Increased risk of sleep disorder in children who received swine flu vaccine
A study published in BMJ today finds an increased risk of narcolepsy in children and adolescents who received the A/H1N1 2009 influenza vaccine (Pandemrix) during the pandemic in England.
The results are consistent with previous studies from Finland and Sweden and indicate that the association is not confined to Scandinavian populations. However, the authors stress that the risk may still be overestimated, and they call for longer term monitoring of the cohort of children and adolescents exposed to Pandemrix to evaluate the exact level of risk.
In 2009, pandemic influenza A (H1N1) virus spread rapidly, resulting in millions of cases and over 18,000 deaths in over 200 countries. In England the vaccine Pandemrix was introduced in October 2009. By March 2010, around one in four (24%) of healthy children aged under 5 and just over a third (37%) aged 2-15 in a risk group had been vaccinated.
In August 2010 concerns were raised in Finland and Sweden about a possible association between narcolepsy and Pandemrix. And in 2012 a study from Finland reported a 13-fold increased risk in children and young people aged 4-19.
But a lack of reported cases in other countries led to speculation that any possible association might be restricted to these Scandinavian populations.
Narcolepsy is a chronic disorder of excessive daytime sleepiness, often accompanied by sudden muscle weakness triggered by strong emotion (known as cataplexy). To evaluate the risk after vaccination in England, a team of researchers reviewed case notes for 245 children and young people aged 4-18 from sleep centres and child neurology centres across England.
Of these, 75 had narcolepsy (56 with cataplexy) with onset after 1 January 2008. Eleven had been vaccinated before onset of symptoms; seven within six months.
After adjusting for clinical conditions, vaccination at any time was associated with a 14-fold increased risk of narcolepsy, whereas vaccination within six months before onset was associated with a 16-fold increased risk.
In absolute numbers, this means that one in 52,000 to 57,500 doses are associated with narcolepsy, say the authors.
They write: "The increased risk of narcolepsy after vaccination with ASO3 adjuvanted pandemic A/H1N1 2009 vaccine indicates a causal association, consistent with findings from Finland. Because of variable delay in diagnosis, however, the risk might be overestimated by more rapid referral of vaccinated children."
While further use of this vaccine for prevention of seasonal flu seems unlikely, they say their findings "have implications for the future licensure and use of AS03 adjuvanted pandemic vaccines containing different subtypes such H5 or H9."
And they conclude: "Further studies to assess the risk, if any, associated with the other A/H1N1 2009 vaccines used in the pandemic, including those with and without adjuvants, are also needed to inform the use of such vaccines in the event of a future pandemic."
More information: www.bmj.com/cgi/do… 136/bmj.f794
Journal reference: British Medical Journal (BMJ)
Provided by British Medical Journal
- Adjuvanted flu vaccine associated with child narcolepsy in Finland Mar 28, 2012 | not rated yet | 0
- Swine flu vaccine linked to child narcolepsy: EU watchdog Sep 21, 2012 | not rated yet | 0
- WHO confirms swine flu vaccine child narcolepsy concerns Feb 08, 2011 | not rated yet | 0
- Swine flu vaccine likely causes child narcolepsy: study Feb 01, 2011 | not rated yet | 0
- Swine flu vaccine linked to narcolepsy: Finnish study Sep 01, 2011 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
Classical and Quantum Mechanics via Lie algebras
Apr 15, 2011 I'd like to open a discussion thread for version 2 of the draft of my book ''Classical and Quantum Mechanics via Lie algebras'', available online at http://lanl.arxiv.org/abs/0810.1019 , and for the...
- More from Physics Forums - Independent Research
More news stories
(AP)—Government health officials are investigating several health problems reported with potentially contaminated medications made by a Tennessee specialty pharmacy.
Diseases, Conditions, Syndromes 4 hours ago | not rated yet | 0
(HealthDay)—Comorbid conditions often accompany alopecia areata, according to a study published online May 22 in JAMA Dermatology.
Diseases, Conditions, Syndromes 5 hours ago | not rated yet | 0
(HealthDay)—As a world-class golfer, Stacy Lewis' accomplishments are remarkable. But it was a physical challenge in her childhood that defined her ascent to the top of her sport.
Diseases, Conditions, Syndromes 5 hours ago | not rated yet | 0
Saudi Arabia said Friday it would send samples taken from animals possibly infected with a deadly SARS-like virus to the United States for testing in a bid to find the source of disease.
Diseases, Conditions, Syndromes 9 hours ago | not rated yet | 0
The World Health Organization voiced deep concern Thursday over the SARS-like virus that has killed 22 people in less than a year, saying it might potentially spread more widely between humans.
Diseases, Conditions, Syndromes 12 hours ago | 5 / 5 (1) | 0
Two mutations central to the development of infantile myofibromatosis (IM)—a disorder characterized by multiple tumors involving the skin, bone, and soft tissue—may provide new therapeutic targets, according to researchers ...
4 hours ago | 5 / 5 (1) | 0 |
(Medical Xpress)—A new study by researchers in the US has shown that an ancient virus can be modified to help in the fight against the simian immunodeficiency virus SIV, which is the equivalent in monkeys ...
9 hours ago | 5 / 5 (3) | 0 |
Talking on a hands-free device while behind the wheel can lead to a sharp increase in errors that could imperil other drivers on the road, according to new research from the University of Alberta.
3 hours ago | not rated yet | 0
Women at a particular stage in their monthly menstrual cycle may be more vulnerable to some of the psychological side-effects associated with stressful experiences, according to a study from UCL.
6 hours ago | 5 / 5 (1) | 0 |
Biological processes are generally based on events at the molecular and cellular level. To understand what happens in the course of infections, diseases or normal bodily functions, scientists would need to ...
7 hours ago | 5 / 5 (2) | 0 |
Kate O'Reilly's spring allergy survival kit includes the usual stuff - nasal sprays, allergy pills and a box of tissues. This season, she's added a new weapon to her line of defense: an app on her smartphone.
4 hours ago | not rated yet | 0