Understanding more about the Covid-19 Vaccine

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With the roll-out of the COVID-19 vaccines nationwide, there finally seems to be a light at the end of the tunnel.

Understandably some people still have concerns as to the safety and effectiveness of the vaccine. We wanted to help you understand more about the Covid-19 vaccine.

What are the Covid-19 vaccines?

There are currently three COVID-19 vaccines approved for use in the UK: two mRNA-based vaccines from Pfizer/BioNTech and Moderna, and a virus-based vaccine from AstraZeneca and Oxford University (both of these are being currently rolled out), with other vaccines now looking to get regulatory approval. Vaccines work by preparing our immune system to recognize a virus or bacteria that can cause disease.  This is achieved by introducing a harmless version into our bodies so that our immune cells can learn what they look like and are prepared to respond to the virus if exposed to it in the future.

Are the Covid-19 vaccinations safe?

All Coronavirus vaccines that are approved must go through all the same clinical trials and safety checks that all other licensed medicines undergo.

With unprecedented worldwide collaboration, planning and investment, the vaccine was able to be developed in a much shorter time frame than has ever been seen. Some people are sceptical about the vaccine because of the speed in which it was developed but there are many reasons why the Covid-19 vaccine could be developed so quickly:

  • The Pfizer/BioNTech and Moderna vaccines were created with a method that has been in development for almost two decades, so the companies could start the development process early in the pandemic.
  • China isolated and shared genetic information about Covid-19 promptly, so scientists could start working quickly.
  • Vaccine projects had plenty of resource from governments.
  • Social media helped engage volunteers quickly with the research companies.
  • Some companies began making vaccines early in the process – before regulatory approval – so supplies were ready when authorization occurred.


For further information on specific concerns, these links may be useful:

The COVID-19 vaccines can have side effects, but the vast majority are very short term and not serious or dangerous. The vaccine developers report that some people experience pain where they were injected; body aches; headaches or fever lasting a few days. These are signs that the vaccine is working to stimulate your immune system. In research recently the Zoe app team conducted a survey of over 40,000 people who had had the first Pfizer vaccine. 37% experienced local after-effects around the site of the injection rising to 45% after the second vaccine. 14% had a ‘whole body after-effect’ such as a fever or chill within 7 days of the first dose and rising to 22% after the second dose. These effects got better after a few days.  If you have allergies, especially severe ones that require you to carry an EpiPen,  you should talk to your doctor.

How effective is the vaccine?

Importantly no vaccine can offer 100% immunity,  as we are all unique and our immune systems will respond slightly differently to any vaccine. The Pfizer vaccine has 95% efficacy which means that vaccinated people have 95% less chance of infection compared to those unvaccinated. The Oxford/AstraZeneca vaccine has 62 – 90% efficacy; although lower this is still considered highly protective. These levels of protection are only achieved after two doses of the vaccines. This can be compared to the annual flu jab which has typically between 40-60% efficacy.

In terms of ‘transmissibility’, a recent trial by Oxford AstraZeneca has indicated that it has a substantial impact on transmission by reducing the number of infected individuals in the population.

When will I get the vaccine and which one will I get?

To get a Covid-19 vaccination in England you must be registered with a local GP surgery.

The time when you receive the vaccine will be determined by your age, health, and profession; initial groups include people within the health and care professions. More information about when you can expect to receive a vaccination can be found on the Gov.UK website.

As Covid-19 vaccinations have been vigorously tested and shown to be safe and effective, the advice is to accept whichever one you are offered. However, if you suffer from severe allergies, it is best to consult with your GP before receiving the vaccine.

What to do once you have had the Covid-19 vaccination

The best protection for everybody right now is to continue to follow the current government guidelines of wearing a mask, handwashing, and social distancing. As more people are vaccinated experts can monitor the immunity and will update the guidance, as necessary.

If you've already had Covid-19 , do you need a vaccine?

People who have been ill with Covid-19 will still benefit from getting vaccinated due to the severe health risks associated with the illness.