The Respiratory Syncytial Virus (RSV) is a major cause of severe respiratory infections, especially in infants, older adults, and immunocompromised individuals. To learn more about RSV and the importance of the vaccine, view the video below.
With the recent introduction of the RSV vaccine into immunisation programmes, concerns have recently emerged regarding rare side effects, particularly Guillain-Barré Syndrome (GBS).
In this blog, we’ll explore the prevalence of GBS following RSV vaccination and compare the risks posed by wild respiratory diseases versus vaccine-related side effects.
Understanding the Link Between RSV Vaccines and GBS
GBS is a rare condition where the body’s immune system mistakenly attacks peripheral nerves, causing muscle weakness and, in severe cases, paralysis. Often triggered by infection, although the cause is not always identified. In rare instances some vaccines have also been linked to a slightly increased risk of GBS, though the risk remains extremely low.
Visit the NHS website to learn more about GBS
Clinical trials and post-market surveillance of RSV vaccines have indicated that GBS may occur at a slightly higher rate in vaccinated individuals than in the general population. However, these occurrences are still exceptionally rare. Studies suggest that for every million people vaccinated, only a handful might develop GBS, making the risk exceedingly low compared to the benefits of preventing RSV-related complications.
How Common is GBS After RSV Vaccination?
In the first season of use in the US, over 12 million doses were given. Recent data suggests GBS was reported in around 10 cases for every million doses given in the first six weeks following administration.
To put this into perspective:
- This compares to a background rate of 11 cases per million of GBS following natural infection in those aged 75-79 years.
- The incident of GBS in the UK population is 2 cases per 100,000 people per year and increases with age.
- In the USA, the incidence is similar and between 3,000 and 6,000 people develop GBS each year.
- Most people recover fully from even the most severe cases of Guillain-Barré syndrome.
- The risk associated with natural infections, including flu and COVID-19, is significantly higher than that associated with vaccines.
- Studies have shown that people are much more likely to get GBS from viral infections like RSV and Influenza than the vaccine given to prevent the infection.
Comparing Risks: Wild Respiratory Diseases vs. Vaccine Side Effects
When evaluating any vaccine’s safety, it is crucial to weigh the risks of the disease against potential side effects. RSV can cause severe complications such as pneumonia, bronchiolitis, and hospitalisation, particularly among high-risk groups. The mortality and morbidity rates from RSV far exceed the extremely low risk of vaccine-related GBS.
For comparison:
- RSV leads to thousands of hospitalisations annually in infants and the elderly.
- Wild-type RSV infections have been linked to post-viral autoimmune complications, including GBS, at rates that likely surpass those seen with vaccination.
- Vaccines undergo rigorous safety monitoring, meaning that even extremely rare side effects like GBS are carefully tracked and studied.
Benefits of RSV Vaccination Outweigh the Risks
While concerns about GBS following RSV vaccination are valid, the absolute risk remains extremely low. The benefits of preventing severe RSV infections, hospitalisations, and complications far outweigh the potential for rare adverse effects. As research continues, healthcare professionals will closely monitor vaccine safety, ensuring that public health measures remain both effective and safe. Ongoing post marketing surveillance ensures vaccine safety.
For individuals at high risk of severe RSV complications, the vaccine presents a valuable tool in preventing illness and protecting vulnerable populations.
Useful resources:
UKHSA have provided guidance for Healthcare Professionals to support in the delivery of the RSV vaccination programme.
Please refer to the following resources on the GOV.UK Immunisation collection page – or click on the pictures below.
These guides offer insights into the protection offered by the RSV vaccine, its duration, potential side effects, and specific information on GBS occurrences.
You should also familiarise yourself with the guidance in The Green Book
There are publications available to provide to your patients and assist healthcare professionals and the public in making informed decisions – click on image
RSV – Older adults leaflet
RSV – Pregnant women leaflet
Useful posters to display in your workplace
RSV – Older adults Poster – click on picture
RSV – Pregnant women poster– click on picture
Useful Data – GBS Incidence Following RSV Infection:
Here’s a comparison of GBS incidence associated with RSV infection versus RSV vaccination:
Data Availability: Precise data on GBS incidence after RSV infection are limited. However, it’s recognized that RSV, like other viral infections, can trigger GBS in susceptible individuals. Such occurrences are considered uncommon.
GBS Incidence Following RSV Vaccination:
Recent evaluations have identified a slight increase in GBS cases following RSV vaccination:
- Pfizer’s Abrysvo Vaccine: Approximately 9 excess GBS cases per million doses administered.
- GSK’s Arexvy Vaccine: (not currently in use in the UK) Approximately 7 excess GBS cases per million doses administered (fda.gov).
Conclusion:
While both RSV infection and vaccination carry a minimal risk of GBS, the overall incidence remains very low in both scenarios. The benefits of RSV vaccination, particularly in preventing severe respiratory illness in high-risk populations, continue to outweigh these rare risks.
Healthcare professionals should remain vigilant for symptoms of GBS following RSV infection or vaccination, although such cases are rare. Prompt recognition and management are essential to ensure optimal patient outcomes. Practitioners should report any suspected adverse reactions through the online Yellow Card Scheme.