose every year going forward.

We’ll need these because it’s likely that, for many of us, immunity will begin to wane within that time frame. The vaccine will also need to be tweaked to cover new coronavirus variants as they emerge.

The advantage of mRNA vaccines like Pfizer’s is they’re much easier to update than the “viral vector” vaccines like AstraZeneca’s. We should still use AstraZeneca now for over-50s, but our best long-term strategy is to use mRNA COVID-19 vaccines, and therefore to develop the capacity to manufacture them here in Australia.

Immunity to coronaviruses doesn’t last

We know our immunity to different coronaviruses wanes over time. This is true for the four common cold (endemic) coronaviruses that circulate all the time — there are always sufficient numbers of people who have lost their immunity to ensure these viruses can persist and continue to cause respiratory illnesses.

Our immunity to SARS-CoV-2, the virus that causes COVID-19, also seems to wane quickly, although the rate at which this happens can be quite variable. Data suggest immunity acquired from the Pfizer shot is pretty robust for six months, but it isn’t clear how quickly our immunity is lost after that. However, it’s reasonable to predict that within 12 months of a population being vaccinated, a substantial number of people will have likely lost protection against SARS-CoV-2. This will particularly be the case if the prevalent SARS-CoV-2 strain circulating at that time is substantially different from the virus against which people were originally vaccinated.

This relates to the fact that some coronavirus variants have mutations that reduce the effectiveness of vaccine-induced immunity. They’ve been described as “variants of concern” and include a virus that originated in South Africa, which has reduced the efficacy of both the AstraZeneca and Pfizer vaccines. As the pandemic surges around the world, more variants will certainly crop up.

Both waning immunity and viral variants will conspire to reduce our protection over time. So we’ll need booster shots, ideally updated to deal with the viral variant that poses the greatest threat.

Using AstraZeneca is not our best long-term solution

I understand why Australia’s government originally prioritised getting the AstraZeneca vaccine. It’s easier to manufacture, store and distribute. It made sense in the early stages of the pandemic. And it’s still an effective vaccine that people, here and abroad, should be receiving as soon as possible — any immunity is better than none and you will certainly be protected from severe COVID-19.

But as time goes on, using the AstraZeneca shot isn’t the best long-term strategy.

One reason for this is what immunologists call “vector immunity”. The AstraZeneca and Johnson & Johnson vaccines use a viral vector, which is an inactivated (cannot replicate) form of a common type of virus called an “adenovirus”. They use this adenovirus as a delivery vehicle to get DNA into our cells to give them the instructions to develop immunity against the coronavirus. However, you can’t be repeatedly immunised with this type of vaccine because you’ll likely develop immunity to the adenovirus vector (the delivery vehicle) itself. When that happens your immune system interferes with the delivery vehicle getting into your cells and the effectiveness of these vaccines would erode over time.

What’s more, in a very, very small number of people, this viral vector seems to be linked with an extremely rare but serious blood clotting syndrome. In these people, it’s thought that a consequence of the immune response to the viral vector is their immune systems make “auto-antibodies”. These are antibodies that, in addition to fighting a foreign invader (or targeting the adenovirus-based vector used in the AstraZeneca vaccine), also attack our own cells. In this case, these auto-antibodies are attacking blood cells called platelets, leading to the blood clots and low platelet counts seen in around 1 in 250,000 people vaccinated with the AstraZeneca shot.

There are also clotting concerns with the Johnson & Johnson vaccine, which is also an adenovirus-vector-based vaccine, after six women developed the condition in the United States out of 6.8 million given the shot. However, this link is yet to be proven for this vaccine.




Read more:
What is thrombocytopenia, the rare blood condition possibly linked to the AstraZeneca vaccine?


By contrast, mRNA vaccines like Pfizer’s (and Moderna’s) can be updated much more quickly. Pfizer just needs to rework its RNA sequence to cover variants, which is a minor modification. Nothing changes about the delivery system of the vaccine, so reapproval will likely be much easier. Regulatory bodies have indicated there will be a quick path for approval for vaccines updated for variants.




Read more:
Why we’ll get COVID booster vaccines quickly and how we know they’re safe


The mRNA vaccines consist of a lipid-based delivery system that protects the mRNA and gets it into cells. Then, the cells can start manufacturing the spike protein to present to your immune system. There’s no protein in the vaccine itself, so there’s no chance of developing immunity to the vaccine components.

mRNA vaccines are our best bet going forward

There’s a fear among researchers, including myself, that we’ll be chasing our tails with these new variants. We’ll identify a new variant and set out to update our vaccines against it, but by the time the formulation is updated, approved, manufactured and distributed, we may already be dealing with another variant, or many variants across different locations.

It’s absolutely vital Australia develops the ability to make mRNA vaccines onshore, particularly if new variants pop up here or in our region. This will be far more effective than waiting months to get new shots from overseas.




Read more:
Australia may miss out on several COVID vaccines if it can’t make mRNA ones locally


Federal health minister Greg Hunt has indicated Australia is interested in developing this capacity.

Right now, the AstraZeneca vaccine still has a role in Australia’s current vaccine strategy. We have it and we can make more of it, so let’s get it out there for over-50s as well as give those under 50 the opportunity to make an informed choice to have this vaccine.

So few Australians currently have immunity to the virus, we remain vulnerable to outbreaks. If there are new outbreaks, we would have to rely on lockdowns, masks and other strategies again, and could find ourselves back to where we were last year. And let’s not forget people will become ill and some will die. The vaccine rollout is lagging, and we really need to catch up as soon as possible.

But as time goes on, the AstraZeneca vaccine will become less attractive, and mRNA vaccines such as Pfizer’s should eventually take its place.The Conversation

Nathan Bartlett, Associate Professor, School of Biomedical Sciences and Pharmacy, University of Newcastle

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

Doctors do not face a greater legal risk if they give AstraZeneca to younger Australians — here’s why


Simon Santi/AAP

Cameron Stewart, University of SydneyLast week, the federal government changed its recommendation for COVID-19 vaccines. The Pfizer vaccine is now the “preferred” jab for adults under 50.

Amid the political fallout and worries about what it means for Australia’s COVID recovery, doctors have expressed concern about their liability. Some said they would even stop giving the AstraZeneca jab until they were more certain of their position.




Read more:
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Are they at greater legal risk if they give AstraZeneca to younger Australians? The government insists they are not. This is correct — here’s why.

Proving fault

In Australia, medical liability is, for the most part, fault-based. This means patients who are injured by medicines, medical devices and medical interventions must prove the doctors who used them were to blame for any injury they suffered before any compensation will be paid.

Australian liability laws are state-based, but generally speaking, fault can only be proven when the doctor has acted outside of the professional standard of care in a way that is not supported widely in Australia by professional peers.

What is the standard of care?

The standard of care for diagnosis and treatment is effectively set by the medical profession. In cases — such as COVID vaccines — where the treatment is new and knowledge about the treatment is emerging, the standard of care is also developing.

Importantly, doctors are judged by measuring their behaviour against the standard of care at the time the treatment was given. This means that if, in 2020 a doctor administers a COVID vaccine in a way that was supported by their peers at that time, they will not be found to have breached the standard of care if, years later, other side effects become known.

Prime Minister Scott Morrison inspecting AstraZeneca production.
Last week the Morrison government changed its advice around the AstraZeneca vaccine.
David Caird/AAP

We should also be careful not to automatically equate the government’s advice concerning the AstraZeneca vaccine with what the standard of care should be at the individual level.

The government’s advice is concerned with the big picture and with risks across a population. Doctors have the task of treating individuals. So, the government’s advice should be considered by doctors when working out which vaccines to offer to patients, but there may well be situations where the AstraZeneca is the best option for individual adult patients under 50.

Giving advice and accepting risks

Doctors also have a duty to inform individual patients about material risks of the treatments they provide. Every intervention comes with a set of risks but only the material ones need to be disclosed.

Material risks include those the profession would usually notify patients of (objective material risks), as well as risks the individual patient may have a particular concern about (subjective material risks).

The classic example of this is the 1993 case of Rogers v Whitaker where a woman who was blind in one eye was considering cosmetic surgery on that eye. She was concerned about any risk (no matter how remote) of going blind in her “good eye”. Later, she became blind from a complication of her treatment, which was known but very rare. The doctor’s failure to inform her was considered a breach of the duty to inform — even though it was not a risk normally disclosed — because the risk was subjectively material to her.

Again, the doctor will always be judged by what the profession knew at the time regarding these risks. If a patient is told about the material risks of the treatment and decides to go ahead with the treatment, the doctor has satisfied their legal duty to advise and cannot be held liable for subsequent injuries.

What now for GPs and AstraZeneca?

As long as doctors consider the government advice, keep up with professional news about best practice and communicate material risks to patients, they face no greater liability for providing COVID vaccines than they do for any other treatment.

The reality is the risks of people being injured by vaccines, and of doctors being sued for vaccine-related injury, is incredibly low.

At the weekend, the Australian Medical Association also said if a patient makes an informed decision to receive the AstraZeneca vaccine, GPs are protected under professional indemnity insurance.

Of course, the reality of low risk may not match the fear practitioners experience. So, are there things we can do to reduce the anxiety practitioners feel regarding liability?




Read more:
Bad reactions to the COVID vaccine will be rare, but Australians deserve a proper compensation scheme


One obvious measure is to move to no-fault systems of compensation. Many countries including the United States and New Zealand have no-fault compensation schemes for vaccine-related injury. Putting such a scheme in place may very well help doctors get over the fear of being sued. It might also give patients confidence knowing that in an extremely rare case of injury, they will be covered.

This could be done either with a one-off scheme or by expanding the National Injury Insurance Scheme, which covers personal injuries from motor vehicle accidents.

Without such schemes, Australian patients will only have access to compensation for vaccine-related injury if they can prove it was caused by a failure to act according to medical standards of care or a failure to properly inform the patient of material risks.The Conversation

Cameron Stewart, Professor at Sydney Law School, University of Sydney

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

Is it the adenovirus vaccine technology, used by AstraZeneca and Johnson & Johnson, causing blood clots? There’s no evidence yet


Kylie Quinn, RMIT UniversityThis week, US health authorities recommended pausing the rollout of the one-shot Johnson & Johnson/Janssen COVID-19 vaccine while investigations into exceptionally rare blood clots take place.

Six women suffered blood clots out of nearly seven million doses administered.

The J&J vaccine uses broadly similar vaccine technology as the AstraZeneca vaccine, known as adenoviral vectors, which has led some experts to speculate there might be a link between this vaccine platform and the very rare blood clotting condition known as “vaccine-induced immune thrombotic thrombocytopenia” (VITT).




Read more:
What is thrombocytopenia, the rare blood condition possibly linked to the AstraZeneca vaccine?


So far, a link between adenovirus technology in general and blood clots is purely speculation — there’s no evidence yet — but it’s worthwhile for health authorities to assess the data and for researchers to try to understand:

  • can adenoviral vectors in general cause VITT?
  • is VITT specific to the AstraZeneca adenoviral vaccine?
  • are certain unlucky individuals pre-disposed to develop VITT?

So what’s an adenovirus, and how are they used in vaccines?

Adenoviruses are a large family of viruses found in humans and other animals. In humans, some of these viruses can cause the common cold.

Scientists can also use these viruses to make vaccines, by using them to make what’s called a “viral vector”. A vector is a virus shell that researchers can use to package up and deliver a target from another virus.

To make an adenoviral vector, scientists take an adenovirus and remove any genetic material that could either allow the virus to replicate and spread, or cause disease. Researchers then take the adenovirus shell and insert genetic instructions for how to make a target on the surface of another virus. For COVID-19, they use the instructions to make the “spike protein” on the surface of the SARS-CoV-2 virus.




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From adenoviruses to RNA: the pros and cons of different COVID vaccine technologies


To your immune system, an adenoviral vector looks like a serious virus, even though it can’t replicate or cause disease. As a result, your immune system mounts a serious response, which is why people have been reporting more noticeable side-effects like a fever, fatigue and sore arm in the couple of days after the vaccine.

Similar but different

Currently, four COVID-19 vaccines use adenoviral vectors: AstraZeneca, Janssen/Johnson&Johnson, CanSino Biologicals and Sputnik V.

There are many adenoviruses out there to use as a starting point to make different adenoviral vectors. While these vectors can share some characteristics, they can also be biologically pretty different.

Different adenoviruses use different access points, known as receptors, to get into our cells. This can result in a very different size and type of immune response. Also, the adenovirus used in the Sputnik V and CanSino vaccines, called “rAd5”, isn’t very good at setting off the alarms in our immune system, while other adenoviral vectors are better.

The different vaccines also deliver slightly different sets of instructions for the spike protein. The J&J vaccine, called “rAd26”, instructs our cells to make a spike protein that’s locked into a specific shape, to help our immune system recognise it, and it’s delivered to the surface of the cell. The AstraZeneca vaccine, called “chAdOx01” instructs the cell to make a spike protein that isn’t locked in place and it can be secreted from the cell.

Given these differences, if one adenoviral vaccine is linked with a particular effect in our bodies, for example blood clots, it doesn’t mean all vaccines in this family will have that same effect. But regulators should still investigate.

We need to understand more about these blood clots

A number of regulatory bodies have issued notifications of a plausible link between the AstraZeneca vaccine and VITT.

This risk is very, very low — around one in 200,000 people that receive the vaccine could develop the condition. But for the rare person that develops VITT, the consequences can be serious, with around one-quarter of those with the condition dying from it. So regulators are taking the situation seriously.

VITT isn’t like other clotting conditions. There are many different types of clotting conditions but it seems VITT is likely to be caused by an unusual immune response.

We don’t know exactly what triggers this immune response. There have been reports of clotting conditions with adenovirus infections or very high doses of adenoviral vectors. However, this occurred very quickly, while VITT is a delayed response, observed 4-20 days after vaccination. It seems more likely at this stage that, in certain very rare patients, some kind of unusual immune response may be triggered.




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While researchers try to understand VITT, many regulators are taking a cautious approach — advising their communities, giving guidelines for preferred vaccines with younger age groups and revisiting data for other vaccines to be vigilant.

In doing this, regulators must balance a very rare risk of VITT with the AstraZeneca vaccine, with a very real risk of death and disease that face people with COVID-19. For many people, particularly older people in regions with community transmission of the virus, it still makes clear sense for their health to receive whichever COVID-19 vaccine is available.

These are complex decisions resulting in nuanced information that is hard to communicate. But the fact regulators are engaging with them quickly and transparently has been reassuring to me and, I hope, others in our broader community.The Conversation

Kylie Quinn, Vice-Chancellor’s Research Fellow, School of Health and Biomedical Sciences, RMIT University

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

New AstraZeneca advice is a safer path, but it’s damaged vaccine confidence. The government must urgently restore it


Jane E Frawley, University of Technology SydneyThe federal government’s recommendation last week that the Pfizer COVID-19 vaccine is now the preferred vaccine for adults under 50 has shaken public confidence in the COVID-19 vaccine rollout.

The Australian Technical Advisory Group on Immunisation (ATAGI) advised the AstraZeneca vaccine, previously planned as Australia’s main vaccine, will no longer be the preferred vaccine for adults under 50. It came after an extensive review of data from the United Kingdom and Europe which found an association between a very rare type of blood clot and the AstraZeneca vaccine.

Public confusion has already resulted in mass cancellations of vaccine appointments at GP clinics, by adults both over and under 50.

It’s important to remember the Australian government can afford to choose a safer path because we are not in the midst of a large COVID-19 outbreak.

But a decrease in vaccine confidence may be an unintended consequence of this path.

Now, the federal government must urgently restore public confidence in the vaccine rollout. It needs to quickly reassure adults aged over 50 the AstraZeneca vaccine is safe.

It’s essential the government gets this right. Concerns about one vaccine can damage public trust in other vaccines.

Why has a safer approach decreased confidence?

Vaccine confidence can be fickle. There are many recent examples of established vaccine programs that have been undermined by unrelated events or errors. This has led to mass disease outbreak and preventable death. For example, in the Philippines, a new measles outbreak that infected 47,871 people in 2019 and killed 632, mostly children, was fuelled by a drop in measles vaccination spurred by concerns about a dengue fever vaccine.

Vaccine program resilience is an even bigger ask during a new vaccine rollout where rare effects are expected once the vaccine is given to hundreds of millions of people.

Research from the Australian National University published last week found young women are the most likely to avoid vaccination. Women who did not approve of the government’s handling of recent sexual harassment scandals were less likely to accept a COVID vaccine. This demonstrates the importance of trust, and shows a lack of trust in one area of the government’s remit can spill into other areas.

Because the risk of catching COVID-19 is currently so low in Australia, many people are feeling less interested in being vaccinated.

One Australian study, published in September last year, found fewer people were willing to accept a COVID-19 vaccine compared to a similar study done two months earlier. This decrease was evident following a decreased number of new COVID-19 cases in Australia in the time between these two studies. People can change their intention to be vaccinated when they fear the effects from the vaccine more than the disease.

On top of all of this, some members of the community are still concerned COVID-19 vaccines were developed too quickly and without appropriate checks and balances — even though this isn’t true.

Changing recommendations during a vaccine program rollout can compound these concerns.




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How can confidence be restored?

While the federal government was quick to accept the recommendation from ATAGI, the confusion has added to the rollout chaos. Public confidence has been damaged, and further vaccine delays are imminent across the board, including for younger health and aged-care workers.




Read more:
4 ways Australia’s COVID vaccine rollout has been bungled


Vaccine program resilience is essential to survive the bumps along the way and the government has not invested enough in understanding public sentiment and developing plain language information resources.

The challenge for public health and the federal government now is to address the understandable concerns and prevent them from contaminating the broader public dialog on COVID-19 vaccination.

With high numbers of Australians needing to be vaccinated to prevent further COVID-19 outbreaks, there’s very little room for vaccine rejection.

The government urgently needs to use clear messaging for all communities and health professionals. This includes communities with diverse cultural and language requirements

These efforts will greatly benefit from multidisciplinary teams of infectious disease, vaccine, social science and communication experts.

We need a compensation scheme

During Australia’s COVID-19 vaccine rollout, so far one man in his 40s has developed blood clots following vaccination with the AstraZeneca vaccine. There’s a 25% death rate following a vaccine-related clot according to ATAGI. Four to six clots are expected per million doses of AstraZeneca vaccine (first dose) and while this reaction is exceedingly rare, it is severe.

This also highlights the importance of a no-fault vaccine injury compensation scheme.

Such a scheme recognises that if the government promotes whole of community vaccination for collective good, then it also accepts the ethical and financial burden for the few people who will sustain a serious injury. The federal government should implement one as a matter of priority.




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Bad reactions to the COVID vaccine will be rare, but Australians deserve a proper compensation scheme


The Conversation


Jane E Frawley, NHMRC Research Fellow, University of Technology Sydney

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

A balancing act between benefits and risks: making sense of the latest vaccine news


Shutterstock

Hassan Vally, La Trobe UniversityLast night, the federal government announced substantially revised plans for the use of the AstraZeneca vaccine in Australia.

Due to concerns about the vaccine’s possible links to a rare blood-clotting disorder, and following advice from the Australian Technical Advisory Group on Immunisation (ATAGI), the Pfizer vaccine is now preferred for people under 50.

These developments raise questions about how authorities and individuals assess risk, and respond. Let’s try to make some sense of it.




Read more:
New setback for vaccine rollout, with AstraZeneca not advised for people under 50


What’s happened?

Reports about rare blood clots possibly associated with the AstraZeneca vaccine have been floating around for a few weeks now.

So why has it taken so long for the government to clarify this relationship and make the recommendations? Authorities haven’t been keeping us in the dark.

When you have a new condition like this, and experts are examining data in real time, it takes a while to understand exactly what’s going on: to develop a clear case definition, to be confident what you’re seeing is a real phenomenon, and importantly, whether it’s likely to be caused by something in particular (in this case, the vaccine). It’s made more difficult when the event is very rare.

After reviewing a wide range of data relating to cases of this rare blood-clotting syndrome predominantly in the United Kingdom and Europe, Australian experts have now reached the threshold of evidence they needed to be satisfied there may well be a causal link between the AstraZeneca vaccine and this condition.

An arm with a bandaid on the upper arm.
The Australian government now recommends the Pfizer vaccine for adults under 50, rather than the AstraZeneca one.
Shutterstock

Understanding risk

It’s important to note every therapeutic agent (a drug or a vaccine, for example) carries the risk of unintended consequences. For most of us, most of the time, this will be minimal. This is a biological reality reflecting the interconnectedness and complexity of the human body.

So like for any other therapeutic agents, there are risks as well as benefits we have to accept in taking COVID vaccines. What we need to do is to weigh up these risks against the benefits.

We make these sorts of calculations every day in all aspects of our lives. When we decide to get in the car, we know there’s a risk associated with driving. But we assess the risks are worth taking as the benefits of getting where we want to go quickly are worth it.

Mostly, we make these calculations without being consciously aware we’re doing it. Sometimes the parameters underlying these calculations are easy to grapple with — but sometimes they’re more nebulous.




Read more:
Australia’s bungled COVID vaccine rollout suffers another setback. Here’s how we can get it back on track


Weighing up the risks and benefits of the AstraZeneca vaccine

We know the vaccine offers near-complete protection against severe disease and death from COVID-19.

We also know severe side effects from the vaccine, in particular vaccine induced prothrombotic immune thrombocytopenia (VIPIT, the blood-clotting disorder in question), are extremely rare. But the condition is serious and around 25% of people have died after developing VIPIT.

There are a range of estimates of how often this syndrome occurs. But it’s generally accepted its incidence is about 4-6 cases per million doses of vaccine.

To put it in perspective, this puts the risk in the same order of magnitude to the average risk of dying if you complete a marathon, go scuba diving, or rock climbing.

It’s also important to note that we’ve started to see a pattern in that those who are at higher risk of this syndrome tend to be younger and tend to be women. We don’t have a clear understanding of why this is, but recognising this is really helpful in terms of making decisions about how to mitigate this risk.

Why the balancing act isn’t so easy

Although we have a pretty good understanding of the rate of severe outcomes from COVID-19, since we have over 12 months’ experience now of this illness, context is important. There are different levels of risk depending on where you live and what the rate of transmission in the community is.

While it’s all well and good in some countries to say you’re more likely to get very sick with or die from COVID than experience a complication from the vaccine, in Australia we have next to no COVID, so the risk of adverse outcomes from COVID is much lower. This needs to be factored into the equation.

We also have different strains of the virus, which can vary in how infectious they are and how sick they might make you. This also needs to be added to the mix.

In acknowledging the difficulty in completing these risk-benefit analyses, it’s really helpful to use a visualisation the University of Cambridge has put together based on UK data, which we’ve adapted here, comparing the risks and benefits of the AstraZeneca vaccine.



It depicts the risk of adverse effects from COVID (being in ICU) against adverse outcomes from the vaccine, based on an assumed incidence of COVID in the community of two in 10,000 people. Although the incidence rate in Australia is lower than this, this visual is extremely useful in conveying the nature of the relationship between the risks and benefits of the AstraZeneca vaccine in Australia.

What this visual shows clearly is that the benefits of the vaccine increase the older you are, because the risk of severe disease is higher the older you get.

It also shows that although the risks of side effects from the vaccine are relatively small regardless of age, the gap between risks and benefits narrows the younger you are. This is in part due to the reduced benefit of the vaccine for younger people who are less likely to have severe symptoms from COVID, and in part due to the increased risk of serious side effects, such as blood clots, for younger adults.

This visual clearly communicates the rationale for the changes announced yesterday. Where the risk-benefit becomes marginal, it makes sense to use other vaccines for younger adults — the Pfizer vaccine and possibly the Novavax vaccine down the track. The recommendations are both cautious and sensible.




Read more:
What you need to know to understand risk estimates


The Conversation


Hassan Vally, Associate Professor, La Trobe University

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

Australian vaccine rollout needs all hands on deck after the latest AstraZeneca news, mass vaccination hubs included


from www.shutterstock.com

Mark Hanly, UNSW; C Raina MacIntyre, UNSW; Ian Caterson, University of Sydney; Louisa Jorm, UNSW; Oisin Fitzgerald, UNSW, and Timothy Churches, UNSWAustralia’s vaccine rollout is due to be reset after the news last night the AstraZeneca vaccine would not be recommended for people under 50. Instead, this age group will be offered the Pfizer vaccine, with the federal government today announcing it had secured an additional 20 million doses.

Although details of the redesigned rollout have yet to be released, our new modelling, which has yet to be published in a peer-reviewed journal, shows how this might work under a range of scenarios, including the logistical requirements of different vaccines, and different vaccination venues.

Once a steady stream of locally manufactured AstraZeneca vaccine is available in Australia, the bottleneck in the vaccine rollout will shift from supply to administration. That’s when expanded GP vaccination clinics and mass vaccination hubs will be needed to deliver these jabs to nine million people over 50 in phases 1b and 2a of the rollout.




Read more:
New setback for vaccine rollout, with AstraZeneca not advised for people under 50


Here’s what we did and what we found

We used mathematical simulations of waiting in line, known as stochastic queue network models, to model the process of running a vaccination clinic.

Queue models allow us to assess the daily vaccination capacity for different venues, taking into account available staff numbers and estimated times to complete each stage of the vaccination process.

The two key venues we looked at were mass vaccination hubs — which could be large venues such as halls, parks or stadiums — and GP clinics.

Mass vaccination hubs and GP clinics lay out their vaccine clinics differently. Hubs with larger premises and more staff can adopt an assembly line approach to vaccination. They can divide the tasks of registration, clinical assessment, vaccine preparation and administration across a series of stations. Smaller clinics are likely to have fewer people available, each performing multiple tasks. We developed two distinct models to reflect these different set-ups.




Read more:
Australia urgently needs mass COVID vaccination hubs. But we need more vaccines first


We used these models to estimate how many vaccines could be delivered in an eight-hour clinic based on a range of staffing levels, within an average overall waiting time of under an hour.

We estimate a small general practice could administer 100 doses, rising to 300 doses for a large practice. Mass vaccination clinics could deliver 500-1,400 doses in the same period, depending on staff numbers.

We also used our models to test how clinics would perform under service pressures, including increased vaccine availability and staff shortages.

For both delivery modes, sites with more staff were better able to keep waiting times under control as system pressures increased. Unsurprisingly, mass vaccination hubs were more robust compared to GP clinics.




Read more:
4 ways Australia’s COVID vaccine rollout has been bungled


We can test different scenarios

Our models rely on subjective assumptions about the time needed to complete different stages in the vaccination process. In reality, these timings will vary in different contexts.

For instance, the Pfizer vaccine takes longer to prepare than the AstraZeneca vaccine. Our models can account for this by increasing the expected preparation time and seeing how many extra staff would be needed to run a vaccine clinic with the same number of appointments. When the Novavax or other vaccines come on board, we can re-run the model with updated preparation times.

In fact, we have developed an an app that allows anyone to re-run our simulations based on their own assumptions about service times, appointment schedules and staffing availability.

Vaccination simulator
Anyone can use the app to plug in how vaccination might play out under different scenarios.
Author supplied/UNSW

This can support policymakers, individual GPs and community pharmacies to plan vaccination delivery, as the quantity and type of available vaccine varies throughout the rollout.

However, there are some aspects of vaccine rollout our models do not account for. This includes essential support staff, such as administrators, cleaners and marshals.

Neither do our models address the logistics of distributing vaccines to vaccination centres, which is a separate challenge.




Read more:
How the Pfizer COVID vaccine gets from the freezer into your arm


One isn’t ‘better’ than the other. We need both

Our models suggest mass vaccination hubs and GP clinics are equally efficient in terms of the number of doses delivered per staff member. This supports distribution through both modes, provided GPs are enabled to vaccinate at their peak capacity.

These two approaches offer distinct advantages. Older people or clinically vulnerable patients may benefit from attending their local GP, who will be familiar with their medical history.

Younger males, busy working people and marginalised populations are less likely to have a regular GP and may be easier to reach through mass vaccination hubs. The rollout of phase 2 to adults under 50 may require expansion of the hubs, as not all GPs may be able to store the Pfizer vaccine.

A diverse profile of vaccination sites, drawing on the benefits of different distribution modes, will help maximise the daily vaccination rate and vaccinate the Australian population against COVID-19 as quickly as possible.The Conversation

Mark Hanly, Research Fellow, UNSW; C Raina MacIntyre, Professor of Global Biosecurity, NHMRC Principal Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW; Ian Caterson, Medical Lead, Royal Prince Alfred Hospital COVID Vaccination Clinic, Sydney Local Health District, Boden Professor of Human Nutrition, School of Life and Environmental Sciences, University of Sydney; Louisa Jorm, Director, Centre for Big Data Research in Health, UNSW; Oisin Fitzgerald, PhD Candidate, UNSW, and Timothy Churches, Senior Research Fellow, South Western Sydney Clinical School, UNSW

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

New setback for vaccine rollout, with AstraZeneca not advised for people under 50


Michelle Grattan, University of CanberraThe vaccine rollout was thrown into fresh uncertainty on Thursday night after the government received medical advice against using the AstraZeneca vaccine for people under 50 because of the very small risk of blood clots.

Most immediately, this means those younger health and aged care workers who have not yet been vaccinated will be offered the Pfizer shot. This may involve delays.

These people are in the cohort currently being vaccinated, together with over 70s who are unaffected by the new advice, which went to the government on Thursday evening.

Scott Morrison said the later stages of the rollout will now urgently be re-examined and re-calibrated. He said it was “far too early” to say what impact it would have on the rollout’s timetable.

The government’s deadline for all eligible people who want a vaccine to receive at least one shot by the end of October is set to blow out.

Vaccine purchases will also be reviewed.

Morrison unveiled the advice from the Australian Technical Advisory Group on Immunisation at a hastily summoned press conference on Thursday night, also attended by Health Minister Greg Hunt, Chief Medical Officer Paul Kelly, and Health Department Secretary Brendan Murphy.

Morrison said he had received the advice “in the last 15 minutes”.

The government had urgently sought the advice following evidence overseas of a link between the AstraZeneca vaccine and blood clots, with some deaths resulting.

There has been one clot case in Australia, a man in his 40s.

Explaining that the Pfizer vaccine should be preferred over AstraZenica for those under 50s, ATAGI said, “This recommendation is based on the increasing risk of severe outcomes from COVID-19 in older adults (and hence a higher benefit from vaccination) and a potentially increased risk of thrombosis with thrombocytopenia following AstraZeneca vaccine in those under 50 years”.

But it said AstraZeneca can be used in adults under 50 “where the benefits clearly outweigh the risk for that individual and the person has made an informed decision based on an understanding of the risks and benefits.”

Under 50s who’ve already had one AstraZeneca dose without serious adverse effects can be given a second dose, the advice said.

ATAGI described the possible blood clot side effect as “rare but serious”.

Advice is being provided to GPs involved in the rollout.

This is the latest difficulty to hit the rollout. The government this week stressed the main problem was shortage of supply, with AstraZeneca doses from Europe being held back and CLS, which is manufacturing the vaccine locally, not gearing up to the one million weekly target as fast as expected.

As of Thursday, one million doses of one or other of the two vaccines had been administered in Australia. At present Australia only has the two vaccines available.

Morrison stressed that decisions were up to individuals and their doctors – this was advice only.

“There is not a prohibition on the use of the AstraZeneca vaccine for persons under 50. There is an expression of a preference.”

Kelly said a clot was very rare. “At the moment, it seems to be around four to six per million doses of vaccine. It’s only been found in the first dose of the AstraZeneca vaccine, usually within four to 10 days after that vaccine. But it is serious, and it can cause up to a 25% death rate when it occurs.”

In a late night statement AstraZeneca said it respected the government’s decision based on advice to recommend AstraZeneca’s vaccine be used in those over 50.

It noted that, “Overall, regulatory agencies have reaffirmed the vaccine offers a high-level of protection against all severities of COVID-19 and that these benefits continue to far outweigh the risks”.The Conversation

Michelle Grattan, Professorial Fellow, University of Canberra

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

What is thrombocytopenia, the rare blood condition possibly linked to the AstraZeneca vaccine?


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Anthony Zulli, Victoria University; Maja Husaric, Victoria University; Maximilian de Courten, Victoria University, and Vasso Apostolopoulos, Victoria UniversityThe federal government has asked Australia’s medical and vaccine regulators to urgently consider the European Medicines Agency’s finding of a possible link between the Oxford/AstraZeneca COVID vaccine and rare blood clots.

This follows reports over recent weeks of blood clots in a small number of people around the world who had received the AstraZeneca vaccine, including one man who was hospitalised in Melbourne.

Scientists have termed the condition “vaccine induced prothrombotic immune thrombocytopenia” (VIPIT). But what does this actually mean, how significant is the risk, and what are the implications for Australia’s vaccine rollout — which is currently relying predominantly on the AstraZeneca jab?

A paucity of platelets

As indicated by its name, VIPIT is a form of something called thrombocytopenia.

Thrombocytopenia is a condition whereby the numbers of thrombocytes (very small blood particles, or platelets) are markedly reduced. Platelets form clots to stop bleeding, so when you don’t have enough platelets in your blood, your body can’t form clots. This can lead to excessive bleeding.

The condition has a genetic component, but can also arise from more than 300 common medicines, including penicillin and certain pain killers. Quinine, which is added to tonic water for flavour, can also very rarely cause thrombocytopenia.

The symptoms of VIPIT can include severe headaches, abdominal pain, seizures and visual changes. These are similar to the symptoms of thrombocytopenia unrelated to the vaccine.

In rare cases of thrombocytopenia, clots can develop in the vessels draining blood from the brain. The European Medicines Agency said it had received reports of 169 cases of brain blood clots in people who had been vaccinated with the AstraZeneca shot.

In severe cases, thrombocytopenia can be fatal. There have been deaths from blood clots reportedly associated with the AstraZeneca vaccine, including 19 in the United Kingdom.




Read more:
What can go wrong in the blood? A brief overview of bleeding, clotting and cancer


VIPIT appears to present 4-20 days after vaccination, and so far, the issue has been largely associated with women under the age of 65.

So how could this vaccine potentially cause thrombocytopenia? The “prothrombotic immune” part of the name denotes it’s caused by an over-activation of the immune system, which gives us a clue.

Platelets and COVID-19

The AstraZeneca vaccine prompts cells to make a specific part of SARS-CoV-2 (the virus that causes COVID-19), called the spike protein, which the virus uses to attach to cells when infecting us.

The vaccine stimulates our immune system to generate antibodies against the spike protein, which then primes the body to mount an immune response against SARS-CoV-2, if it encounters the virus in the future.

But in some people, the AstraZeneca vaccine seems to produce antibodies that react with platelets, making them stick together, leading the blood to clot. This in turn reduces circulating platelet numbers, and hence the thrombocytopenia.

These antibodies are similar to those found in some people on a blood thinning drug called heparin. The immune response to heparin generates antibodies that bind to platelets. This can lead to blood clots in some people, called heparin induced thrombocytopenia. As many as one in 20 patients receiving heparin develop thrombocytopenia.

Keeping in mind we’re yet to establish cause and effect, it’s a possibility that the biological mechanism by which we believe heparin leads to thrombocytopenia could be the same biological mechanism by which the AstraZeneca vaccine might.

How common is it?

Naturally occurring thrombocytopenia affects about one in 30,000 adults a year in the United States.

As for the suspected vaccine-induced kind, according to data collated by the Thrombosis and Haemostasis Society of Australia and New Zealand, VIPIT is as rare as one in 500,000 people. But the society notes the data are incomplete.

Different countries have reported different rates. Norway, for example, has so far reported one in 25,000 vaccinated adults under the age of 65 have experienced low platelet counts, bleeding, and widespread thromboses (blood clots).

Of course, the possibility that some of these cases of thrombocytopenia may have occurred regardless of the vaccine makes understanding vaccine-induced cases more complicated. But taken together, thrombocytopenia appears to be more common in the general population than among those who have been vaccinated.

As we continue to vaccinate the world, it’s likely small subsets of people will continue to experience this complication. Whether we can establish a causal link between the AstraZeneca vaccine and thrombocytopenia is subject to continued investigation.




Read more:
Politics with Michelle Grattan: Stephen Duckett on what’s gone wrong with the rollout


Be aware, but not alarmed

Amid this ongoing investigation, some countries, such as Norway, have paused their rollouts of the AstraZeneca vaccine. Others have restricted use of the vaccine in certain groups, like Canada, which is using it only for adults older than 55, who may have higher risks from COVID and lower risk of blood clots. Meanwhile, the UK has pledged to make other vaccine options available for younger people.

We will wait to see how the Australian experts respond. But for the general adult population, we agree with the current guidance from bodies including the European Medicines Agency and the World Health Organization that the benefits of the AstraZeneca vaccine outweigh the risks.

That said, it’s not unreasonable to be cautious. You should monitor for these symptoms up to 28 days after receiving the jab:

  • breathlessness
  • pain in the chest or stomach
  • swelling or coldness in the leg
  • severe or worsening headache
  • blurred vision
  • persistent bleeding
  • multiple small bruises, reddish or purplish spots, or blood blisters under the skin.

If you’re experiencing any of these symptoms and you’re concerned, seek medical advice.




Read more:
Data suggest no increased risk of blood clots from the AstraZeneca vaccine. Australia shouldn’t pause its rollout


The Conversation


Anthony Zulli, Associate professor, Victoria University; Maja Husaric, Senior Lecturer; MD, Victoria University; Maximilian de Courten, Professor in Global Public Health and Director of the Mitchell Institute, Victoria University, and Vasso Apostolopoulos, Professor of Immunology and Associate Provost, Research Partnerships, Victoria University

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

AstraZeneca’s blood clot risk is incredibly small. Australia shouldn’t follow the UK’s lead of offering under 30s another vaccine


Nathan Bartlett, University of NewcastleAuthorities in the United Kingdom overnight recommended people under 30 be offered an alternative COVID vaccine to the AstraZeneca/Oxford shot.

The recommendation came after the European Medicines Agency (EMA) found a “possible link” between the vaccine and blood clots. The EMA also said blood clots should be listed as a “very rare” side effect of the vaccine.

It’s important to note there’s still no conclusive evidence the vaccine is causing the clots, as so few have been reported. However, evidence there is a link is increasing, which has prompted more focused monitoring.

The benefits of getting a COVID vaccine still far outweigh the risks. I would still be encouraging everyone to be vaccinated with the AstraZeneca vaccine.

Prime Minister Scott Morrison said this morning “there’s nothing to suggest at this stage that there would be any change” to Australia’s current rollout strategy. The Therapeutic Goods Administration and the Australian Technical Advisory Group on Immunisation are currently reviewing the data and latest advice from Europe and the UK.

What’s causing these clots?

Blood clotting events linked to vaccination are being called “vaccine-induced prothrombotic immune thrombocytopenia” (VIPIT).

In these rare instances, clots are forming in a patient’s blood, and not just in veins but in arteries and other rare locations like the brain and abdomen. This is also paired with low platelet counts (cells needed for the blood to clot).




Read more:
What is thrombocytopenia, the rare blood condition possibly linked to the AstraZeneca vaccine?


It appears, in these instances, the body’s response to the vaccine is triggering an “off target” immune response that is attacking platelets. Limited data that is yet to be peer reviewed suggests antibodies targeting platelets cause them to become activated and trigger clotting. This autoimmune response also targets the platelets for destruction, reducing their level in the blood. So platelets are either tied up in clots or are eliminated. Both processes contribute to “thrombocytopenia” (low blood platelet count).

Like infections, vaccines trigger an immune response, so when receiving any shot that stimulates a robust immune response there’s a small but real risk your immune system will generate “off target” effects. In these rare instances, these effects can lead to autoimmunity, which is an immune response that attacks your own cells.

All vaccines and medications come with small risks

The numbers of clots reported after the AstraZeneca are very small, so we don’t exactly know how common they are. But they appear to occur at a rate between one in 25,000 and one in 500,000.

The UK’s vaccine advisory board said there were 79 cases of blood clotting issues among more than 20 million people given the AstraZeneca vaccine. That’s a chance of about 0.0004%, or one in 250,000.

Researchers haven’t yet identified any specific risk factors so far for the development of blood clots following COVID vaccination. We need to understand as quickly as possible what these are if indeed a causal link is established.

Some have suggested there could be a link with women taking the contraceptive pill having a higher risk of blood clots after receiving the AstraZeneca vaccine. But there’s no evidence for this at all. As far as I know, information on whether women receiving the vaccine are taking the contraceptive pill isn’t captured. Perhaps it’s something to consider going forward.

Young people don’t appear to be at particularly higher risk of blood clots linked to the vaccine. The publicised cases of blood clots have occurred in mostly women under 60 years of age.

Australia shouldn’t follow the UK’s new recommendation

One reason the UK is able to advise younger people to receive other vaccines is because it has other vaccine options, including the Pfizer and Moderna shots. Offering the under 30s an alternative vaccine isn’t really going to hinder the rollout, which is going very well in the UK.

But this isn’t the case in Australia. The AstraZeneca shot is the only one we have guaranteed supply of, given CSL is producing it in Melbourne.

It’s important to remember the AstraZeneca vaccine is a very safe and effective vaccine. It’s also easier to store and distribute than the Pfizer vaccine.

The priority is vaccinating as many people as possible and quickly

It’s important to note we’re in uncharted territory. This is the first time in modern history we’ve been in a situation where we’ve needed to roll out a vaccine to deal with a pandemic.

We’re also using new vaccine technologies that we’ve had to expedite to try and get on top of this virus as soon as possible. These new technologies, including AstraZeneca’s, have never been tested at this immense scale until now.

There are a lot of unknowns, but certainly the scale in which were doing this means we’re going to see very rare adverse events linked to these vaccines.

At this stage the priority is still to vaccinate as many people as possible, as quickly as possible.

My primary concern is ongoing high levels of transmission across the world. The more cases there are, and longer we delay vaccinating people, the higher the likelihood is of new variants of the virus emerging.




Read more:
UK, South African, Brazilian: a virologist explains each COVID variant and what they mean for the pandemic


Even though we have very low COVID-19 case numbers in Australia currently, we’ve seen regular outbreaks stemming from hotel quarantine. We can’t predict what’s going to happen in the future. The longer the virus is waiting at our doorstep, the greater the risk we’ll have another outbreak and end up in lockdown and much worse — and nobody wants that.The Conversation

Nathan Bartlett, Associate Professor, School of Biomedical Sciences and Pharmacy, University of Newcastle

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