(Tue, 01 Feb 2011 11:09:00 +0000)
# 5274
As mentioned on Sunday, today the Finnish National Institute for Health and Welfare has released an interim report on what they now call a probable link between GSK’s Pandemrix vaccination, and an increase in narcolepsy in children and adolescents 4-19 years of age.
While citing a `a manifold increased risk of falling ill with narcolepsy during the 8 months following vaccination’, at this stage, the authors of this report state that this a `probable link’, and call it `Currently, the most likely explanation’.
Two major points.
- While the Pandemrix vaccine was taken by 31 million people across 47 countries, other than Finland, Sweden and Iceland, no other countries reported an increase in narcolepsy in 2010.
- Iceland, unlike Finland, reported an increase in narcolepsy among unvaccinated children during this same time period.
Both of which suggest that if there is a causal link between narcolepsy and the vaccine, there may be some other localized factors involved as well.
And over the next few months investigators will be looking at possible infectious agents, or other stimuli, that in conjunction with the vaccine might have conspired to raise the rates of narcolepsy in children aged 4-19.
We will await further details with interest, including any reports from Iceland and Sweden, the only other countries to report an increase in Narcolepsy in 2010.
Obviously, there is a lot here that investigators do not yet understand. And a final report is not expected until August 31st, 2011.
I’ve reproduced the official statement below, after which I’ll return with some comments.
1 Feb 2011
Among those 4-19 years of age who received Pandemrix®-vaccine had a manifold increased risk of falling ill with narcolepsy during the 8 months following vaccination in comparison to those unvaccinated in the same age group. Based on the evaluation done so far, the National Narcolepsy Task Force finds it probable that Pandemrix®-vaccination contributed to the observed increase in incidence of narcolepsy among those 4 -19 years of age. Currently, the most likely explanation is that the increase in narcolepsy is by joint effect of the vaccine and some other factor(s). At the moment, there is no evidence that the increase in narcolepsy observed in Finland could be attributed to the vaccine lots used. The results can be read in the Interim Report of the Task Force which is published on February 1st, 2011.
The association of Pandemrix-vaccination and narcolepsy was studied using extensive registry based data. Data gathered from hospital discharge registries on patients fallen ill with narcolepsy during years 2009-10 was linked with data from primary care records on pandemic vaccination. The observed association is so evident that it is unlikely that other so-called confounding factors could fully explain the phenomenon.
In Finland during years 2009–10, 60 children and adolescents aged 4-19 years fell ill with narcolepsy. These figures base on data from hospitals and primary care, and the review of individual patient records by a panel of neurologists and sleep researchers. Of those fallen ill, 52 (almost 90 percent) had received Pandemrix® vaccine, while the vaccine coverage in the entire age group was 70 percent. Based on the preliminary analyses, the risk of falling ill with narcolepsy among those vaccinated in the 4-19 years age group was 9-fold in comparison to those unvaccinated in the same age group. This increase was most pronounced among those 5–15 years of age. No cases were observed among those under 4 years of age. Also, no increase in cases of narcolepsy or signs of vaccination impacting risk of falling ill with narcolepsy was observed among those above 19 years of age.
In addition to Finland, increase in cases of narcolepsy observed only in Sweden and Iceland
In 2009, among countries using similar pandemic vaccine as was used in Finland, an increase in cases of narcolepsy has been observed only in Finland, Sweden and Iceland. Contrary to the observations in Finland, narcolepsy has occurred in greater numbers than expected also among unvaccinated children and teenagers in Iceland.
The association between narcolepsy and PandemrixR vaccine requires more investigations
During the coming months, these preliminary register based results will be confirmed in Finland. In further investigations, special attention will be given to infections and other stimuli in close time association with the pandemic vaccination. The significance of the possible joint effects will be explored.
In addition, other significant co-factors contributing to the onset of narcolepsy will be evaluated in epidemiologic, immunologic and genetic studies planned. The main aim of the immunologic studies is to clarify, whether the immunological responses to the different components of the Pandemrix® vaccine and to the A(H1N1) virus among those children and teenagers with genetic disposition to narcolepsy and those fallen ill with narcolepsy differ from the immunological responses of other children and teenagers not belonging to these risk groups.
It is also of utmost importance to find out whether the association is observed also elsewhere than in Finland. At present, Finland is participating in the ECDC contracted, VAESO led narcolepsy background incidence and case control studies which are being conducted in 9 European Union countries by pharmacovigilance researchers from Public Health Institutes, Regulatory Agencies and Universities. These studies will evaluate the contribution of the pandemic vaccines and other risk factors in the onset of narcolepsy, and confirm whether increase in incidence in narcolepsy is seen in other countries. The outcomes of these studies will be reported during early summer 2011.
By January 24, 2011, 56 notifications of narcolepsy in association with Pandemrix® vaccination have been received by the National Vaccine Adverse Events Register maintained at the National Institute of Health and Welfare in Finland. Of these, 54 cases belonged to the age group of 4–19 years. Among most of the notified cases, the onset of symptoms of narcolepsy had started approximately two months following Pandemrix® vaccination.
The final report from the National Narcolepsy Task Force will be released by 31st August 2011.
While I’m sure the anti-vaccination forces will try to use this latest report to condemn flu vaccines, it should be noted that this appears to be a localized phenomenon, and it may be the result of some unusual confluence of factors.
Despite their excellent safety record, vaccines have never been billed as 100% safe. When it comes to drugs, there simply is no such thing as a completely benign medication.
In clinical trials, even chemically inert placebos have produced adverse reactions.
Which is why one should always make a risk-benefit calculation when deciding to take any drug.
Vaccines can, and do, prevent serious – oft times life threatening – illness. Their downside is a very slight risk of experiencing adverse reactions.
Most are mild, but occasionally they can be serious.
If the Pandemrix vaccine is partially responsible for an increase in narcolepsy, then we need to understand why, so that it may be prevented in the future.
At the risk of sounding callous: a few dozen cases of narcolepsy – as tragic as that is for those dealing with it – does nothing to undo the immense good that vaccines have done around the globe.
Everything in life is a tradeoff.
Including the admittedly double-edged sword of modern medicine.
