Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

But researchers find an increased risk for unvaccinated people infected with SARS-CoV-2.

Covid and neurological disorders © SHUTTERSTOCK

Research, published in the BMJ, found no evidence that COVID-19 vaccines cause immune-mediated neurological disorders such as Bell's palsy (facial weakness), encephalomyelitis (inflammation of the brain and spinal cord), and Guillain-Barré syndrome (a nerve condition). But rates for these conditions were higher than otherwise expected for unvaccinated people infected with SARS-CoV-2.

The COVID-19 pandemic has caused more than 5.5 million deaths worldwide and rising. But a global research effort led to new vaccines being developed and approved, and to date over 9 billion doses have been administered worldwide.

As with all medicines the potential for adverse side effects exists, and recently concerns had been raised regarding cases of immune-mediated neurological disorders following vaccination.

Daniel Prieto-Alhambra, Professor of Pharmaco- and Device Epidemiology at NDORMS led an international team to look for any link. "Reports of Guillain-Barré Syndrome (GBS) cases following the use of some vaccines led to the EMA (European Medicines Agency) listing GBS as a very rare side effect. Cases of Bell's palsy, encephalomyelitis, and transverse myelitis have also been reported following vaccination so large-scale epidemiologic studies like ours are required to determine whether COVID-19 vaccination increases the risks above background rates in the general population."

The study used primary care records from the United Kingdom (UK) and primary care with linked hospital records from Spain to explore the potential link between COVID-19 vaccines and SARS-CoV-2 infection with the risk of developing either of the outcomes; Bell's palsy (facial weakness), encephalomyelitis (inflammation of the brain and spinal cord), Guillain-Barré syndrome (a nerve condition), and transverse myelitis (inflammation of the spinal cord).

Data from over 8 million recipients of the EMA approved Pfizer-BioNtech, Moderna, Oxford–AstraZeneca, Janssen, and Novavax vaccines were analysed. The incidence rates of each of the neurological outcomes in the vaccinated cohorts and SARS-CoV-2-infected cohorts were measured and compared with the "expected" rates of these conditions typically seen in the general population (based on data from more than 14 million people from between 2017 and 2019).

"We didn't see an association between the COVID-19 vaccines and the onset of the neurological conditions in the study." said Daniel. "However, we did observe an increased risk of Bell's Palsy, and encephalomyelitis in unvaccinated patients who had been infected with COVID-19. This underlines the safety of the vaccines being used against COVID-19 and the numerous ill-effects of being infected by SARS-CoV-2 for those people that remain unvaccinated."

Similar stories

Communication at the crossroads of the immune system

In his inaugural article in the Proceedings of the National Academy of Sciences as an NAS member (elected 2021), Prof Mike Dustin and his research team have explained how messages are passed across the immunological synapse. The research could have implications for future vaccine development and immunotherapy treatments.

Sara Khalid named Associate Professor at NDORMS

The University of Oxford has awarded the title of Associate Professor to Dr Sara Khalid as part of its recognition of excellence awards.

Max Stewart awarded an MRC fellowship

A DPhil candidate at NDORMS, Max received the MRC Clinical Research Training Fellowship to further his research into finding new treatments for peripheral nerve injuries.

The new Botnar strategy is announced

After a year as the Director of the Botnar Institute for Musculoskeletal Sciences, Professor Jonathan Rees announces a new structure and strategy that will further enhance research and treatment of bone, joint and musculoskeletal conditions.

New global health grant to improve outcomes for patients with hip fracture

Hip fracture patients in Low- and Middle-Income Countries (LMIC) in Asia are set to benefit from a new study that aims to bring best practice programmes to improve quality of life for patients and reduce healthcare costs.

NDORMS welcomes great-granddaughter of former Head of Department

Julia Strubell, great-granddaughter of Professor Josep Trueta, visited NDORMS to find out about his time here and to share her own work with staff and students.