The COVID-19 vaccines have been developed at break-neck speed and in some cases use new technology.
It’s little wonder some of you have questions.
Since August last year, we’ve been collecting your queries and concerns about the coronavirus and COVID vaccines.
With the Pfizer shot rolling out in Australia this week, we’ve put the questions you asked most to leading experts in infectious diseases and immunisation.
From why you need a vaccine if you have a strong immune system to whether genetic vaccines can change your genome, we’ve got the answers.
Meet the experts
Kristine Macartney is an infectious diseases paediatrician and University of Sydney professor. She monitors the safety and effectiveness of vaccines as director of the National Centre for Immunisation Research and Surveillance (NCIRS).
Christopher Blyth is an associate professor in paediatrics at the University of Western Australia and co-director of the Wesfarmers Centre of Vaccines and Infectious Diseases. He is co-chair of Australia’s peak scientific committee on immunisation, a research fellow at Telethon Kids Institute, Infectious Diseases Physician at Perth Children’s Hospital and a clinical microbiologist at PathWest Laboratory Medicine.
Archa Fox is an associate professor and ARC Future Fellow at the University of Western Australia. She is a molecular biologist specialising in RNA, the genetic code behind viruses and many of the COVID-19 vaccines.
Why do I need a vaccine?
Isn’t it better to risk COVID than take a new vaccine?
Professor Macartney: Though they are new, these vaccines have been so incredibly well studied. There’s now more than 200 million doses that have been administered globally and tens of thousands of those were in clinical trials. So we actually know more about these vaccines than we have about some other vaccines launched in years past. It’s amazing what we’ve been able to learn because of the mass participation of people in these trials and roll-out.
Can’t I wait and see while others take it?
Professor Macartney: While a young person has a reasonable chance of not becoming critically ill with COVID-19, they certainly have a chance of passing it to others who are vulnerable and it could have serious health consequences.
The key thing here is that we will only succeed in stopping this pandemic if most of the population is vaccinated. And while some people may think “I don’t need to be vaccinated, I’ll rely on others”, we know that if everyone joins together, taking up the safe and effective vaccines we have, that’s how we can turn this into being a manageable virus rather than one wreaking havoc on our world.
We’ve been hoping life will be normal by 2022 — it’s not quite as black and white as that. If we wish to get back to a more normal life, we quite simply need to get a lot of people protected against serious disease through vaccination.
Why can’t we just immunise the vulnerable and leave others to fight COVID with their immune systems?
Professor Macartney: If we do that, this virus will continue to spread, especially to those with weaker immune systems or who are vulnerable. These people, even if they are vaccinated, will not be fully protected. They also need to rely on not meeting another person who is infected with the virus. Some people’s own immune response may not respond as well to the vaccine, or if they met someone who had a very high level of virus it may overwhelm their protective response from the vaccine. The key thing here is to not meet anyone with the virus, and the way to do that is through mass vaccination, so the virus will not have anywhere to travel.
If we have a lot of people who aren’t vaccinated, the virus will just continue to spread and be a risk to our families and friends. We cannot afford to have it circulating at high levels in the community.
It sometimes seems okay to say “I don’t mind if I get sick”, but in my experience as a clinician who looks after people in intensive care, when others feel they might have passed on that infection to a person who ends up seriously ill in hospital, it’s a terrible burden to bear. People feel absolutely devastated about that — knowing they didn’t do everything they could have.
Everyone knows or cares for someone who is older, or might have had treatment for cancer, or for some other reason will be vulnerable. It’s so important that we think of those people, because if we’re not vaccinated, we’re keeping them at risk.
Dr Fox: Younger people can strengthen their immune system but as you get older your immune system is just not as good. It’s just part of getting older. The only way we can protect older people and the immunocompromised is to vaccinate.
But even if every young person ate well and did exercise and had a strong immune system, if they get infected with the virus, they could still suffer from COVID-19 — some people develop long COVID, and there is mortality in all age ranges, even if you have a strong immune system. We don’t yet understand why some people get really bad COVID-19 symptoms and others don’t. In future we may know people’s risk factors at the genetic level, but right now you’re playing Russian roulette if you’re going to just rely on boosting your immune system to stop getting sick.
If everybody just takes an individual stance and boosts their own immune system, that’s not how vaccines work — they rely on herd immunity, it’s about you protecting everyone else. The studies coming out now suggest transmission of the virus will be greatly reduced by the vaccinated.
Dr Blyth: Although we encourage people to stay healthy, there is no single way to strengthen one’s immune system to make it able to combat COVID infection. The only way we’re going to be able to do that is through a vaccine. So I’d encourage people to remain as healthy as possible throughout the pandemic but a key component is a vaccination. While we know some groups in particular are more susceptible to severe outcomes, COVID can affect anyone.
Is it safe?
Have approvals and testing been rushed through?
Professor Macartney: I understand people’s concern given that everything has happened at pandemic speed. But it’s important to remember that this has been the focus for hundreds of thousands of the world’s cleverest scientists, those in regulatory authorities, and specialists in ethics and many aspects of the vaccine development and delivery process. They’ve all been working round the clock to ensure the integrity and quality of the data and the vaccines themselves. The whole scientific world and many others have turned their minds to ensuring that the quality and safety of the vaccines is paramount. Billions of dollars have been thrown at this to back that approach.
While things have gone much faster than usual, the rigour with which testing, approvals and all aspects of development have been undertaken has been of the highest standard. So many people have stopped doing the other work they do to become involved in COVID — they’ve turned all of their skills to support the development and manufacture. That’s what’s helping us know they’re safe and quality products.
Dr Fox: These vaccines have not been rushed through. They are faster because there have been absolutely no delays to getting funding. As scientists, we spend so much time trying to get funding for the necessary trials and experiments to prove something works. That is the biggest delay to scientific research. Then, at every stage there were people lining up to participate in trials. Often that recruitment is difficult and a very long process. It’s really those two things that removed the usual waiting times. That’s why what would previously take five years took one year.
In Australia, our vaccines have had the full approval process, not emergency authorisation like in some countries. That means every bit of data that was required for approval has been provided, whereas with emergency approval they don’t require quite so much data. The regulators who sit on those approval panels would’ve been working around the clock to scrutinise that data. In that sense there would’ve been a bureaucratic layer stripped away as they were able to focus on this approval, not other work.
Dr Blyth: Current technology enables us to develop vaccines much faster than previously and through collaboration between researchers and industry we’ve been able to do this in record time.
In addition to new technology, we did things differently this time, running trials concurrently. Traditionally, we run the three phases of clinical trials one after the other, pausing to review data between steps. But we were able to run them continuously in populations with large amounts of COVID disease, so it was faster to see if a vaccine truly worked. This was an economic risk for manufacturers and governments but not a safety risk.
The threshold for approval for these vaccines in Australia has been no different for COVID than any other vaccine. They’re going through as rigorous, if not more rigorous a process than usual, given the incredible scrutiny. I have confidence they are safe and effective.
How do we know there won’t be longer-term effects if we’re testing short term?
Professor Macartney: It’s extraordinarily rare for any vaccine to show a side effect that develops later after vaccination, such as the following week. Most side effects occur within the first few days, such as a sore arm, muscle aches or a temperature. Very few vaccines have ever been shown to have a late-onset side effect. But the regulatory authorities who’ve approved the vaccines have only done so on the basis of reviewing data from many thousands of people at least two months after the second dose of the vaccine. Those people are continuing to be followed.
Vaccines have been in clinical trials for nine months now where they’ve been given to over a quarter of a million people in those trials. More than 200 million doses of approved vaccines have also now been given worldwide and many doses have been of the two vaccines we’re using in Australia. So far, we’re not seeing longer-term side effects. But that doesn’t stop us from continuing to monitor the safety of the vaccines. Studies are being done all around the world looking for those needle-in-a-haystack events — but we know the benefits of these vaccines are so great and the safety profile is looking excellent.
Dr Fox: The only way we can be 100 per cent sure there are no long-term problems is to monitor long-term. But when you add up all of the bits of evidence that have been gathered — studies in animals over long periods of time that show they’re fine, and the ways we know the molecules and cells work, that they’re broken down quickly — there’s no scientific basis to believe there’ll be long-term effects.
As a scientist these vaccines don’t scare me at all, because I can look at all the components and know they’ll either degrade or are harmless.
Every vaccine was new once. Most of us don’t think too much about getting the whooping cough vaccine or diphtheria vaccine — at some point they were the new ones, but our parents or grandparents agreed to take them.
Genetic vaccines
The two vaccines currently approved in Australia (the Pfizer-BioNTech and Oxford-Astrazeneca shots) are what’s known as “genetic vaccines”. Traditional vaccines inject a weak or inactivated copy of a virus, or a lone protein from it, to train your immune system to recognise and destroy that virus. Genetic vaccines instead give your cells instructions to make a single protein from the coronavirus themselves. As it is a single protein not a whole coronavirus particle, you can’t get sick.