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BSI statement on the safety and effectiveness of mRNA COVID vaccines

As the professional body representing scientists and clinicians who study the immune system, the British Society for Immunology places the utmost value on an evidence-based approach to medical decisions. The following statement outlines our position on the safety and effectiveness of mRNA COVID-19 vaccines.

The safety and effectiveness assessments of all medicines and vaccines are based on robust and comprehensive analysis of the evidence.  These assessments are carried out as standard for all vaccines and medicines licenced in the UK. This approach is the gold standard of healthcare research and is the high-quality analysis the public deserve to allow them to make evidence-based decisions about their health.

The mRNA COVID-19 vaccines have been available for over two years and many millions of doses have been given to people in the UK and around the world.  Both in the initial clinical trials (before the vaccines were licenced) and throughout this rollout period, many researchers and health agencies have been carefully analysing the ongoing effectiveness and safety of these COVID-19 vaccines. In the UK, this includes the Medicines and Healthcare products Regulatory Agency (MHRA), the independent regulators of medicines who regularly publish reports on the safety of all vaccines, and the Joint Committee on Vaccination and Immunisation (JCVI) who are an independent expert group who advise UK Government on immunisations.  

There is a huge amount of evidence from multiple studies which shows that COVID-19 vaccines, including the mRNA vaccines, are the safest and most effective way to prevent serious illness and death from COVID-19, and the benefits by far outweigh the risks in the vast majority of people.  This is particularly true in vulnerable populations such as older people and those with conditions that weaken their immune system, who have been offered a booster vaccine this winter. We encourage all eligible people to get their booster COVID-19 vaccine when offered it to maximise the protection they have against falling seriously ill with COVID-19.


Links to further information from the British Society for Immunology

The British Society for Immunology has produced a number of resources to provide evidence-based and easy-to-understand information to the public about COVID-19 vaccines.  You can access all these resources for free via the links below.

Guide to vaccinations for COVID-19 - our comprehensive guide explains how COVID-19 vaccines work and answers your common questions as well as providing up-to-date information on the current approved COVID-19 vaccinations in the UK. 

COVID-19 vaccine infographics - we have produced a number of infographics on different aspects of COVID-19 vaccines to explain more about the science of how they work. Of particular interest may be our infographics on types of vaccine for COVID-19

UK COVID Vaccine Research Hub - an information hub, run by the BSI, to provide up-to-date information on UK research efforts on COVID vaccines. 

Vaccine resources in different languages - we have translated some of our resources on immunity, COVID-19 and vaccines into different languages, to be more accessible to diverse communities.


Links to further information from other organisations

NHS - their website has lots of information on COVID-19 vaccines

British Heart Foundation - they have an information page answering common questions around COVID-19 vaccines and heart health

MHRA Yellow Card reporting site - the MHRA is the independent regulator of vaccines. Their website has more information on how to report any side-effects from vaccination and a weekly report summarising information they have received via this scheme. 

World Health Organization - their website has lots of information on COVID-19 vaccines