Anna Riddell answers questions about the COVID-19 vaccines
To say the COVID-19 virus has had a dramatic impact on lives across the world is an understatement. As a result, for many people 2020, the year in which ‘hands, face, space’ became an unlikely mantra, is a year to be forgotten.
But in a welcome plot twist to this almost movie-like year, a COVID-19 vaccine has been approved for use in the UK. The approval of a vaccine, which is likely to be the first of many to protect us against this awful virus, is fantastic news.
Nevertheless, this approval has understandably raised a lot of questions about vaccines – both broadly and relating to COVID-19.
Here, Dr Anna Riddell, a Consultant Virologist at Barts Health NHS Trust, answers some common questions about COVID-19 vaccines to provide people with accurate information so people can make an informed choice regarding vaccination.
How were these vaccines created so fast?
“It’s true the COVID-19 vaccine is new in the same way the COVID-19 virus is new. But the vaccine technology used to develop vaccines against the virus isn’t new.
“Scientists around the world have been working on these so-called ‘mRNA vaccines’ for decades, in relation to other infectious diseases like influenza and rabies. In addition to this, we already knew a lot about other types of coronaviruses, the family of viruses COVID-19 is in before this new disease came along. So we were able to use this prior knowledge and apply it to COVID-19.
“All of this means that when COVID-19 was first identified in December 2019 and the race to develop a vaccine began, we weren’t starting from scratch – we had a head start.
“As well as this, the COVID-19 vaccines have been developed under extraordinary circumstance. Under usual circumstances, the development of vaccines – from the trials that test them to the processes that approve them – can take many years, due to administrative and bureaucratic processes.
“However, in the case of COVID-19 vaccines, these trials and processes were tweaked and improved, and run in parallel with one another, as opposed to in separate stages, speeding the process up. This was motivated by the devastating health and economic costs caused by the global pandemic and the urgent need to find a vaccine.
“And it was able to happen because of the fantastic collaboration that went on between researchers and regulatory organisations. The collaborations allowed vaccine clinical trials to be conducted at speed – but without missing necessary steps to ensure safety – and any successful vaccines to be approved quickly.
“No clinical trial can take place if there aren’t volunteers. In the case of COVID-19 vaccine clinical trials, which were developed during a pandemic, thousands of volunteers were recruited to trials very quickly. Under ‘normal’ circumstances, it’s likely that this would have taken a lot longer, because people would have been unable – or unwilling – to participate for a variety of reasons including work commitments etc.
“The high rate of COVID-19 infections also helped deliver these trials quickly. Because the rate of COVID-19 infection was very high while these trials took place, it meant the effect of the vaccines could also be assessed very quickly.
“This also means researchers could see if the vaccine worked or not almost immediately, rather than have to wait for the right season, like the case of testing new flu vaccines”.
These vaccines were created very quickly – are they safe to use?
“It’s natural that people may be nervous and sceptical about the safety of a vaccine that has been developed so quickly.
But rest assured that like every other vaccine before them, vaccines against COVID-19 have been thoroughly tested to make sure they are safe.
“Safety is paramount to all involved and the independent regulator (the MHRA) would not approve any vaccine that has not been tested and found to be safe.”
How can we be sure that the vaccine works if it’s not been tested for very long?
“Like any new vaccine being developed, vaccines against COVID-19 have to be tested in phase 3 clinical trials to make sure they’re safe and that they work. These trials involve thousands of people because we want to make sure any results that show the vaccine work are real and are not due to chance.
“In the case of the Pfizer Biontech COVID-19 vaccine, over 18,000 people were given the vaccine in the phase 3 trial. The results from the trial, which was carried out in Brazil, the USA, Germany and Argentina showed the vaccine was 95% effective, which is an amazing result.
“The results also showed that were 8 cases of COVID-19 in group of people who received the vaccine, compared to 162 cases of COVID-19 in the group of people who got a ‘dummy’ (placebo) vaccine. There were no cases of severe COVID-19 in the vaccine group.
“These results mean we can be very sure that the Pfizer Biontech COVID-19 vaccine works. The UK was the first country to approve this vaccine for use and it has now been approved in the USA, Canada and EU member states for use.”
“The results of the trials for the Oxford AZ vaccine were equally impressive. The trial, which included over 11,000 people, reported the vaccine as being 70.4% effective against COVID-19 overall.
“There were no cases of severe COVID-19 among those who got the vaccine, and two in the control group (i.e. those who didn’t get the vaccine), which suggests the vaccine offers protection against severe disease.
This Pfizer / BioNTech COVID-19 vaccine is an ‘mRNA vaccine’ – what does this mean?
“There’s been a lot of talk about the Pfizer Biontech COVID-19 vaccine (and indeed, some others on the horizon) being an mRNA vaccine. This means that these vaccines contain something called messenger RNA (mRNA). The mRNA is a genetic code that our cells use to make a bit of the COVID-19 virus (the ‘spike protein’) which in turn, causes our immune system to kick into gear and produce antibodies and other anti-virus immune responses.
“What this also means is that these types of vaccines do not contain live virus and so are unable to cause disease. This is a huge advantage to them.
“Another big advantage to mRNA vaccines is that compared to other types of vaccines, they can be developed in laboratories and their production can be easily scaled-up. This makes vaccine development in the face of a new disease like COVID-19 much quicker and easier.”
This Oxford / AstraZeneca COVID-19 vaccine is an ‘adenovirus vaccine’ – what does this mean?
“The Oxford / AstraZeneca COVID-19 vaccine uses a slightly different of technology to mRNA vaccines like the Pfizer BioNTech vaccine.
“In the case of the Oxford / AstraZeneca COVID-19 vaccine, a modified, virus similar to the common cold –a type of adenovirus – is used, which includes the genetic code for the COVID-19 spike protein.
“The adenovirus delivers this genetic code to our cells which then produce the spike protein. This then acts as a signal to the immune system to mount an immune response, including the production of antibodies.
“Like mRNA vaccines, adenovirus vaccines mimic what happens during a natural infection, but they can’t cause a person to develop COVID-19 as they don’t contain live COVID-19 virus.
“And we also have decades of experience with ‘adenovirus vector technology’ including vaccines against infectious diseases and in cancer therapy.”
Can vaccines enter our DNA and change it?
“Put simply, no, these vaccines cannot and do not enter our DNA and they can’t change it. In fact, this is physically impossible!
“Vaccines act only as messengers. They alert our immune system, telling it there’s something in our body that shouldn’t be there. In the case of COVID-19 vaccines, that ‘something’ is a very small piece of the virus, the spike protein, which prompts our immune system to mount a response against it. This response is remembered by our immune system, meaning it is then ready to fight and kill off COVID-19 if encountered in the future.”
What about side-effects?
“Like every other vaccine in the world – and indeed like every medicine and treatment – COVID19 vaccines may cause side effects in some people who are vaccinated.
“This does not mean that every person who has a vaccine will experience side effects, or that the side effects will be particularly bad or damaging.
“It’s also important to remember that no vaccine will be approved – or even be tested in a phase 3 clinical trial – if it hasn’t first passed other safety checks. At every stage of a vaccine’s development, from animals studies right through to phase 1 and phase 2 trials, safety is always being checked and side effects monitored.
“In the case of the Pfizer Biontech COVID-19 vaccine, no significant harm or side effects were identified at any stage of development. Some people who get the vaccine may experience mild side effects like a sore arm or a headache, but most of the side effects reported for the Pfizer Biontech COVID-19 vaccine have been mild or moderate, and disappear within a few days.
“In the case of the Oxford / AstraZeneca COVID-19 vaccine, mild pain and tenderness at the injection site were common side effects in all age groups. These so-called ‘local side effects’, as well as other side effects like fever, headache, muscle ache and joint aches occurred in 10% of those who got the vaccine in the trial.
The risk of dying from COVID-19 is minimal, why would I bother getting a vaccine?
“It’s true that the overall risk of death from COVID-19 is low (approximately 1%).
“However, the risk is much higher in elderly people, some ethnic minority groups and people with pre-existing illnesses. In fact, there have already been around 67,000 deaths from COVID-19 in the UK. So while the risk of dying may be ‘minimal’ for some people, we have to think of those around us as well.
“We also can’t forget that a large number of people who have had COVID-19 suffer from long-term after-effects, such as extreme tiredness, difficulty breathing, a persistent cough, heart problems, and problems with the nervous system which may cause long-term illness or disability. This is ‘post COVID-19 syndrome or long COVID’ and can affect people of all ages.
“So for all these reasons, getting a vaccine is a good idea if you are able to as it is the best way to protect you and those around you.”
When can I get a COVID-19 vaccine if I want one?
“Right now, COVID-19 vaccines are being delivered to people who are aged 80 or over, care home residents and staff and high-risk NHS staff, in accordance with guidance from the Joint Committee on Vaccination and Immunisation.
“If you do wish to have a vaccine, please don’t contact the NHS to seek one – they will contact you. When they do contact you, please attend your booked appointment and in the meantime (and even after being vaccinated), please continue to follow all the guidance to control the virus and save lives, including ‘hands, face, space’”.