10th January 2021
Given the causal link between the deployment of the Pandemrix swine flu vaccination in 2009/10 and the sudden onset of narcolepsy in some individuals, it is understandable that many in the narcolepsy community have questions about the ongoing vaccination campaign against the SARS-CoV-2 virus.
Since the outbreak of COVID-19, just over a year ago, Narcolepsy UK has been monitoring the situation closely and in early December, with the imminent availability of vaccines, our Chair specifically included the need for vigilance and understanding of our shared history with the British Sleep Society as part of a talk “Narcolepsy – The Patient Perspective”. We are confident that this message was received both positively and clearly, and given the number of sleep clinicians performing active roles in the treatment of COVID-19 patients in the UK and abroad, we are as satisfied as we can be that we are well placed to be informed of any issues that may affect you.
For those of you with additional conditions, the position is less clear and we ask you to continue to follow any specific individual advice you have received from your clinician. Specifically, we have raised our concerns about the lack of clear guidance to patients with neurological and/or autoimmune disorders with the Neurological Alliance via the National Neurosciences Advisory Group (NNAG). This point was raised by other represented patient groups and we will provide feedback to you as soon as we are able.
The benefits of vaccination as a public health measure are beyond question. Since vaccines were introduced, diseases such as smallpox and polio have been completely eradicated in the UK and others, including tetanus, measles and diphtheria have been drastically reduced. The World Health Organization estimates that vaccination prevents the death of some 3 million people worldwide every year and improvements in mass vaccination could save a further 1.5 million lives annually.
In the case of the H1N1 swine flu epidemic in 2009/10, vaccination with GlaxoSmithKline’s Pandemrix was followed by a significant increase in the incidence of narcolepsy. In the UK, it is estimated that this particular vaccine increased the risk of narcolepsy onset 14-fold in children and 4-fold in adults, a finding broadly mirrored in other countries that used Pandemrix. Subsequent research strongly suggests that it was the formulation of the H1N1 viral nucleoprotein used in Pandemrix (rather than the AS03 adjuvant) that likely triggered an autoimmune assault on hypocretin/orexin-producing cells in some individuals with a genetic vulnerability to developing narcolepsy.
The SARS-CoV-2 virus, the pathogen responsible for COVID-19, is a coronavirus and not an influenza virus. Most of the vaccines in development against SARS-CoV-2, including the three vaccines currently licensed for use in the UK, work by stimulating the immune system to produce antibodies specific to the CoV-2 spike protein. As the CoV-2 spike protein has a completely different structure to the H1N1 nucleoprotein used in the Pandemrix vaccine, there is no scientific reason why any of the COVID vaccines currently licensed (Pfizer, Oxford/AstraZeneca and Moderna) should trigger an autoimmune attack on the hypocretin/orexin-producing cells in the brain as occurred with Pandemrix.
As with all medicines and healthcare products, any adverse reactions to the COVID-19 vaccination should be logged through the MHRA’s Yellow Card Scheme.
Narcolepsy UK’s aim is always to empower you with information based on scientific evidence and we will continue to monitor the situation closely.
References
World Health Organization. Vaccines and immunization.
Miller, E. et al. (2013) Risk of narcolepsy in children and young people receiving AS03 adjuvanted pandemic A/H1N1 2009 influenza vaccine: retrospective analysis. BMJ 2013;346:f794
Stowe, J. et al. (2016) Risk of narcolepsy after AS03 adjuvanted pandemic A/H1N1 2009 influenza vaccine in adults: a case-coverage study in England. Sleep, Volume 39, Issue 5, May 2016, Pages 1051–1057 https://doi.org/10.5665/sleep.5752
Sarkanen, T. et al. (2018) Incidence of narcolepsy after H1N1 influenza and vaccinations: Systematic review and meta-analysis. Sleep Medicine Reviews 38: 177-186 https://doi.org/10.1016/j.smrv.2017.06.006
Vaarala et al. (2014) Antigenic differences between AS03-adjuvanted influenza A (H1N1) pandemic vaccines: implications for pandemrix-associated narcolepsy risk. PLoS ONE https://doi.org/10.1371/journal.pone.0114361
