Let us know you've had your vaccines elsewhere

Please let us know if you've had your flu jab or your Covid-19/booster jab elsewhere using the form below. You can also use our forms below to decline a flu or Covid-19/booster vaccine.

Giving us this information helps keep our records up to date so we can get an accurate indication of how many colleagues have extra protection against flu and Covid-19. 


Vaccine FAQs

Dr Anna Riddell, consultant virologist, goes on a myth-busting mission to provide people with accurate information so you can make an informed choice regarding vaccination. 

  1. Changes for this year
  2. Vaccine development
  3. Vaccine safety
  4. What is an mRNA vaccine?
  5. What is an adenovirus vaccine?
  6. Vaccines and our DNA
  7. What are the side effects?
  8. Why should I get a vaccine?

Vaccinating Barts Health, answers from our vaccine programme team

  1. How does the vaccine work?
  2. Vaccine and infection control
  3. I'm concerned about the vaccine

Changes for this year

What vaccine is it for this year? 

For the autumn 2022 COVID vaccine booster, mRNA vaccines (from Pfizer or Moderna) will be offered. There will be two different types of vaccines. The availability of each type will depend on supply. The two types of vaccines will be: 

  • A ‘monovalent’ vaccine containing mRNA encoding the spike protein from the original wild type COVID virus.  

  • A newer ‘bivalent’ vaccine containing mRNA encoding the spike protein from both the original wild-type COVID virus as well as the newer Omicron variant. 

Does it fight against more than one strain? 

The new bivalent vaccines use the same technology as the mRNA vaccines we are already familiar with but contain the code for the spike protein from the original COVID virus as well as the newer omicron variant. Although improved antibody responses against the omicron variant were observed in studies of these newer vaccines, it is not certain how much advantage this will provide in the real world due to the evolution of the omicron variant. What is known is that both types of vaccines offer good protection against severe disease i.e. hospitalisation and death. 

I have had 3 booster vaccines, am I okay to have a 4th? 

There are no safety concerns regarding having a 4th dose of a COVID vaccine. Booster doses are required to maintain adequate protection against severe disease for the omicron COVID variant as well as new variants that may evolve over the Winter season if the prevalence of COVID increases again. 

Will I have the Covid-19 booster and the flu vaccine at the same time? 

It is safe to have both vaccines at the same time. Neither the COVID booster vaccine or the flu vaccine are live virus vaccines and therefore there is no interaction between the two vaccines.  

Can I have different types of Covid-19 boosters? I previously had Pfizer 

There are no significant safety concerns regarding having different types of COVID-19 vaccines/booster doses. The mRNA vaccines all work in the same way and there is no disadvantage/advantage to having Pfizer followed by a Moderna vaccine or vice versa. Even if you have received the AZ vaccine previously, there are no risks to having an mRNA vaccine for your booster (and potentially some immunological benefit). Side effects following booster vaccines are similar to those seen after the primary course i.e. local injection site pain, tiredness, headache and muscle aches. Side effects following Moderna vaccine booster in someone who has previously received either the Pfizer or AZ vaccine are more common.  


Vaccine development

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”. 

Will the booster protect me against the Omicron variant? 

The amount of protection a vaccine provides against any infection is dependent on the infection and the type of vaccine.

It is rare for vaccines against respiratory viruses to protect against infection. In most cases, we are looking for protection against serious disease (i.e. hospitalisation) or death.

Information from the UK health security agency which combines national data on vaccination, GP health records and other large cohorts estimates a vaccine effectiveness  (VE, real word) against symptomatic disease from omicron of 45 to 50% following two doses of AZ vaccine and 65 to 60% following an mRNA vaccine. Both VEs drop significantly 25 weeks after the second dose. A booster dose following either scenario then improves effectiveness to up to 60% against symptomatic disease.

Protection against symptomatic disease is not the whole story here. Protection against hospitalisation with omicron is also significantly improved following a booster. VE against hospitalisation after an mRNA booster is around 90% initially which then falls to around 75% 2 to 3 months later.

Vaccine safety

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 eight 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.  

Watch healthcare professionals across the NHS explain how the vaccine is given and give clear evidence that the vaccines work and are safe

Can vaccines affect fertility?

The Royal College of Midwives and The Royal College of Obstetricians and Gynaecologists have issued a joint statement: “We want to reassure women that there is no evidence to suggest that Covid-19 vaccines will affect fertility. Claims of any effect of Covid-19 vaccination on fertility are speculative and not supported by any data. There is no biologically plausible mechanism by which current vaccines would cause any impact on women's fertility. Evidence has not been presented that women who have been vaccinated have gone on to have fertility problems.”

The vaccine is also safe and recommended for pregnant women. Read more about taking the vaccine while pregnant and breastfeeding

The 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.  

The 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 virus – 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 – Covid-19 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-19’ 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.

How does the vaccine work?

When am I immune?  

No vaccine provides 100% protection against infection or total immunity to a disease. That’s why you should continue to follow the guidance of ‘hands, face, space’ even after you have been vaccinated. A good degree of protection to Covid-19 is afforded at around four weeks after the first dose of either of the two vaccines currently available in the UK. 

Will herd immunity protect me if everyone else is vaccinated?

The number of people that need to be vaccinated in the population to provide enough herd immunity to protect against Covid-19 is so high that is it unlikely to be achieved before the end of 2021. You are much better protected against Covid-19 by vaccination than herd immunity. 

I look after elderly relatives.  Will the risk of transmission be reduced?

We do not know yet if or how well the vaccines reduce the transmission of Covid-19. Your elderly relatives should also be offered the vaccine which will help to prevent them developing Covid-19. 

Vaccine and infection control

Do I still need to do my lateral flow (LFD) testing?

Yes. You should not change our behaviour because you have been vaccinated. Protection afforded by the vaccine is not 100%. If you have a positive LFD result after receiving the vaccine it is likely to indicate you have Covid-19 and is unlikely to be linked to the vaccine. So far we know that the vaccines protect against disease, but we don’t know if they also protect against infection. This means that you could still be infected, even if you don’t have symptoms and so are able to transmit the virus to others, despite being vaccinated.

Can I now reduce my mask wearing?

No. Infection control measures should not change because you have been vaccinated. You should continue to socially distance, wear appropriate PPE and wash your hands for at least 20 seconds.

Are vaccines better at preventing Covid-19 than infection prevention control measures?

There is no head to head comparison comparing vaccines and infection control measures as way to prevent infection by Covid-19. We are in unprecedented times and should use all available tools to bring the virus under control and protect our NHS and our families. Vaccines and infection control measures are so far the best tools we have and we should use both. This means that even after you receive your vaccine, you should still follow the guidance of ‘hands, face, space’.

I'm concerned about the vaccine

I’ve noticed some people feeling ill after the vaccine who previously had Covid-19. Does that mean they are already immune?

Fever, arm soreness and mild flu like symptoms are common soon after either vaccine. This does suggest your immune system is responding to the vaccine. These symptoms are common with other vaccines that are widely used. This is not the same thing as being immune.

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