Swine flu jab linked to sleep disorder: Fears one million children received jab that can increase risk of narcolepsy
Pandemrix was the main vaccine used in the UK during the swine flu pandemic three years ago
Almost a million children were given a swine flu jab which put them at increased risk of the sleep disorder narcolepsy, say scientists.
New research shows the Pandemrix vaccine carries a 14-fold extra risk of triggering narcolepsy, in which sufferers can fall asleep suddenly and unexpectedly.
For every 55,000 doses delivered, it is estimated around one child developed the condition.
Pandemrix was the main vaccine used in the UK during the swine flu pandemic three years ago.
It was given to six million people in high-risk groups, including children and those with conditions such as diabetes, heart disease and asthma.
At the height of the pandemic, between October 2009 and March 2010, more than 850,000 English children aged six months to 16 years were given the vaccine.
The jab was also given to 170,000 people, including children, when supplies of seasonal flu vaccine were in short supply between October 2010 and February 2011.
The latest research investigated the specific link with narcolepsy in children in England after reports of increased cases in Sweden and Finland.
It shows that children vaccinated here were also more likely to develop the disorder, although experts stressed Pandemrix has not been used for nearly two years and the period of highest risk was within a few months of getting a jab.
The research examined 75 children aged between four and 18 diagnosed with narcolepsy from January 2008 at sleep centres across England.
Researchers from the Health Protection Agency (HPA) and Papworth and Addenbrooke’s hospitals in Cambridge found 11 children had received the vaccine before their symptoms began.
They estimate the vaccine carries a 14-fold increased risk of narcolepsy, after adjusting for medical conditions, says a report published in the British Medical Journal.
This means one in 52,000 to 57,500 doses is linked with narcolepsy.
Researchers found 11 children had received the vaccine before their symptoms (posed by model)
Fears of an increased risk of the disorder led to restrictions on using the vaccine in people aged under 20 from 2011.
About 20,000 Britons suffer from narcolepsy, which causes ‘sleep attacks’ during the day and chronic tiredness.
There is no cure although symptoms can be controlled by drugs.
Lead author Professor Liz Miller, a consultant epidemiologist with the HPA, said the extra risk revealed in the study was consistent with findings from other European countries.
‘However, this risk may be overestimated by more rapid referral of vaccinated cases. Long term follow up of people exposed to Pandemrix is needed before we can fully establish the extent of the association’ she added.
Pandemrix contains an oil-in-water emulsion adjuvant - a substance added to increase the body’s immune response to that vaccine.
Prof Miller said the study had ‘implications for the future licensing and use of adjuvanted pandemic vaccines’.
Prof Adam Finn, professor of paediatrics at University of Bristol Medical School, said ‘As well as causing suffering and distress to those affected and their families, this raises some important questions about why exactly this happened with this particular vaccine.
‘The many children who received Pandemrix and are currently well are expected to remain fine as the problem, when it happens, seems to develop a few months after the vaccine and Pandemrix has not been in use for two years now.
‘Pandemrix is the only vaccine that has been linked to this problem - there is nothing to suggest that it occurs after other flu vaccines or vaccines against other diseases.’ Study co-author Dr John Shneerson, consultant physician from the Respiratory Support and Sleep Centre at Papworth Hospital in Cambridge, said ‘Narcolepsy is thought to be due to a loss of function of a small group of cells in one of the sleep centres in the brain, as a result of an abnormal reaction of the body’s immune system.
‘Pandemrix may have triggered an immune reaction against the sleep centre cells in those children who were genetically predisposed to develop narcolepsy.’ A Department of Health spokesman said ‘Pandemrix was developed specifically for use in a flu pandemic when the number of lives lost and serious cases could have been enormous.
‘The decision to recommend that children got this vaccine during the flu pandemic was based on evidence available at the time, along with the advice from the European Medicines Agency which approved its use.
‘We keep all emerging evidence under review and that’s why use of Pandemrix in those less than 20 years old was stopped in the UK in 2011.’
The comments below have not been moderated.
The views expressed in the contents above are those of our users and do not necessarily reflect the views of MailOnline.
We are no longer accepting comments on this article.